Page 151 - Migraine, the heart and the brain

The post-ictal impact of a migraine attack on cognition
Letters appeared in black on a white background, measured 3 x 3 cm and were seen from a distance of about 60 cm. Each letter was shown for 1000 ms, followed by 1000 ms blank. Reaction time to target letters and percentage of correct responses were recorded, with accuracy being the main dependent variable.
Patient characteristics
During a face-to-face interview, migraine characteristics were evaluated for the preceding attack as well as migraine history and general health. The visual analogue scale was used by participants to report the pain experienced during the preceding attack, with a value of 0 implying no pain and a value of 10 implying agonizing pain. Furthermore, preceding migraine severity was assessed by a 4-point scale; no pain, mild pain, moderate pain, or severe pain. Educational level was dichotomized to low (primary school) vs. higher.
Statistical analysis
Baseline characteristics were analysed using t-tests for continuous variables and chi- squared/Fisher exact tests for dichotomous variables. Reaction time and percentage
correct for all computerized tasks were analysed using analysis of variance (ANOVA)
for repeated measurements. For the omnibus analysis of the global-local task, a 3 x 2
x 2 x 2 ANOVA was used with session (3), level (global/local, 2), and congruence (2) as
within subject factors and group (migraine vs. control) as between-subject factor. The
paired sample t-test was used for comparing the global-local effect in each group. For
the omnibus analysis of each of the three indicators of the ANT, 3 x 2 x 2 ANOVAs were
used with session (3) and condition (2) as within-subjects factors and group (migraine
vs. control) as between subjects factor. For the omnibus analysis of the N-back task a 8 3 x 4 x 2 design was used with session (3) and level (4: 0, 1, 2, or 3) as within-subjects
factors and group (migraine vs. control) as between-subject factor. t-tests were used for more detailed comparisons. The signi cance level was set to p = 0.05 for all statistical tests.
results
Demographics of migraine patients and controls did not differ signi cantly, as shown in Table 1. Mean age of patients was 58 years and 13 (81%) had migraine without aura. The characteristics of the attack preceding the rst test are shown in Table 2. None
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