Lower Blood Pressure, Small-Vessel Disease, and Apathy in Older Persons With Mild Cognitive Deficits

Abstract

BACKGROUND: In older persons, both high and low blood pressure (BP) levels are associated with symptoms of apathy. Population characteristics, such as burden of cerebral small-vessel disease (CSVD), may underlie these apparently contradictory findings. We aimed to explore, in older persons, whether the burden of CSVD affects the association between BP and apathy. DESIGN: Cross-sectional study. SETTING: Primary care setting, the Netherlands. PARTICIPANTS: Community-dwelling older persons (mean age = 80.7 years; SD = 4.1 years) with mild cognitive deficits and using antihypertensive treatment, participating in the baseline measurement of the magnetic resonance imaging substudy (n = 210) of the Discontinuation of Antihypertensive Treatment in the Elderly Study Leiden. MEASUREMENTS: During home visits, BP was measured in a standardized way and apathy was assessed with the Apathy Scale (range = 0-42). Stratified linear regression analyses were performed according to the burden of CSVD. A higher burden of CSVD was defined as 2 or more points on a compound CSVD score (range = 0-3 points), defined as presence of white matter hyperintensities (greater than median), any lacunar infarct, and/or two or more microbleeds. RESULTS: In the entire population, those with a lower systolic and those with a lower diastolic BP had more symptoms of apathy (β = −.35 [P =.01] and β = −.66 [P =.02], respectively). In older persons with a higher burden of CSVD (n = 50 [24%]), both lower systolic BP (β = −.64, P =.02) and lower diastolic BP (β = −1.6, P =.01) were associated with more symptoms of apathy, whereas no significant association was found between BP and symptoms of apathy in older persons with a lower burden of CSVD (n = 160). CONCLUSIONS: Particularly in older persons with a higher burden of CSVD, lower BP was associated with more symptoms of apathy. Adequate BP levels for optimal psychological functioning may vary across older populations with a different burden of CSVD. J Am Geriatr Soc 68:1811-1817, 2020.