Interictal Dysfunctions of Attention, Vigilance, and Executive Functions in Migraine and Their Reversal by Preventive Treatment: A longitudinal Controlled Study

To assess attention, vigilance, and executive functions in migraine patients during headache-free (interictal) periods and in healthy controls without migraine and to study the impact of migraine preventive treatment on these cognitive functions. Preventive drug-naive migraine patients, aged ≥18 years, without a history of medication overuse were studied and compared to non-migraine controls. Psychiatric comorbidity was screened by Patient Health Questionnaire-9, and those who screened positive were evaluated further by specific scales. The Epworth Sleepiness Scale assessed subjective complaints of sleep quality. Cognitive functions were assessed by Mini-Mental State Examination (MMSE), digit span forward and backward (DS-F, DS-B), trail-making tests (TMT-A and B) and Stroop word (SW), Stroop color (SC), and Stroop interference (SI) tests. Cognitive test scores at the end of 6 months following treatment were compared to baseline scores. One hundred and fifty migraine patients and controls each were studied. Compared to controls, migraine patients performed significantly worse in DS-B (P < 0.0001), TMT-A (P = 0.00004), TMT-B (P < 0.0001), SW (P < 0.0001), SC (P < 0.0001), and SI (P = 0.0221). MMSE scores did not differ between patients and the controls (P = 0.3224). Compared to the patients without psychiatric comorbidity, migraine patients with psychiatric comorbidity showed no significant differences in the cognitive test scores. Significant improvement in all cognitive test scores (P < 0.001) was observed after 6 months of treatment. Migraine patients, compared to non-migraine controls, showed deficits in attention, vigilance, and executive functions during the interictal period, which improved with successful preventive treatment. Psychiatric comorbidities did not have a significant impact on cognitive dysfunctions.