Table 1.
General characteristics of the participants
| Characteristics | Total participants | ||
| Migraine (n, %) | Control (n, %) | P value | |
| Age (years) | 1.000 | ||
| 20–24 | 1994 (4.8) | 7976 (4.8) | |
| 25–29 | 2649 (6.4) | 10 596 (6.4) | |
| 30–34 | 3640 (8.8) | 14 560 (8.8) | |
| 35–39 | 4309 (10.4) | 17 236 (10.4) | |
| 40–44 | 4859 (11.7) | 19 436 (11.7) | |
| 45–49 | 5187 (12.5) | 20 748 (12.5) | |
| 50–54 | 4512 (10.9) | 18 048 (10.9) | |
| 55–59 | 3508 (8.4) | 14 032 (8.4) | |
| 60–64 | 3209 (7.7) | 12 836 (7.7) | |
| 65–69 | 3049 (7.3) | 12 196 (7.3) | |
| 70–74 | 2328 (5.6) | 9312 (5.6) | |
| 75–79 | 1423 (3.4) | 5692 (3.4) | |
| 80–84 | 651 (1.6) | 2604 (1.6) | |
| 85+ | 267 (0.6) | 1068 (0.6) | |
| Sex | 1.000 | ||
| Male | 10 476 (25.2) | 41 904 (25.2) | |
| Female | 31 109 (74.8) | 124 436 (74.8) | |
| Income | 1.000 | ||
| 1 (lowest) | 837 (2.0) | 3348 (2.0) | |
| 2 | 3170 (7.6) | 12 680 (7.6) | |
| 3 | 3004 (7.2) | 12 016 (7.2) | |
| 4 | 3131 (7.5) | 12 524 (7.5) | |
| 5 | 3345 (8.0) | 13 380 (8.0) | |
| 6 | 3615 (8.7) | 14 460 (8.7) | |
| 7 | 3908 (9.4) | 15 632 (9.4) | |
| 8 | 4411 (10.6) | 17 644 (10.6) | |
| 9 | 4908 (11.8) | 19 632 (11.8) | |
| 10 | 5456 (13.1) | 21 824 (13.1) | |
| 11 (highest) | 5800 (13.9) | 23 200 (13.9) | |
| Region of residence | 1.000 | ||
| Urban | 17 959 (43.2) | 71 836 (43.2) | |
| Rural | 23 626 (56.8) | 94 504 (56.8) | |
| Hypertension | 16 209 (39.0) | 64 836 (39.0) | 1.000 |
| Diabetes | 7261 (17.5) | 29 044 (17.5) | 1.000 |
| Dyslipidaemia | 12 837 (30.9) | 51 348 (30.9) | 1.000 |
| Congestive heart failure | 2030 (4.9) | 6761 (4.1) | <0.001* |
| Myocardial infarction | 913 (2.2) | 3330 (2.0) | 0.013* |
| Peripheral vascular disease | 7942 (19.1) | 20 217 (12.2) | <0.001* |
| Pulmonary disease | 29 540 (71.0) | 94 811 (57.0) | <0.001* |
| Liver disease | 5087 (12.2) | 15 317 (9.2) | <0.001* |
| Depression | 7808 (18.8) | 15 269 (9.2) | <0.001* |
| Haemorrhagic stroke | 295 (0.7) | 1113 (0.7) | 0.370 |
| Ischaemic stroke | 964 (2.3) | 3294 (2.0) | <0.001* |
The crude and adjusted HRs for haemorrhagic stroke were 1.06 (95% CI=0.93 to 1.21, P=0.369) and 1.10 (95% CI=0.96 to 1.25, P=0.172), respectively, in the migraine group (table 2). The crude and adjusted HRs for ischaemic stroke were 1.17 (95% CI=1.09 to 1.26) and 1.18 (95% CI=1.08 to 1.25), respectively, in the migraine group (each P<0.001).
*χ2 test. Differences were considered significant at P<0.05.