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LitCovid-PD-HP

Id Subject Object Predicate Lexical cue hp_id
T1 26-34 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T2 287-295 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T3 932-940 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T4 962-970 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T5 1188-1194 Phenotype denotes asthma http://purl.obolibrary.org/obo/HP_0002099
T6 1289-1297 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T7 1329-1337 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T8 1457-1465 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T9 2224-2233 Phenotype denotes headaches http://purl.obolibrary.org/obo/HP_0002315
T10 2291-2299 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T11 2504-2513 Phenotype denotes headaches http://purl.obolibrary.org/obo/HP_0002315
T12 2613-2624 Phenotype denotes hypercapnia http://purl.obolibrary.org/obo/HP_0012416
T13 3259-3268 Phenotype denotes headaches http://purl.obolibrary.org/obo/HP_0002315
T14 4690-4697 Phenotype denotes itching http://purl.obolibrary.org/obo/HP_0000989
T15 4699-4706 Phenotype denotes fatigue http://purl.obolibrary.org/obo/HP_0012378
T16 4708-4715 Phenotype denotes anxiety http://purl.obolibrary.org/obo/HP_0000739
T17 4720-4734 Phenotype denotes claustrophobia http://purl.obolibrary.org/obo/HP_0025253
T18 4792-4800 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T19 4873-4881 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T20 4951-4962 Phenotype denotes hypercapnia http://purl.obolibrary.org/obo/HP_0012416
T21 5100-5108 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T22 5182-5190 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T23 6073-6081 Phenotype denotes Headache http://purl.obolibrary.org/obo/HP_0002315
T24 6148-6156 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T25 6170-6178 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T26 6262-6270 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T27 6308-6316 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T28 6318-6326 Phenotype denotes migraine http://purl.obolibrary.org/obo/HP_0002076
T29 6328-6352 Phenotype denotes tension type of headache http://purl.obolibrary.org/obo/HP_0012228
T30 6354-6370 Phenotype denotes cluster headache http://purl.obolibrary.org/obo/HP_0012199
T31 6412-6421 Phenotype denotes headaches http://purl.obolibrary.org/obo/HP_0002315
T32 6820-6828 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T33 6841-6849 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T34 7011-7019 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T35 7255-7263 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T36 7394-7402 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T37 9452-9460 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T38 11008-11015 Phenotype denotes allergy http://purl.obolibrary.org/obo/HP_0012393
T39 11029-11045 Phenotype denotes thyroid diseases http://purl.obolibrary.org/obo/HP_0000820
T40 11059-11066 Phenotype denotes anxiety http://purl.obolibrary.org/obo/HP_0000739
T41 11080-11099 Phenotype denotes high blood pressure http://purl.obolibrary.org/obo/HP_0000822
T42 11112-11118 Phenotype denotes asthma http://purl.obolibrary.org/obo/HP_0002099
T43 11307-11315 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T44 11384-11392 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T45 11394-11402 Phenotype denotes migraine http://purl.obolibrary.org/obo/HP_0002076
T46 11536-11544 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T47 11744-11761 Phenotype denotes sleep disturbance http://purl.obolibrary.org/obo/HP_0002360
T48 11786-11798 Phenotype denotes irritability http://purl.obolibrary.org/obo/HP_0000737
T49 11800-11811 Phenotype denotes photophobia http://purl.obolibrary.org/obo/HP_0000613
T50 11825-11843 Phenotype denotes nausea or vomiting http://purl.obolibrary.org/obo/HP_0002017
T51 12022-12030 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T52 12982-12990 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T53 13048-13055 Phenotype denotes Allergy http://purl.obolibrary.org/obo/HP_0012393
T54 13099-13105 Phenotype denotes Asthma http://purl.obolibrary.org/obo/HP_0002099
T55 13208-13220 Phenotype denotes hypertension http://purl.obolibrary.org/obo/HP_0000822
T56 13414-13429 Phenotype denotes Thyroid disease http://purl.obolibrary.org/obo/HP_0000820
T57 13473-13480 Phenotype denotes Anxiety http://purl.obolibrary.org/obo/HP_0000739
T58 13588-13605 Phenotype denotes Sleep disturbance http://purl.obolibrary.org/obo/HP_0002360
T59 13718-13730 Phenotype denotes Irritability http://purl.obolibrary.org/obo/HP_0000737
T60 13775-13786 Phenotype denotes Photophobia http://purl.obolibrary.org/obo/HP_0000613
T61 13891-13899 Phenotype denotes vomiting http://purl.obolibrary.org/obo/HP_0002013
T62 14082-14090 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T63 14134-14142 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T64 14211-14215 Phenotype denotes pain http://purl.obolibrary.org/obo/HP_0012531
T65 14491-14499 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T66 14703-14711 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T67 14789-14797 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T68 14819-14840 Phenotype denotes lack of concentration http://purl.obolibrary.org/obo/HP_0031987
T69 14946-14954 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T70 14984-14992 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T71 15052-15060 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T72 15087-15095 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T73 15119-15127 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T74 15171-15179 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T75 15244-15252 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T76 15308-15312 Phenotype denotes pain http://purl.obolibrary.org/obo/HP_0012531
T77 15736-15744 Phenotype denotes Headache http://purl.obolibrary.org/obo/HP_0002315
T78 16049-16057 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T79 16136-16145 Phenotype denotes headaches http://purl.obolibrary.org/obo/HP_0002315
T80 16368-16376 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T81 16503-16510 Phenotype denotes anxiety http://purl.obolibrary.org/obo/HP_0000739
T82 16514-16520 Phenotype denotes asthma http://purl.obolibrary.org/obo/HP_0002099
T83 16640-16648 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T84 16727-16735 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T85 17526-17532 Phenotype denotes Asthma http://purl.obolibrary.org/obo/HP_0002099
T86 17621-17628 Phenotype denotes Anxiety http://purl.obolibrary.org/obo/HP_0000739
T87 17866-17874 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T88 18095-18103 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T89 18429-18437 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T90 18499-18507 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T91 18684-18692 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T92 18862-18870 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T93 18892-18900 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T94 18974-18994 Phenotype denotes decrease in appetite http://purl.obolibrary.org/obo/HP_0004396
T95 19136-19144 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T96 19334-19343 Phenotype denotes tiredness http://purl.obolibrary.org/obo/HP_0012378
T97 20000-20008 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T98 20048-20056 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T99 20271-20279 Phenotype denotes Headache http://purl.obolibrary.org/obo/HP_0002315
T100 20331-20340 Phenotype denotes headaches http://purl.obolibrary.org/obo/HP_0002315
T101 20557-20565 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T102 20685-20693 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T103 20877-20884 Phenotype denotes hypoxia http://purl.obolibrary.org/obo/HP_0012418
T104 20886-20897 Phenotype denotes hypercapnia http://purl.obolibrary.org/obo/HP_0012416
