Longitudinal association of hypertension and dyslipidemia with cognitive function in community-dwelling older adults: the SONIC study

Abstract

The associations among cognitive function, hypertension, and dyslipidemia in older adults are controversial. Therefore, we investigated the associations among cognitive decline, hypertension, dyslipidemia, and their combination in community-dwelling older people in their 70s, 80s, and 90s in the long-term observational Septuagenarians, Octogenarians, Nonagenarians, Investigation with Centenarians (SONIC) study. We administered the Montreal Cognitive Assessment Japanese version (MoCA-J) by trained geriatricians and psychologists, and conducted blood testing and blood pressure (BP) measuring by medical staff involving 1186 participants. We performed multiple regression analysis to assess the relationships among hypertension, dyslipidemia, their combination, and lipid and BP levels with cognitive function at the 3-year follow-up after adjusting for covariate factors. At the baseline, the percentage of the combination of hypertension and dyslipidemia was 46.6% (n = 553), hypertension was 25.6% (n = 304), dyslipidemia was 15.0% (n = 178), and that without hypertension or dyslipidemia was 12.7% (n = 151). Conducting multiple regression analysis, no significant correlation was found between the combination of hypertension and dyslipidemia and MoCA-J score. In the group with the combination, high high-density lipoprotein cholesterol (HDL) levels resulted in higher MoCA-J scores at the follow-up (β = 0.06; P < 0.05) and high diastolic BP (DBP) also resulted in higher MoCA-J scores (β = 0.08; P < 0.05). The results suggest that high HDL and DBP levels of individuals with HT & DL and high SBP levels of individuals with HT were associated with cognitive function in community-dwelling older adults.

Associations between hypertension and cognitive, mood, and behavioral parameters in very old adults: results from the IlSIRENTE study

“…Our findings are partially supported by other studies that reported inverse associations between BP levels and cognitive function in very old adults. Nakamura et al ( 6 ) found that high BP was a predictor of better global cognitive function 3 years later in a cohort of very old Japanese adults. Similar results were reported by Corrada et al ( 7 ) and Chen et al ( 26 ) after examining North American and Japanese older adults aged 90 years and older, respectively.…”

“…A possible explanation for these findings is that high BP might be a compensatory mechanism to maintain adequate cerebral perfusion in the face of vascular detriments caused by aging ( 6–9 ). Indeed, the old vessel is commonly characterized by losses in structural integrity and function, which involves significant impairment of endothelium dilation, resulting in reduced blood flow to major tissues, including the brain ( 28–30 ).…”

“…As a matter of fact, many studies have found that the progression of hypertension is associated with cognitive decline and the occurrence of mild cognitive impairment (MCI) and dementia, including Alzheimer’s disease (AD) ( 3–5 ). However, these results are conflicting, given that other investigations found that high BP levels might be a protective mechanism, mainly in very old adults, to counteract the deleterious effects of aging on cerebrovascular structure ( 6–9 ).…”

How should we manage hypertension and dyslipidemia to maintain cognitive function in older adults?

“…The present study by Nakamura et al [1] is valuable for understanding the associations among cognitive decline, hypertension, and dyslipidemia in older adults. The Septuagenarians, Octogenarians, Nonagenarians, Investigation with Centenarians (SONIC) study provides important insights into these complex relationships.…”