# Association of lifestyle, dietary pattern, and liver function with cognition in older adults: findings from a cross-sectional study

## TL;DR

This study finds that poor liver function and unhealthy lifestyle are linked to cognitive decline in older adults, emphasizing the importance of liver health for brain function.

## Contribution

The study reveals combined effects of lifestyle, diet, and liver function on cognitive impairment in older adults.

## Key findings

- Poor liver function, indicated by elevated AST/HDL-C, increases mild cognitive impairment risk.
- A healthy dietary score positively correlates with better cognitive test scores.
- AST/HDL-C and ALT/HDL-C have cut-off values indicating increased MCI risk.

## Abstract

Single lifestyle, dietary pattern, and liver function are closely associated with cognitive ability, yet their combined influences on cognition remain unclear. This study aimed to investigate the effects of lifestyle, dietary patterns, and liver function on cognitive impairment among older adults.

One thousand and ninety-six older adults were recruited from communities. Among them, 630 participants completed cognitive function tests. The lifestyle and dietary patterns of the participants were assessed using a healthy lifestyle score (HLS) and a healthy dietary score (HDS). Liver function was assessed using four predictive indicators: AST/HDL-C, ALT/HDL-C, HSI, and ZJU. Cognitive function was measured using the Montreal Cognitive Assessment (MoCA). Logistic regression, receiver operating characteristic curves (ROC), and restricted cubic splines (RCS) were applied to explore the relationship between variables.

A significant negative correlation was observed between HLS and liver function indicators (rAST/HDL-C = −0.156, rZJU = −0.270, both p < 0.001), whereas a significant positive correlation was identified between HDS and MoCA scores (r = 0.074, p < 0.05). Poor liver function, represented by elevated plasma AST/HDL-C, was associated with increased mild cognitive impairment (MCI) risk (OR = 1.029, p = 0.007). ROC analysis showed that plasma AST/HDL-C had the highest predictive power for MCI (AUC = 0.634). RCS analysis revealed that AST/HDL-C and ALT/HDL-C were positively correlated with the risk of MCI, with cut-off values of 14.1 and 10.1, respectively.

Impaired liver function is strongly associated with cognitive impairment, highlighting the critical role of maintaining healthy liver function in preventing MCI in the elderly. A healthy lifestyle positively correlated with both liver and cognitive functions, and a balanced diet significantly improved cognitive outcomes.