T105 20954-20961 Phenotype denotes anxiety http://purl.obolibrary.org/obo/HP_0000739
T106 21321-21344 Phenotype denotes end-stage renal disease http://purl.obolibrary.org/obo/HP_0003774
T107 21689-21697 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T108 22726-22734 Phenotype denotes Headache http://purl.obolibrary.org/obo/HP_0002315
T109 22825-22834 Phenotype denotes headaches http://purl.obolibrary.org/obo/HP_0002315
T110 23020-23028 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T111 23223-23231 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T112 23278-23286 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T113 23343-23351 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T114 23821-23828 Phenotype denotes anxiety http://purl.obolibrary.org/obo/HP_0000739
T115 23877-23885 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T116 23976-23984 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T117 24420-24428 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T118 24527-24535 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T119 25200-25208 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T120 25560-25568 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T121 25743-25751 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T122 25808-25816 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T123 25848-25856 Phenotype denotes Headache http://purl.obolibrary.org/obo/HP_0002315
T124 25900-25904 Phenotype denotes pain http://purl.obolibrary.org/obo/HP_0012531
T125 25932-25940 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T126 25985-25993 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T127 26148-26156 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T128 26232-26255 Phenotype denotes endothelial dysfunction http://purl.obolibrary.org/obo/HP_0032654
T129 26433-26441 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T130 26572-26580 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T131 26740-26748 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T132 26789-26797 Phenotype denotes migraine http://purl.obolibrary.org/obo/HP_0002076
T133 26824-26832 Phenotype denotes Headache http://purl.obolibrary.org/obo/HP_0002315
T134 26899-26905 Phenotype denotes asthma http://purl.obolibrary.org/obo/HP_0002099
T135 27079-27087 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T136 27216-27224 Phenotype denotes rhinitis http://purl.obolibrary.org/obo/HP_0012384
T137 27226-27240 Phenotype denotes conjunctivitis http://purl.obolibrary.org/obo/HP_0000509
T138 27421-27429 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T139 27498-27505 Phenotype denotes hypoxia http://purl.obolibrary.org/obo/HP_0012418
T140 27555-27563 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T141 27672-27681 Phenotype denotes headaches http://purl.obolibrary.org/obo/HP_0002315
T142 27748-27756 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T143 27885-27893 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T144 28398-28407 Phenotype denotes headaches http://purl.obolibrary.org/obo/HP_0002315
T145 28743-28751 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T146 29133-29141 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T147 29263-29271 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T148 29446-29454 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T149 29464-29475 Phenotype denotes dehydration http://purl.obolibrary.org/obo/HP_0001944
T150 29669-29677 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T151 29808-29816 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315
T152 29882-29890 Phenotype denotes headache http://purl.obolibrary.org/obo/HP_0002315

LitCovid-PubTator

Id Subject Object Predicate Lexical cue tao:has_database_id
2 26-34 Disease denotes headache MESH:D006261
3 68-76 Disease denotes COVID-19 MESH:C000657245
8 134-149 Species denotes new coronavirus Tax:2697049
9 151-159 Disease denotes COVID-19 MESH:C000657245
10 287-295 Disease denotes headache MESH:D006261
11 374-385 Disease denotes cephalalgia MESH:D006261
13 588-596 Disease denotes COVID-19 MESH:C000657245
21 681-684 Gene denotes age Gene:5973
22 650-655 Species denotes women Tax:9606
23 932-940 Disease denotes headache MESH:D006261
24 962-970 Disease denotes headache MESH:D006261
25 1188-1194 Disease denotes asthma MESH:D001249
26 1289-1297 Disease denotes headache MESH:D006261
27 1329-1337 Disease denotes headache MESH:D006261
29 1457-1465 Disease denotes headache MESH:D006261
31 1709-1717 Disease denotes COVID-19 MESH:C000657245
33 2007-2013 Disease denotes coughs MESH:D003371
35 2224-2233 Disease denotes headaches MESH:D006261
37 2291-2299 Disease denotes headache MESH:D006261
40 2504-2513 Disease denotes headaches MESH:D006261
41 2601-2624 Disease denotes hypoxaemia, hypercapnia MESH:D006935
43 3259-3268 Disease denotes headaches MESH:D006261
50 3304-3319 Species denotes new coronavirus Tax:2697049
51 3321-3331 Species denotes SARS-CoV-2 Tax:2697049
52 3677-3685 Species denotes patients Tax:9606
53 3461-3469 Disease denotes COVID-19 MESH:C000657245
54 3622-3628 Disease denotes deaths MESH:D003643
55 3759-3765 Disease denotes deaths MESH:D003643
58 3819-3827 Disease denotes COVID-19 MESH:C000657245
59 4383-4391 Disease denotes COVID-19 MESH:C000657245
70 4585-4611 Disease denotes decreased visual, auditory MESH:D014786
71 4690-4697 Disease denotes itching MESH:D011537
72 4699-4706 Disease denotes fatigue MESH:D005221
73 4708-4715 Disease denotes anxiety MESH:D001007
74 4720-4734 Disease denotes claustrophobia MESH:D010698
75 4792-4800 Disease denotes headache MESH:D006261
76 4873-4881 Disease denotes headache MESH:D006261
77 4936-4962 Disease denotes hypoxaemia and hypercapnia MESH:D006935
78 5100-5108 Disease denotes headache MESH:D006261
79 5182-5190 Disease denotes headache MESH:D006261
82 5396-5404 Species denotes patients Tax:9606
83 5322-5330 Disease denotes COVID-19 MESH:C000657245
85 5583-5593 Species denotes outpatient Tax:9606
87 5929-5937 Disease denotes COVID-19 MESH:C000657245
98 6073-6091 Disease denotes Headache Disorders MESH:D020773
99 6108-6112 Disease denotes ICHD
100 6148-6156 Disease denotes headache MESH:D006261
101 6170-6178 Disease denotes headache MESH:D006261
102 6262-6270 Disease denotes headache MESH:D006261
103 6308-6316 Disease denotes headache MESH:D006261
104 6318-6326 Disease denotes migraine MESH:D008881
105 6344-6352 Disease denotes headache MESH:D006261
106 6354-6370 Disease denotes cluster headache MESH:D003027
107 6412-6421 Disease denotes headaches MESH:D006261
114 6529-6549 Disease denotes SARS-CoV-2 infection MESH:C000657245
115 6820-6828 Disease denotes headache MESH:D006261
116 6841-6849 Disease denotes headache MESH:D006261
117 7011-7019 Disease denotes headache MESH:D006261
118 7255-7263 Disease denotes headache MESH:D006261
119 7394-7402 Disease denotes headache MESH:D006261
121 9452-9460 Disease denotes headache MESH:D006261
127 10130-10133 Gene denotes age Gene:5973
128 10079-10082 Species denotes men Tax:9606
129 10099-10104 Species denotes women Tax:9606
130 10192-10204 Species denotes participants Tax:9606
131 10867-10887 Disease denotes SARS-CoV-2 infection MESH:C000657245
139 11212-11219 Species denotes tobacco Tax:4097
140 11008-11015 Disease denotes allergy MESH:D004342
141 11029-11045 Disease denotes thyroid diseases MESH:D013959
142 11059-11066 Disease denotes anxiety MESH:D001007
143 11112-11118 Disease denotes asthma MESH:D001249
144 11131-11144 Disease denotes dyslipidaemia
145 11160-11168 Disease denotes diabetes MESH:D003920
151 11244-11251 Species denotes persons Tax:9606
152 11307-11315 Disease denotes headache MESH:D006261
153 11384-11392 Disease denotes headache MESH:D006261
154 11394-11402 Disease denotes migraine MESH:D008881
155 11536-11544 Disease denotes headache MESH:D006261
161 11744-11761 Disease denotes sleep disturbance MESH:D012893
162 11786-11798 Disease denotes irritability MESH:D001523
163 11800-11811 Disease denotes photophobia MESH:D020795
164 11825-11831 Disease denotes nausea MESH:D009325
165 11835-11843 Disease denotes vomiting MESH:D014839
