Associations of ischemic heart disease with dementia and cognitive decline in older adults: Results from a 12‐year population‐based cohort study

Abstract

AbstractBackgroundIschemic heart disease (IHD) is a leading cause of death worldwide and a potential risk factor for dementia. However, the association of IHD with dementia and cognitive decline in old age has not been extensively addressed in population‐based cohorts. Furthermore, the extent to which the potential association of IHD with cognitive decline might be attributable to common complications of IHD, such as heart failure (HF) and atrial fibrillation (AF), remains unclear. The objective of this study is to investigate the longitudinal association of IHD with dementia and cognitive decline, and to clarify the role of HF and AF.MethodWe analysed data from 2615 dementia‐free participants in the population‐based Swedish National study on Aging and Care in Kungsholmen (age ≥ 60years, female 62%). Participants were regularly followed from 2001‐2004 (baseline) through 2013‐2016. IHD, HF, and AF cases until baseline were identified through patient registers, physical and instrumental examinations, and interviews by physicians. Dementia was diagnosed according to the DSM‐IV criteria. Global cognitive function was assessed with a neuropsychological test battery.The associations of IHD with incident dementia and cognitive decline were investigated using Cox proportional hazard models and linear mixed‐effects models, respectively. The models were controlled for age, sex, education, smoking, alcohol consumption, physical activity, vascular risk factors, and concomitant cardiovasulcar diseases (AF, HF, and stroke). Furthermore, we performed the stratified analysis by the presence of AF or HF.ResultDuring the 12‐year follow‐up period, 400 participants (15%) developed dementia. The multi‐adusted hazard ratio (HR) of dementia associated with prevalent IHD was 1.34 (95% CI: 1.03, 1.75) compared to those without IHD. This association remained significant in IHD without prevalent AF or HF at baseline. Similarly, prevalent IHD was associated with an average annual change in global cognitive z‐score of ‐0.02 (95% CI: ‐0.03, ‐0.01). The associations remained significant after excluding individuals with AF and HF. There was no statistical interaction of IHD with age, sex, or APOE genotype on risk of dementia and cognitive decline.ConclusionIHD is a risk factor for dementia and cognitive decline in the general older population independent of HF and AF.