Background
Methods
Study population and design
Migraine
Dementia
Type of diagnoses | ICD-8 codes | ICD-10 codes |
---|---|---|
Dementia | ||
Alzheimer’s disease | 290.10 | F00.0–00.9, G30.0–30.9 |
Vascular dementia | 293.09–19 | F01.0–01.9 |
Frontotemporal dementia | 290.11 | F02.0 |
Lewy body dementia | G31.8 | |
Unspecified and other dementia | 290.09, 290.18–19 | F03.9, G31.9 |
Headache | ||
Cephalalgia | 791.99 | DR51, DR519 |
Other headache syndromes | G44 | |
Cluster headache syndrome | G44.0 | |
Vascular headache | G44.1 | |
Tension-type headache | G44.2 | |
Chronic post-traumatic headache | G44.3 | |
Drug-induced headache | G44.4 | |
Other specified headache syndromes | G44.8 | |
Psychiatric | ||
Schizophrenia, schizotypal and delusional disorders | 295.09–99, 297.09–99 | F20-F29 |
Mood affective disorders | 296.09–99, 790.29 | F30-F39 |
Other or unspecified psychoses | 298.09–99, 299.00–09 | |
Neuroses | 300.49–99 | |
Transient situational disturbances | 307.99 | |
Acute stress reactions | F43.0 | |
Post-traumatic stress disorders | F43.1 | |
Adjustment disorders | F43.2 | |
Other stress reactions | F43.8 | |
Unspecified stress reactions | F43.9 | |
Charlson Comorbidity Index | ||
Myocardial infarction | 410 | I21, I22, I23 |
Heart failure | 427.09, 427.10, 427.11, 427.19, 428.99, 782.49 | I50, I110, I130, I132 |
Peripheral vascular disease | 440, 441, 442, 442, 444, 445 | I70, I71, I72, I74, I77 |
Cerebral vascular accident | 430–438 | I60-I69, G45, G46 |
Pulmonary disease | 490–493, 515–518 | J40-J47, J60-J67, J684, J701, J703. J841, J920, J961, J982, J983 |
Connective tissue disorder | 712, 716, 734, 446, 135.99 | M05, M06, M08, M09, M30, M31, M32, M33, M34, M35, M36, D86 |
Ulcer disease | 530.91, 530.98, 531–534 | K221, K25-K28 |
Mild liver disease | 571, 573.01, 573.04 | B18, K700–703, K709, K71, K73, K74, K760 |
Diabetes | 249.00, 249.06, 249.07, 249.09, 250.00, 250.06, 250.07, 250.09 | E100, E101, E109, E110, E111, E119 |
Hemiplegia | 334 | G81, G82 |
Renal disease | 403, 404, 580–584, 590.09, 593.19, 753.10, 753.20, 792 | I12, I13, N00, N06, N07, N11, N14, N17-N19, Q61 |
Diabetes with complications | 249.01–249.05, 249.08, 250.01–250.05, 250.08 | E102-E108, E112-E118 |
Cancer | 140–194 | C00-C75 |
Leukemia | 204–207 | C91-C95 |
Lymphoma | 200–203, 275.59 | C81-C85, C88, C90, C96 |
Severe liver disease | 070.00, 070.02, 070.04, 070.06, 070.08, 573.00, 456.00–456.10 | B150, B160, B162, B190, K704, K72, K766, I85 |
Metastatic cancer | 195–199 | C76, C81 |
HIV | 079.83 | B21-B24 |
Covariates
Statistical analyses
Results
Any ICD-8 and ICD-10 migraine diagnosis | Comparison cohort | Any ICD-8 migraine diagnosis | Any ICD-10 migraine diagnosis | Migraine without aura in ICD-10 | Migraine with aura in ICD-10 | |
---|---|---|---|---|---|---|
Characteristics | n = 10,857 (17%) | n = 51,721 (83%) | n = 2183 (20%) | n = 8674 (80%) | n = 2845 (26%) | n = 1698 (16%) |
Age, median (IQR) | ||||||
Years | 49 (44–53) | 49 (44–53) | 43 (38–47) | 50 (46–54) | 50 (46–54) | 51 (47–54) |
Sex, No. (%) | ||||||
Women | 7975 (73) | 38,104 (74) | 1574 (72) | 6401 (74) | 2239 (79) | 1200 (71) |
Country of origin, No. (%) | ||||||
Danish | 10,087 (93) | 49,177 (95) | 2118 (97) | 7970 (92) | 2615 (92) | 1586 (93) |
Western | 272 (2) | 1399 (3) | 35 (2) | 237 (3) | 76 (3) | 55 (3) |