180 12073-12076 Gene denotes Age Gene:5973
181 13148-13155 Species denotes Tobacco Tax:4097
182 12022-12030 Disease denotes headache MESH:D006261
183 12920-12928 Disease denotes COVID-19 MESH:C000657245
184 12982-12990 Disease denotes headache MESH:D006261
185 13099-13105 Disease denotes Asthma MESH:D001249
186 13208-13220 Disease denotes hypertension MESH:D006973
187 13262-13273 Disease denotes Cardiopathy MESH:C536187
188 13312-13329 Disease denotes Dyslipidaemia 14 OMIM:615513
189 13366-13374 Disease denotes Diabetes MESH:D003920
190 13414-13429 Disease denotes Thyroid disease MESH:D013959
191 13473-13480 Disease denotes Anxiety MESH:D001007
192 13712-13730 Disease denotes 0001  Irritability MESH:D001523
193 13882-13899 Disease denotes Sickness/vomiting MESH:D014839
202 14054-14066 Species denotes participants Tax:9606
203 14082-14090 Disease denotes headache MESH:D006261
204 14134-14142 Disease denotes headache MESH:D006261
205 14211-14215 Disease denotes pain MESH:D010146
206 14491-14499 Disease denotes headache MESH:D006261
207 14703-14711 Disease denotes headache MESH:D006261
208 14789-14797 Disease denotes headache MESH:D006261
209 14946-14954 Disease denotes headache MESH:D006261
211 14984-14992 Disease denotes headache MESH:D006261
219 15052-15060 Disease denotes headache MESH:D006261
220 15087-15095 Disease denotes headache MESH:D006261
221 15119-15130 Disease denotes headache P MESH:D006261
222 15171-15179 Disease denotes headache MESH:D006261
223 15244-15252 Disease denotes headache MESH:D006261
224 15308-15312 Disease denotes pain MESH:D010146
225 15736-15744 Disease denotes Headache MESH:D006261
228 16049-16057 Disease denotes headache MESH:D006261
229 16136-16145 Disease denotes headaches MESH:D006261
237 16382-16385 Gene denotes age Gene:5973
238 16474-16481 Species denotes tobacco Tax:4097
239 16368-16376 Disease denotes headache MESH:D006261
240 16503-16510 Disease denotes anxiety MESH:D001007
241 16514-16520 Disease denotes asthma MESH:D001249
242 16640-16648 Disease denotes headache MESH:D006261
243 16727-16735 Disease denotes headache MESH:D006261
247 17586-17593 Species denotes Tobacco Tax:4097
248 17526-17532 Disease denotes Asthma MESH:D001249
249 17621-17628 Disease denotes Anxiety MESH:D001007
251 17866-17874 Disease denotes headache MESH:D006261
254 18095-18103 Disease denotes headache MESH:D006261
255 18429-18437 Disease denotes headache MESH:D006261
258 18499-18507 Disease denotes headache MESH:D006261
259 18684-18692 Disease denotes headache MESH:D006261
266 18830-18833 Chemical denotes PPQ
267 18862-18870 Disease denotes headache MESH:D006261
268 18892-18900 Disease denotes headache MESH:D006261
269 19087-19106 Disease denotes occupational stress MESH:D000073397
270 19136-19144 Disease denotes headache MESH:D006261
271 19334-19343 Disease denotes tiredness MESH:D005221
275 19840-19850 Species denotes SARS-CoV-2 Tax:2697049
276 19500-19508 Disease denotes COVID-19 MESH:C000657245
277 20000-20008 Disease denotes headache MESH:D006261
287 20048-20056 Disease denotes headache MESH:D006261
288 20271-20279 Disease denotes Headache MESH:D006261
289 20321-20340 Disease denotes secondary headaches MESH:D051271
290 20557-20565 Disease denotes headache MESH:D006261
291 20685-20693 Disease denotes headache MESH:D006261
292 20714-20737 Disease denotes multifactorial disorder MESH:D004194
293 20877-20884 Disease denotes hypoxia MESH:D000860
294 20886-20897 Disease denotes hypercapnia MESH:D006935
295 20954-20961 Disease denotes anxiety MESH:D001007
313 21307-21315 Species denotes patients Tax:9606
314 21115-21125 Chemical denotes oxygen and
315 21129-21143 Chemical denotes carbon dioxide MESH:D002245
316 21145-21148 Chemical denotes CO2 MESH:D002245
317 21447-21453 Chemical denotes oxygen MESH:D010100
318 21605-21608 Chemical denotes CO2 MESH:D002245
319 21850-21853 Chemical denotes CO2 MESH:D002245
320 21942-21945 Chemical denotes CO2 MESH:D002245
321 22901-22907 Chemical denotes oxygen MESH:D010100
322 22912-22915 Chemical denotes CO2 MESH:D002245
323 21321-21344 Disease denotes end-stage renal disease MESH:D007676
324 21689-21697 Disease denotes headache MESH:D006261
325 21735-21755 Disease denotes respiratory symptoms MESH:D012818
326 22726-22734 Disease denotes Headache MESH:D006261
327 22798-22802 Disease denotes ICHD
328 22825-22834 Disease denotes headaches MESH:D006261
329 22842-22863 Disease denotes homeostatic disorders MESH:D030342
336 23020-23028 Disease denotes headache MESH:D006261
337 23223-23231 Disease denotes headache MESH:D006261
338 23278-23286 Disease denotes headache MESH:D006261
339 23317-23321 Disease denotes ICHD
340 23343-23351 Disease denotes headache MESH:D006261
341 23566-23576 Disease denotes irritative MESH:D001523
351 24007-24017 Species denotes SARS-CoV-2 Tax:2697049
352 24137-24143 Species denotes people Tax:9606
353 24479-24482 Chemical denotes PPQ
354 23821-23828 Disease denotes anxiety MESH:D001007
355 23877-23885 Disease denotes headache MESH:D006261
356 23976-23984 Disease denotes headache MESH:D006261
357 24175-24180 Disease denotes death MESH:D003643
358 24190-24196 Disease denotes injury MESH:D014947
359 24420-24428 Disease denotes headache MESH:D006261
362 24527-24535 Disease denotes headache MESH:D006261
363 25200-25208 Disease denotes headache MESH:D006261
378 25755-25758 Gene denotes Age Gene:5973
379 26009-26012 Gene denotes age Gene:5973
380 25638-25641 Gene denotes age Gene:5973
381 26454-26461 Species denotes tobacco Tax:4097
382 25560-25568 Disease denotes headache MESH:D006261
383 25743-25751 Disease denotes headache MESH:D006261
384 25808-25816 Disease denotes headache MESH:D006261
385 25848-25856 Disease denotes Headache MESH:D006261
386 25900-25904 Disease denotes pain MESH:D010146
387 25932-25951 Disease denotes headache disability MESH:D006261
388 25985-25993 Disease denotes headache MESH:D006261
389 26148-26156 Disease denotes headache MESH:D006261
390 26223-26255 Disease denotes vascular endothelial dysfunction MESH:D057772
391 26433-26441 Disease denotes headache MESH:D006261
408 26705-26712 Species denotes tobacco Tax:4097
409 26775-26783 Species denotes patients Tax:9606
410 26875-26883 Species denotes patients Tax:9606
411 26979-26987 Species denotes patients Tax:9606
412 27182-27189 Chemical denotes steroid MESH:D013256
413 26572-26580 Disease denotes headache MESH:D006261
414 26740-26748 Disease denotes headache MESH:D006261
415 26789-26797 Disease denotes migraine MESH:D008881
416 26824-26832 Disease denotes Headache MESH:D006261
417 26899-26905 Disease denotes asthma MESH:D001249
418 27079-27087 Disease denotes headache MESH:D006261
419 27216-27224 Disease denotes rhinitis MESH:D012220
420 27226-27240 Disease denotes conjunctivitis MESH:D003231
421 27421-27429 Disease denotes headache MESH:D006261
422 27498-27505 Disease denotes hypoxia MESH:D000860
423 27555-27563 Disease denotes headache MESH:D006261
431 28557-28563 Species denotes people Tax:9606
432 28141-28144 Chemical denotes CO2 MESH:D002245
433 27672-27681 Disease denotes headaches MESH:D006261
434 27748-27756 Disease denotes headache MESH:D006261
435 27885-27893 Disease denotes headache MESH:D006261
436 28398-28407 Disease denotes headaches MESH:D006261
437 28743-28751 Disease denotes headache MESH:D006261
442 29133-29141 Disease denotes headache MESH:D006261
443 29263-29271 Disease denotes headache MESH:D006261
444 29446-29454 Disease denotes headache MESH:D006261
445 29464-29475 Disease denotes dehydration MESH:D003681
449 29669-29677 Disease denotes headache MESH:D006261
450 29808-29816 Disease denotes headache MESH:D006261
451 29882-29890 Disease denotes headache MESH:D006261
453 31003-31006 Gene denotes ABC Gene:10058
455 31261-31268 Species denotes Patient Tax:9606

LitCovid-sentences

Id Subject Object Predicate Lexical cue
T1 0-85 Sentence denotes Mask-associated ‘de novo’ headache in healthcare workers during the COVID-19 pandemic
T2 87-95 Sentence denotes Abstract
T3 96-106 Sentence denotes Objectives
T4 107-213 Sentence denotes The pandemic caused by the new coronavirus (COVID-19) has changed care activities of health professionals.
