Nutritional status mediates the relationship between depression and mild cognitive impairment among Chinese community-dwelling older adults.

BACKGROUND

Mild cognitive impairment (MCI) and depression are prominent public health concerns among older adults, closely linked to their nutritional status. Our study aimed to explore the association and mediation pathways involving depression, nutritional status, and MCI in this population.

METHODS

The study included 4799 community-dwelling Chinese older adults aged 60 years and older in Tianjin and Shanghai, China. We utilized the 30-item Geriatric Depression Scale (GDS-30) to assess depression presence and severity. A GDS-30 score ≥11 indicated the presence of depression. Participants were categorized by symptom severity: "None" (GDS-30<11), "Mild" (11≤GDS-30 ≤ 20), "Moderate to severe" (20<GDS-30 ≤ 30). Nutritional status was evaluated using the Mini Nutritional Assessment-Short Form (MNA-SF). Cognitive function was assessed with the Mini-Mental State Examination (MMSE), and daily living activities were measured using the Instrumental Activities of Daily Living (IADL). Logistic regression and mediation analyses were conducted with full adjustment for potential confounding factors.

RESULTS

Among 4799 older adults (2010 men, mean age 71.5 ± 5.8 years), 11.8% exhibited depression, and 12.1% had MCI, while 18.8% were at risk of malnutrition, and 1% were malnourished. Participants at risk of malnutrition or experiencing depression were associated with MCI. Additionally, nutritional status significantly mediated the relationship between depression and cognitive function, with a slightly larger mediating effect, particularly in cases of mild depression.

CONCLUSIONS

Individuals at risk of malnutrition or depressed were associated with MCI. Poor nutritional condition mediates the association between depression and MCI in older adults. Early nutritional interventions may mitigate cognitive decline in depressed older adults.