Life’s Simple 7 cardiovascular risk score and rate of cognitive decline in preclinical dementia

Abstract Background We investigated whether vascular risk factors (VRFs), assessed with the Life’s Simple 7 (LS7) score, are associated with rate of cognitive decline in the preclinical dementia phase. We sought to test whether (1) poor LS7 further accelerates rate of cognitive decline in preclinical dementia or (2) the dementia process itself overshadows potential effects of LS7. Method This population‐based study included 1,449 participants aged ≥ 60 years (M = 69.99, SD = 9.25) from the Swedish National Study on Aging and Care‐Kungsholmen (SNAC‐K). Participants aged < 78 years at baseline (M = 65.03) were categorised into a young‐old group and those ≥ 78 years (M = 82.61) into an old‐old group. An extensive cognitive test battery (episodic memory, semantic memory, verbal fluency, and perceptual speed) was administered across 12 years. VRFs were assessed with the Life’s Simple 7 (LS7) score at baseline and included four behavioral (smoking, diet, physical activity, and body mass index) and three biological (plasma glucose, total serum cholesterol, and blood pressure) metrics. Participants were categorised into having poor or intermediate/optimal cardiovascular health. Preclinical dementia was defined as being dementia‐free at baseline and diagnosed with dementia (DSM‐IV criteria) at one of the follow‐up assessments. Level and change in cognitive performance as a function of LS7 categories and future dementia status were determined using linear mixed‐effects models. Result Participants in a preclinical dementia phase were more likely to have a poorer LS7 score initially compared to those who remained dementia‐free (p = 0.023). For young‐old individuals, poor diet was associated with an accelerated perceptual speed decline (β = ‐0.05, 95% CI ‐0.08 to ‐0.02) and a poor plasma glucose score was associated with faster rates of verbal fluency (β = ‐0.019, ‐0.09 to ‐0.01) and global cognitive (β = ‐0.028, ‐0.06 to 0.00) decline in preclinical dementia. Conclusion The association between VRFs and cognitive decline was most pronounced in young‐old individuals in a preclinical phase of dementia and driven mostly by diet and plasma glucose. Poor cardiovascular health may be associated with further acceleration of cognitive decline in preclinical dementia.