Background:
Orthostatic hypotension (OH) has been associated with incident cardiovascular disease and all-cause mortality, but few studies have examined long-term associations with cognitive decline and dementia
Hypothesis:
OH will be associated with greater cognitive decline and risk of incident dementia
Methods:
We prospectively analyzed 11503 participants who attended visit 1 (1987-1989) of the ARIC study and had no history of coronary heart disease or stroke. OH was defined as a drop in systolic blood pressure (BP) >=20 mmHg or a drop in diastolic BP >=10 mmHg upon standing from a supine position. Dementia was ascertained using cohort surveillance, telephone contact with the participant or their proxy, or a comprehensive cognitive and neurologic exam in 2011-2013. Cognition was measured via three neuropsychological tests administered in 1990-1992, 1996-1998, and 2011-2013 that were summarized using a Z score. We used adjusted Cox regression and linear mixed models.
Results:
At visit 1 (mean age 54 years, 57% female, 27% black) 6% of participants had OH. In adjusted models, persons with OH at baseline were 40% more likely to develop dementia than those without OH (HR: 1.40, 95%CI: 1.13, 1.73; Table). Associations were significantly larger in persons with hypertension (p-value for interaction=0.023). Persons with OH compared to those without had significantly more cognitive decline over 20 years (difference: -0.12, 95% CI: -0.23, -0.02; Table).
Conclusions:
OH assessed in midlife was independently associated with incident dementia and cognitive decline over 20 years. Although typically considered a transient mechanism, these data suggest that OH, or the underlying disease conditions manifesting as OH, persist over time. Whether OH is a marker of vulnerability beyond that of standard hypertension measures, or whether repeated transient exposure to hypotension reduces perfusion to the brain sufficiently to lead to long-term cerebral dysfunction is an important area for further research.
Association of orthostatic hypotension with incident dementia, stroke, and cognitive decline
