Page 46 - Migraine, the heart and the brain

Chapter 2
lesions (migraine group, 2.5% vs control group, 3.5%; P = .69; Table 2). Of those with infarcts, 21% of those in the control group vs none in the control group reported a history of clinical stroke (P = .10).
Cognitive Changes
There were no differences in cognitive functioning between groups at follow-up (mean composite Z score, migraine group, 1.2 vs control group, 0; adjusted P = .90; 95% CI, −2.0 to 2.0). At follow-up, deep white matter hyperintensity load was not associated with cognitive performance (mean composite Z score high load, −3.7 vs low load, 1.4; adjusted P = .07; 95% CI, −4.4 to 0.2; men and women were analyzed together, see also eTable3 for original clinical scores of the separate subtest domains). Presence of migraine did not influence this association (adjusted P = .30; 95% CI, −2.0 to 2.1). Individuals with a high deep white matter hyperintensity load at baseline did not experience greater change in cognitive function at the 9-year follow-up than those without a high load at baseline (mean composite Z score, −0.5 vs 0.2; adjusted P = .4; 95% CI, -1.7 to 0.7). Similarly, there were no signi cant differences between groups with respect to tests of individual cognitive domains (eTable3).
Assessment of cognitive performance
Cognitive performance was evaluated by validated, widely used, cognitive tests in a xed order. The test battery, administered by four trained medical students, was the same for both time points (test protocol and methods were the same for baseline and follow-up) and included the 15 word Verbal Learning Test (Rey, 1985); abbreviated Stroop test (Stroop, 1935) consisting of three subtasks; verbal Fluency test (Miller, 1984); Letter Digit Substitution Test (Van der E, 2006), which is a modi ed version of the Symbol Digit Modalities Test; and Purdue pegboard test (Tif n, 1948). In follow- up investigation, the Block Design Test from the WAIS-III test battery (Wechsler, 1981) was added. Higher score indicates better cognitive performance. The results of these tests were normalized by calculation of Z-scores based on total sample means and standard deviations, and added up per cognitive domain. The composite cognitive score was calculated for baseline as well as follow-up time point by adding up the separate domain Z-scores.
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