T5 214-410 Sentence denotes We analysed the possible association between the appearance of ‘de novo’ headache according to the type of mask used, the related factors and the impact of the cephalalgia on health professionals.
T6 412-419 Sentence denotes Methods
T7 420-487 Sentence denotes Cross-sectional study in a tertiary hospital in Extremadura, Spain.
T8 488-612 Sentence denotes We provided an online questionnaire to healthcare workers during the period of maximum incidence of COVID-19 in our setting.
T9 614-621 Sentence denotes Results
T10 622-711 Sentence denotes The subjects are n=306, 244 women (79.7%), with an average age of 43 years (range 23–65).
T11 712-810 Sentence denotes Of the total, 129 (42.2%) were physicians, 112 (36.6%) nurses and 65 (21.2%) other health workers.
T12 811-876 Sentence denotes 208 (79.7%) used surgical masks and 53 (20.3%) used filter masks.
T13 877-941 Sentence denotes Of all those surveyed, 158 (51.6%) presented ‘de novo’ headache.
T14 942-1226 Sentence denotes The occurrence of a headache was independently associated with the use of a filter mask, OR 2.14 (95% CI 1.07 to 4.32); being a nurse, OR 2.09 (95% CI 1.18 to 3.72) or another health worker, OR 6.94 (95% CI 3.01 to 16.04); or having a history of asthma, OR 0.29 (95% CI 0.09 to 0.89).
T15 1227-1416 Sentence denotes According to the type of mask used, there were differences in headache intensity, and the impact of a headache in the subjects who used a filter mask was worse in all the aspects evaluated.
T16 1418-1428 Sentence denotes Conclusion
T17 1429-1628 Sentence denotes The appearance of ‘de novo’ headache is associated with the use of filter masks and is more frequent in certain healthcare workers, causing a greater occupational, family, personal and social impact.
T18 1630-1642 Sentence denotes Key messages
T19 1644-1685 Sentence denotes What is already known about this subject?
T20 1686-1837 Sentence denotes During the increase in COVID-19 cases, health authorities established the mandatory use of Personal Protective Equipment (PPE) by health professionals.
T21 1838-2051 Sentence denotes Face masks are recommended as a simple barrier to help prevent respiratory droplets from travelling through the air and reaching others when the person wearing the mask coughs, sneezes, speaks or raises his voice.
T22 2052-2110 Sentence denotes In ‘front-line’ work, wearing masks can be time consuming.
T23 2111-2234 Sentence denotes Although highly effective masks are generally well tolerated, some health problems have been reported, including headaches.
T24 2236-2262 Sentence denotes What are the new findings?
T25 2263-2458 Sentence denotes The appearance of ‘de novo’ headache is associated with the use of filter masks and is more frequent in certain health workers, causing a greater occupational, family, personal and social impact.
T26 2459-2635 Sentence denotes The pathogenesis of ‘de novo’ PPE-associated headaches could possibly have several aetiological considerations, including mechanical factors, hypoxaemia, hypercapnia or stress.
T27 2637-2716 Sentence denotes How might this impact on policy or clinical practice in the foreseeable future?
T28 2717-2978 Sentence denotes Given that the use of these devices will tend to become widespread due to the implications of the pandemic, we believe it is important to promote prevention and protection strategies that guarantee the safety of workers, without affecting their quality of life.
T29 2979-3096 Sentence denotes Better strategies may be needed to design various types of PPE and reduce their exposure time for healthcare workers.
T30 3097-3269 Sentence denotes Through engineered solutions, the next-generation protective mask will have an improved design with an emphasis on tolerability and consequently be less prone to headaches.
T31 3271-3283 Sentence denotes Introduction
T32 3284-3382 Sentence denotes In December 2019, a new coronavirus, SARS-CoV-2, started an outbreak in the Chinese city of Wuhan.
T33 3383-3786 Sentence denotes In January 2020 its clinical picture was defined as a disease associated with COVID-19.1 2 This outbreak evolved into a pandemic and on 24 May 2020, 216 countries had been affected, 5 206 614 cases had been confirmed worldwide and 337 736 deaths.3 In Spain, there are 233 037 cases, and 27 940 patients have lost their lives.4 In the region of Extremadura, 3047 cases and 506 deaths have been reported.5
T34 3787-3964 Sentence denotes During the increase in cases of COVID-19 in our environment, the health authorities established the mandatory use of Personal Protective Equipment (PPE) by health professionals.
T35 3965-4063 Sentence denotes This PPE consists of a protective suit, surgical gloves, protective goggles, shield and face mask.
T36 4064-4393 Sentence denotes In the case of face masks, they must be highly effective, with type FFP2 (filtering face pieces) (in Europe), N95 (USA) and KN95 (China) recommended.6 There are other types of masks (surgical masks or FPP1 among others), of lesser effectiveness, which are used by healthcare personnel who is not in direct contact with COVID-19.7
T37 4394-5215 Sentence denotes In ‘front-line’ work, the use of masks can be very prolonged.8 Although, in general, highly effective masks are well tolerated, some problems have been reported, such as: general discomfort; decreased visual, auditory or vocal capacity; excessive heat or humidity; facial pressure; skin lesions; itching; fatigue; anxiety and claustrophobia.9 Another effect described in the 2003 SARS epidemic was headache, whose prevalence reached 37.3% of the health personnel studied.10 This headache can be related to mechanical factors, the presence of hypoxaemia and hypercapnia or to the stress associated with mask use.11 12 Our aim is to demonstrate if there is an association between the appearance of ‘de novo’ headache with the type of mask and its time of use, as well as the impact of this headache on health professionals.
T38 5217-5223 Sentence denotes Method
T39 5224-5405 Sentence denotes The study was conducted in the health area of a tertiary hospital, where our health system in the COVID-19 period urged health professionals to use PPE during contact with patients.
T40 5406-5602 Sentence denotes These protective systems were mandatory among health workers, both in high-risk areas, and in general medical wards, central hospital radiology, and diagnostic imaging areas or outpatient clinics.
T41 5603-5714 Sentence denotes This involved the use of different types of more or less tight-fitting masks, and sometimes glasses or screens.
T42 5715-5876 Sentence denotes Using a self-administered questionnaire addressed to health workers in our health area, we carried out a cross-sectional study during the first week of May 2020.
T43 5877-6026 Sentence denotes In the previous month, the number of admissions for COVID-19 was very high and attendance protocols required the use of these devices by all workers.
T44 6027-6424 Sentence denotes Following the International Classification of Headache Disorders, Third Edition (ICHD-3) criteria,11 we define ‘de novo’ headache: ‘when a new headache occurs for the first time in close temporal relationship to use PPE, even when the headache has the characteristics of a primary headache (migraine, tension type of headache, cluster headache or one of the other trigeminal autonomic headaches)’.