Non-Western | 498 (5) | 1145 (2) | 31 (1) | 467 (5) | 154 (5) | 57 (3) |
Marital status, No. (%) | ||||||
Unmarried | 3029 (28) | 15,027 (29) | 566 (26) | 2,463 (28) | 824 (29) | 432 (25) |
Educational level, No. (%) | ||||||
Low | 3799 (35) | 17,757 (34) | 976 (45) | 2,823 (32) | 904 (32) | 530 (31) |
Medium | 4173 (38) | 20,366 (40) | 814 (37) | 3359 (39) | 1089 (38) | 656 (39) |
High | 2885 (27) | 13,598 (26) | 394 (18) | 2492 (29) | 852 (30) | 512 (30) |
Previous headache diagnoses, No. (%) | ||||||
Yes | 600 (6) | 524 (1) | 63 (3) | 537 (6) | 210 (7) | 86 (5) |
Previous psychiatric diagnoses, No. (%) | ||||||
Yes | 748 (7) | 2185 (4) | 126 (6) | 622 (7) | 191 (7) | 115 (7) |
Charlson Comorbidity Index, No. (%) | ||||||
0 | 10,059 (93) | 48,729 (94) | 2135 (98) | 7925 (91) | 2,577 (91) | 1542 (91) |
≥1 | 789 (7) | 2992 (6) | 49 (2) | 749 (9) | 268 (9) | 156 (9) |
Migraine contacts, median (IQR) | ||||||
Number | 1 (1–2) | – | 1 (1–1) | 1 (1–2) | 1 (1–2) | 1 (1–2) |
Analysis | Migraine diagnosis | No. of individuals | Minimum follow-up years between migraine and dementia | Dementia cases/ person-years | Model 1 HR (95% CI) | Model 2 HR (95% CI) |
---|---|---|---|---|---|---|
Main analysis | None | 51,721 | ≥ 1 | 640/402,006 | 1.00 | 1.00 |
Any | 10,857 | ≥ 1 | 207/83,926 | 1.55 (1.32–1.81) | 1.50 (1.28–1.76) | |
Migraine without aura | 2845 | ≥ 1 | 34/19,995 | 1.21 (0.85–1.72) | 1.19 (0.84–1.70) | |
Migraine with aura | 1698 | ≥ 1 | 33/11,604 | 2.13 (1.50–3.03) | 2.11 (1.48–3.00) | |
All other migraine types | 6314 | ≥ 1 | 140/52,328 | 1.55 (1.29–1.86) | 1.48 (1.23–1.78) | |
Sensitivity analysis | Any | 10,773 | ≥ 5 | 205/81,326 | 1.55 (1.32–1.81) | 1.50 (1.28–1.76) |
Any | 10,198 | ≥ 10 | 185/74,055 | 1.49 (1.26–1.75) | 1.43 (1.21–1.69) | |
Any | 9677 | ≥ 15 | 174/69,486 | 1.53 (1.29–1.82) | 1.48 (1.25–1.76) | |
Any | 9271 | ≥ 20 | 164/67,344 | 1.57 (1.32–1.87) | 1.53 (1.28–1.83) | |
Additional refinement of exposure | Number of contacts | |||||
Migraine contactsa | 0 | 40,718 | ≥ 1 | 499/313,832 | 1.00 | 1.00 |
1 | 6233 | ≥ 1 | 121/50,101 | 1.44 (1.18–1.76) | 1.38 (1.13–1.69) | |
2 | 1428 | ≥ 1 | 25/10,432 | 1.63 (1.09–2.43) | 1.51 (1.01–2.27) | |
≥ 3 | 890 | ≥ 1 | 6/5438 | 0.94 (0.42–2.11) | 0.89 (0.40–2.00) | |
Hospital contactsb | 0 | 51,721 | ≥ 1 | 640/402,006 | 1.00 | 1.00 |
1 | 7836 | ≥ 1 | 162/63,184 | 1.53 (1.29–1.82) | 1.49 (1.25–1.77) | |
2 | 1810 | ≥ 1 | 37/13,305 | 1.89 (1.36–2.64) | 1.80 (1.29–2.51) | |
≥ 3 | 1211 | ≥ 1 | 8/7437 | 0.92 (0.46–1.85) | 0.89 (0.44–1.79) |
Characteristics | No. of individuals | Dementia cases/person-years | HR (95% CI) | P value for interaction |
---|---|---|---|---|
Sex | 0.6a | |||
Men | ||||
Without migraine | 13,617 | 186/102,687 | 1.00 | |
With migraine | 2882 | 57/21,913 | 1.39 (1.03–1.88) | |
Women | ||||
Without migraine | 38,104 | 454/299,319 | 1.00 | |
With migraine | 7975 | 150/62,013 | 1.54 (1.28–1.86) | |
Educational level | 0.8b | |||
Low | ||||
Without migraine | 17,757 | 292/147,296 | 1.00 | |
With migraine | 3799 | 92/31,028 | 1.47 (1.16–1.87) | |
Medium | ||||
Without migraine | 20,366 | 229/159,620 | 1.00 | |
With migraine | 4173 | 72/32,484 | 1.45 (1.11–1.89) | |
High | ||||
Without migraine | 13,598 | 119/95,090 | 1.00 | |
With migraine | 2885 | 43/20,414 | 1.64 (1.16–2.33) |