Higher visit-to-visit total cholesterol variability is associated with lower cognitive function among middle-aged and elderly Chinese men

Jianian Hua,Chaofu Ke,Yueping Shen,Yanan Qiao

doi:10.1038/s41598-020-72601-7

Abstract

To examine the prospective associations between total cholesterol (TC) variability and cognitive function in a large sample of Chinese participants aged 45 years and above. A total of 6,377 people who participated in the China Health and Retirement Longitudinal Study (CHARLS) were included. TC variability was defined as the intra-individual standard deviation over two blood tests in CHARLS 2011 and 2015 (Wave 1 and Wave 3). Cognitive function was assessed by a global cognition score, which included three tests: episodic memory, figure drawing and Telephone Interview of Cognitive Status (TICS). Multivariate linear regression models (MRLMs) and generalized estimating equation (GEE) were used to investigate associations between TC variability and cognitive scores. After adjusting for potential confounders, male participants with higher visit-to-visit TC variability showed lower global cognition scores (β = − 0.71, P < 0.001). After further adjustment for baseline cognition, the association remained statistically significant (β = − 0.68, P < 0.001). The domains with declines were focused on episodic memory (β = − 0.22, P = 0.026) and TICS (β = − 0.44, P = 0.004). However, these associations were not found in women (β = − 0.10, P = 0.623). For men, the rates of decline in global cognition increased by 0.14 (β = − 0.14, P = 0.009) units per year while TC variability increased by 1 mmol/L. For males, higher visit-to-visit TC variability correlated with lower cognitive function and an increased rate of decreases in memory. More attention should be paid to cognitive decline in males with high TC variability, and particularly, on decreases in memory, calculation, attention and orientation.

Highlights

Over 90 years ago, Walter Cannon coined the term “homeostatis”[1], which hypothesized that the variability in constituents in the body is associated with abnormalities in human’s function
The mean age of the participants was 58.4 ± 8.7 years; 45.4% of the participants were male; 74% of them finished their education in primary school; and 79.7% of the participants were from rural areas
Higher total cholesterol (TC) variability was associated with higher mean TC concentrations (P < 0.001)

Summary

Introduction

Over 90 years ago, Walter Cannon coined the term “homeostatis”[1], which hypothesized that the variability in constituents in the body is associated with abnormalities in human’s function. Under the guidance of this theory, recent studies have found that increased variability in lipid levels was related to high risk of mortality, atrial fibrillation, or myocardial infarction[2,3,4,5]. Patients at high cardiovascular risk receive intensive lipidlowering therapy, leading to higher cholesterol variability. A total of 3 studies have found that cholesterol variability was associated with dementia or cognitive function[9,10,11,12]. Smit 2016 showed an association between high variability in low density lipoprotein (LDL) levels and low cognitive function. We used a national representative database, the China Health and Retirement Longitudinal Study (CHARLS), to investigate cognitive function among people with high variability in cholesterol levels

Methods

Results

Conclusion