T45 6425-7573 Sentence denotes The questionnaire collected the following information: (1) demographics; (2) medical history, including SARS-CoV-2 infection; (3) type and pattern of mask use: surgical masks versus self-filter masks of particles and liquid aerosols (FFP), average number of hours of use per day and use of other protective devices (glasses or screens); (4) frequency and characteristics of pre-existing primary headache (changes in headache frequency, attack duration and frequency, as well as drug use and response); (5) the main variable of the study was personal opinion about the presence of a new headache in the period in which these protective systems were mandatory; (6) presence of other symptoms potentially associated with the use of facial protection equipment; (7) we evaluated the self-perceived impact of the presence of new-onset headache using the Likert scale on social, occupational, family and personal aspects; (8) we also evaluated the self-perceived impact that headache conditions have on the performance of work activities and (9) lastly, we analysed self-perceived work stress by means of the Psychosomatic Problems Questionnaire (PPQ).13
T46 7574-7700 Sentence denotes The questionnaire was written after an analysis of the literature and a thorough reflection on the problem to be investigated.
T47 7701-7852 Sentence denotes It included a request for voluntary collaboration, information on the reason for the survey, instructions for completing the questionnaire and consent.
T48 7853-7905 Sentence denotes The average time taken to complete was about 20 min.
T49 7906-7972 Sentence denotes The information collection procedure chosen was the online survey.
T50 7973-8130 Sentence denotes The survey was scheduled to be conducted over 5 consecutive days, between 1 May 2020 and 6 May 2020, with the data collected referring to the previous month.
T51 8131-8285 Sentence denotes The data collected in the study respects the anonymity of the subject and there is no possibility of access to any personal information of the individual.
T52 8286-8446 Sentence denotes The data analysed are restricted to the study investigators, health authorities and the Ethics Committee, when required, in accordance with current legislation.
T53 8448-8468 Sentence denotes Statistical analysis
T54 8469-8616 Sentence denotes Prior to the analysis of relationships between variables, descriptive analyses of the different areas that make up the study have been carried out.
T55 8617-8790 Sentence denotes These descriptive analyses include percentage distributions of the different categories of the analysed variables and, in the case of quantitative variables, average and SD.
T56 8791-9113 Sentence denotes These same analyses, shown as a cross between variables by means of contingency tables or comparison of averages, have also been elaborated as a preamble to the statistical tests that have been carried out to corroborate if there is a relationship between different variables, thus showing the hypotheses to be contrasted.
T57 9114-9221 Sentence denotes Depending on the nature of the variable and the distribution of the sample, different tests have been used.
T58 9222-9373 Sentence denotes We used the Χ2 test to contrast whether there is independence between two categorical variables using a contingency table when the data are not paired.
T59 9374-9655 Sentence denotes For the analysis of the predictive factors with the appearance of a ‘de novo’ headache, we used binary logistic regression methods by steps backwards, to maximise sensitivity; variables with a univariate association of p<0.200 were included as candidates in the multivariate model.
T60 9656-9875 Sentence denotes To measure the relationship between the different variables in the study, statistical tests with a 95% significance level were used as an acceptance threshold for the hypotheses to be tested, that is, a p value of 0.05.
T61 9876-9978 Sentence denotes All statistical analyses were performed using the SPSS V.25.0 statistical package program for Windows.
T62 9980-9987 Sentence denotes Results
T63 9988-10150 Sentence denotes A total of 306 health professionals and other health workers participated in the study, 62 men (20.3%) and 244 women (79.7%), with an average age of 43 years (SD:
T64 10151-10161 Sentence denotes 11; range:
T65 10162-10169 Sentence denotes 23–65).
T66 10170-10343 Sentence denotes Of these, 129 (42.2%) participants were physicians, 112 (36.6%) nurses and the rest, 65 (21.2%) other health workers (assistants, guards, technicians, administrative staff).
T67 10344-10510 Sentence denotes With regard to the work shift, 89 (34.1%) worked in the morning and on duty, 91 (34.9%) at morning, afternoon and night shifts, and 81 (31.0%) in morning shifts only.
T68 10511-10682 Sentence denotes The surgical mask was used by 208 (79.7%) of those surveyed, and the filter mask (FFP2 or KN95) was used by 53 (20.3%), with no difference in the mean time of use 7.0 (SD:
T69 10683-10705 Sentence denotes 2.3) hours vs 6.7 (SD:
T70 10706-10726 Sentence denotes 2.5) hours, p=0.289.
T71 10727-10844 Sentence denotes A total of 46.4% (121) reported not habitually using other facial protection devices such as glasses, screens or PPE.
T72 10845-10921 Sentence denotes The rate of confirmed SARS-CoV-2 infection in the study population was 4.6%.
T73 10922-11179 Sentence denotes The most frequently reported diseases in the total sample in order of frequency were: allergy, 34 (13.0%); thyroid diseases, 28 (10.7%); anxiety, 26 (10.0%); high blood pressure, 18 (6.9%); asthma, 17 (6.5%); dyslipidaemia, 14 (5.4%) and diabetes, 2 (0.8%).
T74 11180-11232 Sentence denotes A total of 15.7% (41) indicated tobacco consumption.
T75 11233-11403 Sentence denotes Of the 306 persons surveyed, 158 (51.6%) reported the appearance of a new headache during the period of study, of whom 65 (41.1%) had previously had a headache (migraine:
T76 11404-11424 Sentence denotes 27 (17.1%), tension:
T77 11425-11447 Sentence denotes 26 (16.5%) and others:
T78 11448-11459 Sentence denotes 11 (6.9%)).
T79 11460-11545 Sentence denotes There were 103 (33.7%) subjects who did not observe the appearance of a new headache.
T80 11546-11677 Sentence denotes A 14.7% were undecided on the answer ‘I don't know’ or the answer was ‘maybe’; these 45 subjects were eliminated from the analysis.
T81 11678-11844 Sentence denotes They were also asked about the presence of other symptoms such as sleep disturbance, loss of concentration, irritability, photophobia, sonophobia, nausea or vomiting.
T82 11845-11897 Sentence denotes Table 1 shows the characteristics of the population.
