Demographics and clinical characteristics of the study subjects before and after propensity score matching
| Variables * | Before propensity-score matching | Propensity-score matched | StD‡ | |||
| Non-migraine (n=503 070) | Migraine (n=8880) | P value† | Non-migraine (n=7156) | Migraine (n=7156) | ||
| Age (SD), years | 42.2 (16.6) | 42.1 (14.5) | 0.876 | 40.8 (14.1) | 40.8 (14.1) | 0.001 |
| Male, n (%) | 274 757 (54.6) | 2192 (24.7) | <0.001 | 1780 (24.9) | 1780 (24.9) | 0.000 |
| Monthly income, NTD, n (%) | ||||||
| <15 840 | 234 301 (46.6) | 4033 (45.4) | 0.031 | 3164 (44.2) | 3225 (45.1) | 0.017 |
| 15 840–25 000 | 153 457 (30.5) | 2979 (33.6) | <0.001 | 2266 (31.7) | 2343 (32.7) | 0.023 |
| >25 000 | 115 312 (22.9) | 1868 (21.0) | <0.001 | 1726 (24.1) | 1588 (22.2) | 0.046 |
| Clinic visit frequency, visits per year (SD) | 13.5 (12.2) | 26.3 (19.2) | <0.001 | 18.8 (12.4) | 24.3 (17.8) | 0.361 |
| 0, n (%) | 6168 (1.2) | 18 (0.2) | <0.001 | 13 (0.18) | 14 (0.2) | 0.003 |
| 1–5, n (%) | 105 443 (21.0) | 370 (4.2) | <0.001 | 335 (4.68) | 341 (4.8) | 0.004 |
| 6–10, n (%) | 132 280 (26.3) | 1100 (12.4) | <0.001 | 1016 (14.2) | 1004 (14.0) | 0.005 |
| >10, n (%) | 259 186 (51.5) | 7392 (83.2) | <0.001 | 5792 (80.94) | 5797 (81.0) | 0.002 |
| CCIS (SD) | 1.1 (1.8) | 2.0 (2.1) | <0.001 | 1.3 (1.7) | 1.7 (1.8) | 0.177 |
| 0, n (%) | 269 349 (53.5) | 2360 (26.6) | <0.001 | 2964 (41.4) | 2218 (31.0) | 0.218 |
| 1, n (%) | 104 891 (20.9) | 2215 (24.9) | <0.001 | 1802 (25.2) | 1946 (27.2) | 0.046 |
| 2, n (%) | 52 287 (10.4) | 1639 (18.5) | <0.001 | 1096 (15.3) | 1295 (18.1) | 0.075 |
| ≥3, n (%) | 76 543 (15.2) | 2666 (30.0) | <0.001 | 1294 (18.1) | 1697 (23.7) | 0.139 |
| No of serum creatinine test | 2.6 (5.5) | 5.5 (9.4) | <0.001 | 4.0 (5.9) | 4.0 (5.4) | 0.011 |
| Comorbid conditions, n (%) | ||||||
| Hypertension | 61 933 (12.3) | 1488 (16.8) | <0.001 | 831 (11.6) | 960 (13.4) | 0.055 |
| Diabetes mellitus | 27 982 (5.6) | 403 (4.5) | <0.001 | 210 (2.9) | 297 (4.2) | 0.066 |
| Hyperlipidaemia | 35 314 (7.0) | 832 (9.4) | <0.001 | 482 (6.7) | 555 (7.8) | 0.039 |
| CAD | 43 242 (8.6) | 1483 (16.7) | <0.001 | 726 (10.2) | 819 (11.4) | 0.042 |
| CHF | 6056 (1.2) | 86 (1.0) | 0.044 | 43 (0.6) | 57 (0.8) | 0.023 |
| Stroke | 13 574 (2.7) | 694 (7.8) | <0.001 | 149 (2.1) | 249 (3.5) | 0.085 |
| COPD | 33 947 (6.8) | 694 (7.8) | <0.001 | 505 (7.1) | 471 (6.6) | 0.018 |
| PAOD | 1932 (0.4) | 43 (0.5) | 0.131 | 22 (0.3) | 31 (0.4) | 0.021 |
| Urinary calculi | 5129 (1.0) | 172 (1.9) | <0.001 | 85 (1.2) | 92 (1.3) | 0.009 |
| Medications, n (%) | ||||||
| Anti-diabetic agents | 22 619 (4.5) | 299 (3.4) | <0.001 | 137 (1.9) | 225 (3.1) | 0.078 |
| Diuretics | 24 248 (4.8) | 487 (5.5) | 0.004 | 229 (3.2) | 324 (4.5) | 0.069 |
| ACEIs/ARBs | 37 240 (7.4) | 736 (8.3) | 0.002 | 362 (5.1) | 495 (6.9) | 0.078 |
| Statins | 17 566 (3.5) | 375 (4.2) | <0.001 | 166 (2.3) | 248 (3.5) | 0.068 |
| Anti-migraine agents§ | 43 228 (8.6) | 4026 (45.3) | <0.001 | 1036 (14.5) | 2877 (40.2) | 0.603 |
| Acute medicines | ||||||
| NSAIDs | 82 105 (16.3) | 4084 (46.0) | <0.001 | 2630 (36.8) | 2702 (37.8) | 0.021 |
| Analgesic drugs other than NSAIDs¶ | 36 143 (7.2) | 2215 (24.9) | <0.001 | 1063 (14.9) | 1215 (17.0) | 0.058 |
| Preventive medicines | ||||||
| Beta-blockers | 43 027 (8.6) | 2289 (25.8) | <0.001 | 1118 (15.6) | 1183 (16.5) | 0.025 |
| SSRI | 7490 (1.5) | 733 (8.3) | <0.001 | 208 (2.9) | 481 (6.7) | 0.179 |
| Propranolol | 14 956 (3.0) | 1538 (17.3) | <0.001 | 504 (7.0) | 975 (13.6) | 0.217 |
| SNRI | 7321 (1.5) | 804 (9.1) | <0.001 | 156 (2.2) | 523 (7.3) | 0.243 |
| Flunarizine | 4029 (0.8) | 1250 (4.1) | <0.001 | 74 (1.0) | 856 (12.0) | 0.455 |
*Variables are expressed as mean±SD or n (%).
†Two-sided t-test or χ2 test between the migraine and non-migraine cohorts.
‡StD, standardised difference of greater than 0.1 is considered important imbalance.
§Acute medicines include ergot alkaloids and selective serotonin agonists, preventive medicines include beta-blockers, antiepileptics (topiramate and valproate), tricyclic antidepressants, selective serotonin reuptake inhibitors, serotonin–norepinephrine reuptake inhibitors and other anti-migraine drugs (http://www.migraine.org.uk/ and Silberstein SD, et al. Evidence-based guideline update: Pharmacologic treatment for episodic migraine prevention in adults. Neurology 2012;78:1337–1345).
¶Includes aspirin, acetaminophen and cyclooxygenase-2 inhibitors.
ACEIs, angiotensin-converting enzyme inhibitors; ARBs, angiotensin II receptor blockers; CAD, coronary artery disease; CCIS, Charlson Comorbidity Index score; CHF, congestive heart failure; COPD, chronic obstructive pulmonary disease; NSAIDs, non-steroidal anti-inflammatory drugs; NTD, new Taiwan dollars; PAOD, peripheral artery occlusive disease; SNRI, serotonin–norepinephrine reuptake inhibitor; SSRI, selective serotonin reuptake inhibitors; StD, standardised difference.