Dementia, including AD and VaD, is the most common neurological disease in older adults, whereas headaches are the most common neurological disorder across all ages. The relationship between these two conditions is, however, not yet well understood. Previous studies investigating a potential association were mainly done in patient populations and yielded varying conclusions.
The purpose of the study by Morton et al. was to see if migraines are a risk factor for dementia and its subtypes, AD and VaD, in a population-based cohort. A total of 679 community-dwelling participants of 65 and older from the Canadian Manitoba Study of Health and Aging were included in the analysis. All were cognitively intact and had complete information on migraine history and all covariates at baseline, and were assessed for all-cause dementia, AD, and VaD five years later (follow-up).
At follow-up, 7.5% of participants had developed dementia (all-cause), 5.1% had developed AD, and 1.9% had developed VaD. After adjustment for confounding (age and education) and intervening (stroke) variables, people with all-cause dementia were almost three times more likely to have a history of migraines than those with intact cognition (odd ratio [OR] 2.97). AD was significantly associated with a history of migraines, also after adjusting for age and education (OR 4.22). Analysis did not show a significant association between VaD and migraines, despite the vascular mechanisms involved in the physiology of migraine.
Based on these results, the authors conclude that migraines are a significant risk factor for AD and all-cause dementia. Identifying such risk factors enables earlier detection of at-risk people and contributes to better understanding of how AD and all-case dementia develop, which in turn might prove to be useful for development of new preventive treatments.