Longitudinal associations between blood pressure and dementia in the very old

Abstract

Background/aims: Midlife hypertension is associated with an increased risk for dementia, but the association between blood pressure and dementia in very old age is unclear.

Methods: In a population-based cohort study, a total of 102 individuals aged 85, 90 or ≥ 95 years participated in 2 examinations with a 5-year interval. The investigations consisted of a structured interview, blood pressure measurement, rating scales such as the Mini-Mental State Examination (MMSE) and an investigation of medical charts.

Results: The majority of participants exhibited a decline in blood pressure. Baseline systolic blood pressure (SBP), diastolic blood pressure or pulse pressure (PP) were not associated with incident dementia or with decline in MMSE scores in multiple regression analyses adjusted for age and sex. However, incident dementia cases exhibited a greater decline in SBP (p = 0.02) and PP (p = 0.04), and decline in SBP was associated with a decline in MMSE score (p = 0.008).

Conclusion: In this small longitudinal study on the very old, no association between baseline blood pressure and incident dementia was found, but individuals who developed dementia exhibited a greater blood pressure decline. Low blood pressure could be an effect of dementia in the very old.