T83 11898-12006 Sentence denotes Table 1 Baseline conditions and mask and Personal Protective Equipment (PPE) usage among healthcare workers
T84 12007-12039 Sentence denotes Total De novo headache P value
T85 12040-12047 Sentence denotes No Yes
T86 12048-12072 Sentence denotes N= 261 (n=103) (n=158)
T87 12073-12134 Sentence denotes Age, years (SD) 42.9 (10.7) 40.8 (11.4) 44.4 (10.1) 0.009
T88 12135-12193 Sentence denotes Female gender 208 (79.7%) 73 (31.1%) 135 (64.9%) 0.004
T89 12194-12214 Sentence denotes Occupation 0.0001
T90 12215-12258 Sentence denotes  Doctor 112 (42.9%) 61(54.5%) 51 (45.5%)
T91 12259-12300 Sentence denotes  Nurse 95 (36.4%) 33 (34.7%) 62(65.3%)
T92 12301-12341 Sentence denotes  Others 54 (20.7%) 9(16.7%) 45(83.3%)
T93 12342-12363 Sentence denotes Work shift <0.0001
T94 12364-12428 Sentence denotes  Mornings and 24-hour duties 89 (34.1%) 51 (57.3%) 38 (42.7%)
T95 12429-12481 Sentence denotes  Rotating shifts 91 (34.9%) 26 (28.6%) 65 (71.4%)
T96 12482-12525 Sentence denotes  Others 81 (31.0%) 26 (32.1%) 55 (67.9%)
T97 12526-12552 Sentence denotes Type of face mask 0.029
T98 12553-12605 Sentence denotes  Surgical mask 208 (79.7%) 89 (42.8%) 119 (57.2%)
T99 12606-12651 Sentence denotes  N95/FFP2 53 (20.3%) 14 (26.4%) 39 (73.6%)
T100 12652-12725 Sentence denotes Number of hours worn per day (SD) 6.9 (2.3) 6.8 (2.4) 7.0 (2.2) 0.474
T101 12726-12745 Sentence denotes Use of another PPE:
T102 12749-12754 Sentence denotes 0.203
T103 12755-12803 Sentence denotes  Face shield 54 (20.7%) 21 (38.9%) 33 (61.1%)
T104 12804-12859 Sentence denotes  Protective eyewear 33 (12.6%) 13 (39.4%) 20 (60.6%)
T105 12860-12909 Sentence denotes  Complete PPE 46 (17.6%) 16 (34.8%) 30 (65.2%)
T106 12910-12968 Sentence denotes Confirmed COVID-19 12 (4.6%) 4 (33.3%) 8 (66.7%) 0.161
T107 12969-13034 Sentence denotes Pre-existing headache 110 (42.1%) 45 (40.9%) 65 (59.1%) 0.683
T108 13035-13046 Sentence denotes Comorbidity
T109 13047-13097 Sentence denotes  Allergy 34 (13.0%) 16 (47.1%) 18(52.9%) 0.331
T110 13098-13146 Sentence denotes  Asthma 17 (6.5%) 11 (64.7%) 6 (35.3%) 0.028
T111 13147-13197 Sentence denotes  Tobacco 41 (15.7%) 8 (19.5%) 33 (80.5%) 0.004
T112 13198-13260 Sentence denotes  Arterial hypertension 18 (6.9%) 9 (50.0%) 9 (50.0%) 0.789
T113 13261-13310 Sentence denotes  Cardiopathy 1 (0.4%) 0 (0.0%) 1 (100%) 0.419
T114 13311-13364 Sentence denotes  Dyslipidaemia 14 (5.4%) 7 (50.0%) 7 (50.0%) 0.76
T115 13365-13412 Sentence denotes  Diabetes 2 (0.8%) 1 (50.0%) 1 (50.0%) 0.76
T116 13413-13471 Sentence denotes  Thyroid disease 28 (10.7%) 9 (32.1%) 19 (67.9%) 0.402
T117 13472-13522 Sentence denotes  Anxiety 26 (10.0%) 6 (23.1%) 20 (76.9%) 0.072
T118 13523-13571 Sentence denotes  Others 16 (6.1%) 4 (25.0%) 12 (75.0%) 0.222
T119 13572-13586 Sentence denotes Other symptoms
T120 13587-13649 Sentence denotes  Sleep disturbance 79 (30.3%) 11 (13.9%) 68 (86.1%) 0.0001
T121 13650-13716 Sentence denotes  Loss of concentration 73 (28.0%) 14 (19.2%) 59 (80.8%) 0.0001
T122 13717-13773 Sentence denotes  Irritability 74 (28.4%) 18 (24.3%) 56 (75.7%) 0.002
T123 13774-13828 Sentence denotes  Photophobia 31 (11.9%) 8 (25.8%) 23 (74.2%) 0.097
T124 13829-13880 Sentence denotes  Sonophobia 24 (9.2%) 6 (25.0%) 18 75.0%) 0.128
T125 13881-13941 Sentence denotes  Sickness/vomiting 24 (9.2%) 11 (45.8%) 13 (54.2%) 0.503
T126 13942-14008 Sentence denotes FFP2, filtering face pieces; N95, 95% particle filtering capacity.
T127 14009-14121 Sentence denotes During April, the month prior to the survey, participants with ‘de novo’ headache presented a median of 12 (IQR:
T128 14122-14161 Sentence denotes 13) days of headache, median of 4 (IQR:
T129 14162-14291 Sentence denotes 3) days in the week prior to the survey, and the pain presented an average intensity on the Visual Analogue Scale (VAS) of 6 (SD:
T130 14292-14297 Sentence denotes 1.5).
T131 14298-14464 Sentence denotes In 74 (47.4%) subjects, the duration was from 1 to 4 hours; in 46 (29.5%), from 4 to 8 hours; in 21 (13.5%), from 8 to 12 hours; and in 15 (9.6%), more than 12 hours.
T132 14465-14561 Sentence denotes In subjects with previous headache, the duration of episodes was significantly higher (p=0.008).
T133 14562-14633 Sentence denotes The response to analgesics was good or very good in 61.4% of the cases.
T134 14634-14758 Sentence denotes Only two (1.3%) subjects had to consult the emergency department for headache, and no subject had been admitted to hospital.
T135 14759-14893 Sentence denotes With respect to the impact of headache in the work setting, lack of concentration on tasks was the main report (105 (66.5%) subjects).
T136 14894-14955 Sentence denotes Table 2 shows the main characteristics of ‘de novo’ headache.
T137 14956-15030 Sentence denotes Table 2 Characteristics of headache in healthcare worker (HCW) mask users
T138 15031-15136 Sentence denotes All HCW with de novo headache HCW without pre-existing headache HCW with pre-existing headache P value
T139 15137-15160 Sentence denotes (n=158) (n=93) (n=65)
T140 15161-15233 Sentence denotes Days with headache/month (SD) 13.2 (7.2) 13.0 (7.4) 13.5 (7.1) 0.746
T141 15234-15302 Sentence denotes Days with headache/week (SD) 3.8 (1.7) 3.8 (1.7) 3.9 (1.7) 0.827
T142 15303-15367 Sentence denotes Mean pain level, VAS (SD) 5.9 (1.5) 5.8 (1.5) 6.1 (1.4) 0.08
T143 15368-15398 Sentence denotes Duration time (hours) 0.008
T144 15399-15439 Sentence denotes  1–4 74 (47.4%) 52 (57.1%) 22 (33.8%)
T145 15440-15480 Sentence denotes  4–8 46 (29.5%) 23 (25.3%) 23 (35.4%)
T146 15481-15521 Sentence denotes  8–12 21 (13.5%) 12 (13.2%) 9 (13.8%)
T147 15522-15559 Sentence denotes  >12 15 (9.6%) 4 (4.4%) 11 (16.9%)
T148 15560-15587 Sentence denotes Analgesic response 0.342
T149 15588-15642 Sentence denotes  Good or very good 97 (61.4%) 61 (65.6%) 36 (55.4%)
T150 15643-15687 Sentence denotes  Regular 46 (29.1%) 23 (24.7%) 23 (35.4%)
T151 15688-15735 Sentence denotes  Bad or very bad 15 (9.5%) 9 (9.7%) 6 (9.2%)
T152 15736-15763 Sentence denotes Headache impact on HCW (SD)
T153 15764-15816 Sentence denotes  Occupational 4.0 (2.6) 3.5 (2.6) 4.6 (2.5) 0.02
T154 15817-15864 Sentence denotes  Family 4.4 (2.7) 4.1 (2.6) 4.9 (2.5) 0.084
T155 15865-15914 Sentence denotes  Personal 5.0 (2.6) 4.7 (2.7) 5.5 (2.4) 0.049
T156 15915-15962 Sentence denotes  Social 4.8 (2.8) 4.4 (2.8) 5.4 (2.7) 0.021
T157 15963-16013 Sentence denotes SD, Standar Deviation; VAS, Visual Analogue Scale.
T158 16014-16283 Sentence denotes Of the 65 subjects with a previous headache, 83.1% (54) indicated a modification in the characteristics of their habitual headaches, 81.0% (47) a change in location, 67.2% (39) in frequency, 36.2% (21) in intensity and 25.9% (15) in the response to habitual analgesics.
T159 16284-16521 Sentence denotes In the univariate analysis, the factors associated with the appearance of ‘de novo’ headache were age, female sex, type of profession, use of filter mask (KN95 or FFP2), work shift, being a tobacco user, suffering from anxiety or asthma.
T160 16522-16708 Sentence denotes In the multivariate analysis, the use of filter masks and the type of profession behaved as independent predictors of headache risk, while being asthmatic behaved as a protective factor.
T161 16709-16933 Sentence denotes The occurrence of headache is associated with the use of a filter mask (FFP2 or KN95), OR 2.14 (95% CI 1.07 to 4.32); being a health worker, OR 6.94 (95% CI 3.01 to 16.04) or a nurse, OR 2.09 (95% CI 1.18 to 3.72) (table 3).
