Hypertension and migraine comorbidity: prevalence and risk of cerebrovascular events: evidence from a large, multicenter, cross-sectional survey in Italy (MIRACLES study)

OBJECTIVES: To estimate the prevalence of hypertension-migraine comorbidity; to determine their demographic and clinical characteristics versus patients with hypertension or migraine alone; and to see whether a history of cerebrovascular events was more common in the comorbidity group. METHODS: The MIRACLES, multicenter, cross-sectional, survey included 2973 patients with a known diagnosis of hypertension or migraine in a general practitioner setting in Italy. RESULTS: Five hundred and seventeen patients (17%) suffered from hypertension-migraine comorbidity, whereas 1271 (43%) suffered from hypertension only, and 1185 (40%) from migraine only. In the comorbidity group, the onset of comorbidity occurred at about 45 years of age, with migraine starting significantly later than in the migraine-only group, and hypertension significantly before than in the hypertension-only group; a familial history of both hypertension and migraine had a significantly higher frequency as compared with the hypertension and migraine group. Compared to hypertension (3.1%) and migraine (0.7%), the comorbidity group had a higher prevalence (4.4%) of history of cerebrovascular events, with an odds ratio of a predicted history of stroke/transient ischemic attack (TIA) of 1.76 [95% confidence interval (CI) 1.01-3.07] compared to the hypertension group. In patients without other recognized risk factors for stroke, stroke/TIA occurred more frequently in the comorbidity group, compared to the hypertension group. In the age range 40-49 years, prevalence of history of stroke/TIA was five-fold greater (4.8% in comorbidity vs. 0.9% in hypertension group). CONCLUSION: This cross-sectional study indicates that the prevalence of comorbidity hypertension-migraine is substantial and that patients with comorbidity have a higher probability of history of cerebrovascular events, compared to hypertensive patients