# A network analysis of sleep quality, cognitive function, and depressive symptoms among community-dwelling older adults

## TL;DR

This study explores how sleep quality, depression, and cognitive function are interconnected in older adults, identifying key symptoms that link these factors.

## Contribution

The study introduces a network analysis approach to identify bridge symptoms linking sleep, depression, and cognition in older adults.

## Key findings

- Subjective sleep quality is the core symptom in the network of sleep, depression, and cognition.
- Depressive symptoms (GDS) act as the strongest bridge between cognitive and sleep symptoms.
- Attention and calculation, along with registration, are strongly connected within cognitive symptoms.

## Abstract

Many countries, including China, are facing rapid population aging issues. Among middle-aged and older adults, depressive symptoms and sleep disturbances are associated with cognitive impairment. Therefore, this study aimed to examine the relationships between sleep, depression, and cognitive function in older adults.

We recruited 457 elderly people aged over 60 years from the Matang community of Wuhu to participate in this cross-sectional study. We utilized the Mini-Mental State Examination (MMSE), Pittsburgh Sleep Quality Index (PSQI), and Geriatric Depression Scale (GDS) to measure our participants, with 126 individuals completing all of them. We used the collected data for network analysis to identify the bridge symptoms in the MMSE-PSQI-GDS network by calculating bridge centrality.

The core symptom of the MMSE, GDS, and PSQI networks was subjective sleep quality (SSQ). The bridge symptoms in MMSE, GDS, and PSQI were “GDS” and “OR” (orientation). Among the symptoms, “GDS” had the highest bridge centrality. The edge connecting nodes habitual sleep efficiency (HSE) and used sleep medication (USM) had the strongest weight (0.67) around all the symptoms of PSQI. Nodes attention and calculation (AC) and registration (RG) had the strongest weight (0.48), connecting all MMSE symptoms.

This study highlights the central role of subjective sleep quality and the bridging role of depression in the interconnected network of cognition, sleep, and mood among older adults. These findings suggest that interventions targeting sleep quality and depressive symptoms may have broad benefits for cognitive function and mental health. By identifying key symptom interactions, this network-based approach provides guidance for prioritizing assessment and intervention strategies in the geriatric population.