T162 16934-17013 Sentence denotes Table 3 Univariate and multivariate analysis of factors of baseline conditions
T163 17014-17067 Sentence denotes Variables Univariate analysis Multivariate analysis
T164 17068-17108 Sentence denotes OR 95% CI P valúe OR 95% CI P valúe
T165 17109-17139 Sentence denotes Age 1.03 1.01 to 1.06 0.009
T166 17140-17180 Sentence denotes Female gender 2.41 1.31 to 4.45 0.005
T167 17181-17224 Sentence denotes Doctor Ref Ref 0.0001 Ref Ref <0.0001
T168 17225-17271 Sentence denotes Nurse 2.25 1.28 to 3.94 2.09 1.18 to 3.72
T169 17272-17323 Sentence denotes Other HCW 5.98 2.67 to 13.4 6.94 3.01 to 16.04
T170 17324-17405 Sentence denotes Filter mask versus surgical 2.08 1.07 to 4.07 0.026 2.14 1.07 to 4.32 0.027
T171 17406-17451 Sentence denotes Mornings and 24-hour duties Ref Ref 0.0001
T172 17452-17487 Sentence denotes Rotating shifts 3.35 1.81 to 6.23
T173 17488-17525 Sentence denotes Other work shifts 2.83 1.52 to 5.32
T174 17526-17585 Sentence denotes Asthma 0.33 0.12 to 0.92 0.03 0.29 0.09 to 0.89 0.026
T175 17586-17620 Sentence denotes Tobacco 3.13 1.39 to 7.01 0.003
T176 17621-17655 Sentence denotes Anxiety 2.34 0.91 to 6.05 0.063
T177 17656-17778 Sentence denotes 95%CI, 95% Confidence Interval; HCW, healthcare workers; HCW, healthcare worker; OR, odds ratio; Ref., Reference category.
T178 17779-17918 Sentence denotes According to the type of mask used, there was no difference in the number of days with headache in the month prior to the survey, 13.4 (SD:
T179 17919-17936 Sentence denotes 7.4) vs 12.6 (SD:
T180 17937-17977 Sentence denotes 6.9); nor in the previous week, 3.9 (SD:
T181 17978-17994 Sentence denotes 1.6) vs 3.6 (SD:
T182 17995-18048 Sentence denotes 1.7); but in the intensity according to VAS, 5.7 (SD:
T183 18049-18065 Sentence denotes 1.5) vs 6.5 (SD:
T184 18066-18080 Sentence denotes 1.2), p=0.004.
T185 18081-18372 Sentence denotes The impact of headache in subjects with a filter mask as opposed to surgical mask was worse in the four aspects evaluated by the Likert scale: occupational, 4.44 vs 3.81 (p=0.206); family, 5.10 vs 4.20 (p=0.065); personal, 5.64 vs 4.84 (p=0.05) and social, 5.46 vs 4.58 (p=0.076) (figure 1).
T186 18373-18478 Sentence denotes The impact was also greater in subjects with a previous headache in the four aspects evaluated (table 2).
T187 18479-18617 Sentence denotes Figure 1 Impact of headache in subjects with a filter mask as opposed to surgical mask in the four aspects evaluated by the Likert scale.
T188 18618-18720 Sentence denotes Likert scale rating: it indicates the degree of limitation due to headache in different areas of life.
T189 18721-18742 Sentence denotes 0: none; 10: maximum.
T190 18743-19041 Sentence denotes Regarding the evaluation of self-perceived work stress by means of the 12 items of the PPQ, individuals with ‘de novo’ headache versus those without headache have significantly worse scores in all aspects evaluated, except for the decrease in appetite where no significant differences are observed.
T191 19042-19152 Sentence denotes Figure 2 shows graphically the evaluation of occupational stress according to the presence of headache or not.
T192 19153-19354 Sentence denotes The use of a filter mask compared with surgical mask only implies a significantly worse score in two aspects: gastrointestinal discomfort (p=0.047) and greater sensation of extreme tiredness (p=0.004).
T193 19355-19475 Sentence denotes Figure 2 Evaluation of self-perceived work stress by means of the 12 items of the Psychosomatic Problems Questionnaire.
T194 19477-19487 Sentence denotes Discussion
T195 19488-19590 Sentence denotes The current COVID-19 pandemic has caused a substantial change in the workflow of health professionals.
T196 19591-19657 Sentence denotes One of the most important characteristics has been the use of PPE.
T197 19658-19757 Sentence denotes Masks are a critical preventive measure and are most essential when social distancing is difficult.
T198 19758-20009 Sentence denotes It is clear that adherence to universal mask policies reduces the transmission of SARS-CoV-2.14 But, according to the data obtained, we demonstrate a statistically significant association between the use of filter masks and the appearance of headache.
T199 20010-20130 Sentence denotes In the physiopathology of a new-onset headache, the exact mechanisms may be multiple, complex and not always well known.
T200 20131-20480 Sentence denotes Peripheral nociceptive structures and central sensitisation mechanisms may be involved in their development.15 16 The current International Headache Classification proposes, generically for secondary headaches, that the diagnostic criteria do not require remission or improvement of the underlying causal disorder before the diagnosis is formalised.
T201 20481-20780 Sentence denotes For acute processes, a close temporal relationship between the onset of the headache and the onset of the suspected causal disorder is usually sufficient.11 Following this classification, mask-associated headache would probably be a multifactorial disorder with unknown aetiopathogenesis at present.
T202 20781-20989 Sentence denotes Hypothetically, a number of factors may explain the association with filter mask use, including hypoxia, hypercapnia, local compression and mechanical phenomena, as well as anxiety about wearing the device.10
T203 20990-22206 Sentence denotes In the scientific literature there are not many studies that relate the use of face masks to changes in the concentration of oxygen and/or carbon dioxide (CO2), but it seems a plausible hypothesis due to the barrier element that is interposed in the physiological ventilation mechanism.17 In a Taiwanese cohort of 39 patients with end-stage renal disease who wore N95 masks during the 2002 SARS outbreak, the study found a significant reduction in arterial oxygen pressure from baseline and an increase in other respiratory adverse effects.18 Another study conducted in a cohort of 130 astronauts subjected to high CO2 pressures during controlled training showed a significantly higher incidence of headache in the exposed group, in addition to respiratory symptoms and difficulty in concentrating.19 At the University of Wollongong, a study on the effects of CO2 inhalation on workers wearing respiratory protection devices showed that high levels of CO2 were associated with feelings of discomfort and significantly reduced tolerance and time of device use.20 The effect on respiratory physiology and muscle performance of wearing training masks designed to simulate a variable altitude situation has been studied.
T204 22207-22623 Sentence denotes The results are mixed in terms of objective performance parameters, however, it seems that mask use reduces working speed and negatively influences levels of alertness and task focus.21 In 2014, a pilot study evaluated the consequences on respiratory physiology of surgical mask and N95 face mask use and the extent to which nasal inspiratory and expiratory resistance and discomfort were altered in the individuals.
T205 22624-22957 Sentence denotes Physiological changes such as increased respiratory resistances were observed after 3 hours of use.22 Headache associated with filter mask use could be included according to ICHD-311 in the section on headaches due to homeostatic disorders where those related to alteration of oxygen and CO2 partial pressure parameters are included.
T206 22958-23287 Sentence denotes Another phenomenon probably related to the physiopathology of headache after PPE use is the external compression that it generates, as recently reflected by the group of Ong et al.23 In most cases there is a temporal relationship between the use of devices and the headache, as well as the topographical location of the headache.
T207 23288-23676 Sentence denotes As with homeostatic changes, ICHD-3 typifies a type of headache attributable to uninterrupted compression or traction of pericranial soft tissues.11 Pressure or tractional forces from the mask, together with the accompanying straps, may lead to local tissue damage and exert an irritative effect on the underlying superficial sensory nerves innervating the face, head and cervical region.
