Page 35 - Migraine, the heart and the brain

Covariates and Definitions
Sociodemographic and medical history characteristics were assessed by interview.
Educational level was dichotomized into low, primary school or less than vocational
education, and high, more than higher vocational or professional education, college, 2 or university. A diagnosis of diabetes or hypertension was based on patient report of
a physician’s diagnosis.
Statistical Analysis
Differences in the distributions and means of measured characteristics among the study groups were assessed with X2, 2-tailed Fisher exact, unpaired t, and Mann- Whitney U tests and 1-way analyses of variance where appropriate. Using logistic regression, the risk for MRI outcome measures was examined by migraine diagnosis (yes/ no) and subtype of migraine (with and without aura vs controls), controlling for age, sex, educational level, hypertension, and diabetes. Statistical interactions of hypertension and diabetes for associations of migraine and MRI measured outcomes were tested for by adding the interaction terms to the models. Analyses of deep white matter hyperintensity volumes were a priori strati ed by sex, based on earlier ndings of increased association of migraine with MRI lesions only among women.4 Likewise, infarct analyses were a priori strati ed by anterior or posterior vascular territory. In logistic regression models, exploratory analyses were conducted on the effects of several migraine characteristics on measures of lesion progression. Associations between deep white matter hyperintensity load and normalized scores of the baseline and follow-up cognitive tests were assessed using linear regression models, adjusting for age, sex, and educational level (model 1) and additionally for migraine (model 2) to assess the effect of migraine diagnosis. Data were analyzed using the statistical software package for social sciences (SPSS, version 17.0. for Windows).
results
Study Population
A total of 411 of 435 (95%) of baseline participants were successfully recontacted; 14 participants had moved, 4 were lost to civil registry information, and 6 had died (eTable 1).
Structural Brain Changes in Migraine
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