Low untreated systolic blood pressure over 18 years is associated with survival free of dementia age 90.

Abstract

We hypothesized that lower untreated systolic blood pressure (SBP) would be associated with a lower risk of dementia and death up to age 95. SBP measured between 2000 and 2006 was evaluated in relationship to dementia risk and brain biomarkers from 2009-2020 (n=177) in the Gingko Evaluation of Memory Study (GEMS), mean age 95 in 2020. Participants had measurements of brain amyloid beta (Aβ) and repeat clinical-cognitive evaluations every 6 months. By 2020, only 9 of 177 patients (5%) were alive and cognitively unimpaired (CU). Mean SBP from 2000 to 2006 was 120mm Hg for nine alive/CU, 125mm Hg for alive/mild cognitive impairment (MCI), and 130mm Hg for alive/dementia (P=.03). The amount of Aβ was directly related to SBP levels. In multivariate analysis, Aβ+ in 2009 and thinner cortex were significant predictors of dementia. Excluding Aβ, SBP became a significant predictor of dementia. Low SBP untreated by antihypertensive medications was associated with significant decreased risk of dementia and less Aβ.