T208 23677-23772 Sentence denotes There are several examples in the literature that would be consistent with this mechanism.10–24
T209 23773-23839 Sentence denotes The last factor to be mentioned is the level of anxiety or stress.
T210 23840-24097 Sentence denotes Multiple ways of relating stress and headache have been described, either as ‘de novo’ or as exacerbation in an individual with primary headache.25 In the case of the SARS-CoV-2 pandemic, healthcare workers may be affected by critical incident stress (CIS).
T211 24098-24265 Sentence denotes Critical incidents are events in which people witness or experience tragedy, death, serious injury or threatening situations, which can have a strong emotional impact.
T212 24266-24483 Sentence denotes The signs and symptoms of CIS can be physical, cognitive, emotional and behavioural.26 In our work, we observed that the level of stress in subjects with headache is significantly worse in all aspects measured by PPQ.
T213 24484-24612 Sentence denotes We also showed that the risk of developing headache is higher among nurses and other health professionals than among physicians.
T214 24613-24698 Sentence denotes The explanation for this result is complex, but there are three plausible hypotheses.
T215 24699-25102 Sentence denotes As a general rule, doctors live with a higher level of stress in the course of their work, and therefore, situations considered conflicting do not increase their usual stress threshold excessively.27 It could also be explained by the use of negative coping strategies in some professional groups as opposed to others28; these strategies, not measured in our work, would be related to professional level.
T216 25103-25486 Sentence denotes The third potential explanation, in line with some published studies, is that the higher risk of headache among nurses and other health professionals than in the medical group, is due to the differential characteristics of the workers' occupation, which would involve the use of other devices, cleaning materials, activities with greater energy expenditure or changing work shifts.29
T217 25487-25676 Sentence denotes Different factors or comorbidities that may influence the development of headache have been described in the literature.30 If we look at risk markers, age and sex deserve special attention.
T218 25677-26501 Sentence denotes The female sex is closely related to the development of ‘de novo’ headache.31 Age is a determining factor in the classification of headache according to the International Headache Society.11 Several studies have shown that pain intensity,32 the degree of headache disability and the possibility of secondary headache occurrence are age-related factors.33 In terms of other individually modifiable risk factors, the relationship between blood pressure changes and primary headache should be highlighted, as they share mechanisms of action such as vascular endothelial dysfunction or poor cardiovascular autonomic regulation.34 However, in our study we did not find a clear association between different comorbidities of the individual and the appearance of headache, except for tobacco consumption in the univariate analysis.
T219 26502-26615 Sentence denotes In a review of the relationship between smoking and the occurrence of headache, controversial data were obtained.
T220 26616-26760 Sentence denotes The studies are mostly retrospective and limited, and there is no definite evidence that tobacco is an independent cause of headache occurrence.
T221 26761-26961 Sentence denotes However, most patients with migraine define it as a trigger.35 Headache is one of the most pronounced symptoms in patients suffering from asthma, a fact that has been described in a few papers so far.
T222 26962-27148 Sentence denotes In a study of 93 patients, a statistically significant difference was found in this area, as 62.4% of asthmatics had headache, whereas in the control group the percentage was only 32.8%.
T223 27149-27580 Sentence denotes Other factors such as the use of steroid inhalers, the presence of rhinitis, conjunctivitis or respiratory parameters, such as forced expiratory volume in one second, were studied and characterised.36 In our study, being asthmatic would act as a protective factor against headache associated with mask use, perhaps because of a greater tolerance to hypoxia, and therefore a higher threshold for developing headache for this reason.
T224 27581-27682 Sentence denotes It is especially important to discuss possible methods to reduce the impact of PPE-induced headaches.
T225 27683-28145 Sentence denotes Our findings are in agreement with multiple studies showing that headache triggers are often associated with a change in homeostasis, underscoring the importance of addressing these factors to optimise headache control.37 For example, encouraging the use of powered air-purifying respirators (PAPRs) is a method for healthcare workers working in high-risk areas and for long periods, since the PAPR provides additional safety and reduces the accumulation of CO2.
T226 28146-28360 Sentence denotes On the other hand, we recognise that the conventional N95 face mask fit considers only the overall fit factor and does not take into account the level of tolerability, especially when worn for long periods of time.
T227 28361-28752 Sentence denotes Since current mask designs can cause headaches and affect compliance, the administrators should think about devising new work schedules for healthcare workers (like shorter working hours) and for people who need to wear a filter mask.38 Through novel engineering solutions, next-generation face masks need to be better designed with priority on tolerability and less predisposed to headache.
T228 28754-28765 Sentence denotes Limitations
T229 28766-28904 Sentence denotes Our study has some limitations that should be noted: the sample is one of convenience and there has been no previous probability sampling.
T230 28905-28970 Sentence denotes We could not include or under-represent some professional groups.
T231 28971-29071 Sentence denotes The study is cross-sectional, which helps us to formulate hypotheses, but we cannot prove causality.
T232 29072-29331 Sentence denotes We have not taken into account the temporal evolution of the headache in the health professionals who present it, nor have we taken into account other external factors that may influence the headache, such as the exact conditions of the site and type of work.
T233 29332-29601 Sentence denotes The last limitation is that we have not considered other confounding variables that could potentially condition a headache, such as dehydration due to the continued use of full PPE in a hot environment or lifestyle, or diet changes derived from stress or lack of sleep.
T234 29603-29613 Sentence denotes Conclusion
T235 29614-29796 Sentence denotes In our study, we described the occurrence of ‘de novo’ headache with the use of filter masks and their negative impact on multiple dimensions of the life of healthcare professionals.
T236 29797-29949 Sentence denotes We propose headache associated with the use of this type of mask as a new subtype of headache, of a multifactorial nature and complex aetiopathogenesis.
T237 29950-30213 Sentence denotes Since the use of these devices will tend to become more widespread due to the implications of the pandemic, we believe it is important to promote prevention and protection strategies that guarantee the safety of workers, without undermining their quality of life.
T238 30215-30307 Sentence denotes We want to thank Juan Rodrigo Ross for his invaluable help in the preparation of this paper.
T239 30308-30406 Sentence denotes Also, to all colleagues, health workers who have responded with great rigour to the questionnaire.
T240 30407-30421 Sentence denotes Collaborators:
T241 30422-30439 Sentence denotes Juan Rodrigo Ross
T242 30440-30579 Sentence denotes Contributors: JMR-M designed the study, collected data, made statistical analysis plan, wrote the first draft and submitted the manuscript.
T243 30580-30649 Sentence denotes DC collected data and edited the manuscript for intellectual content.
T244 30650-30721 Sentence denotes AG-P collected data and edited the manuscript for intellectual content.
T245 30722-30791 Sentence denotes BR collected data and edited the manuscript for intellectual content.
T246 30792-30862 Sentence denotes PMS collected data and edited the manuscript for intellectual content.
T247 30863-30932 Sentence denotes RH collected data and edited the manuscript for intellectual content.
T248 30933-31002 Sentence denotes AR collected data and edited the manuscript for intellectual content.
T249 31003-31073 Sentence denotes ABC collected data and edited the manuscript for intellectual content.
T250 31074-31082 Sentence denotes Funding:
T251 31083-31224 Sentence denotes The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
T252 31225-31245 Sentence denotes Competing interests:
T253 31246-31260 Sentence denotes None declared.
T254 31261-31293 Sentence denotes Patient consent for publication:
T255 31294-31307 Sentence denotes Not required.
T256 31308-31336 Sentence denotes Data availability statement:
T257 31337-31396 Sentence denotes All data relevant to the study are included in the article.
T258 31397-31565 Sentence denotes No obstante, all the data with which this work has been prepared are available to any researcher upon reasonable and understandable request to the corresponding author.