Does optimal cardiovascular health protect against cognitive decline in aging?: Epidemiology / Risk and protective factors in MCI and dementia

Background The presence of cardiovascular risk factors leads to negative consequences in old age. To promote the intervention of such risk factors, the American Heart Association defined a metric of ideal cardiovascular health, also referred to as Life’s Simple 7 (LS7). The adherence to the LS7 recommendations has previously been linked to a lower risk of dementia and cognitive decline. The objective of this study was to investigate the association between individual and composite cardiovascular health metrics and rate of cognitive decline in an older population‐based sample. Method Participants aged ≥60 years from the Swedish National Study on Aging and Care‐Kungsholmen underwent repeated neuropsychological testing across 12 years. Domain specific scores were calculated for episodic memory, semantic memory, verbal fluency, and processing speed. The LS7 score, assessed at baseline, was composed of four behavioral (smoking, body mass index, diet, and physical activity) and three biological (serum total cholesterol, plasma glucose, and blood pressure) metrics. All metrics were categorized into three levels (poor = 0, intermediate = 1, and optimal = 2), where the LS7 total score was the sum of seven metrics (range 0‐14). On the basis of tertiles, it was categorized into poor (scores 0‐6), intermediate (7‐9) and optimal (10‐14). Data were analyzed with linear mixed‐effects models. Result Among 1828 participants with data on LS7 (mean age 70.4; 60.8% women), nobody achieved optimal levels for all 7 metrics. The average total score was 7.7 (SD = 1.9) and participants were classified as having poor (26.3%), intermediate (55.6%), or optimal (18.2%) cardiovascular health. People belonging to the intermediate or optimal group of cardiovascular health showed higher levels of cognitive performance. Although a more ideal level on specific metrics (e.g. blood pressure) was significantly associated with slower rates of cognitive decline, we observed no significant associations of the composite cardiovascular health metric with rate of cognitive change. Conclusion In this cohort study, a composite score of cardiovascular health (LS7) did not predict rate of cognitive decline. Ideal cardiovascular health in specific metrics, however, was associated with slower decline rates. Further analyses of subgroups and interaction effects are ongoing.