Association of comorbid depressive and anxiety symptoms with cognitive impairment and dementia in Chinese elderly people.

BACKGROUND

Cognitive impairment is a globally prevalent public health disorder following rapid population aging. Although depression can trigger cognitive decline, few studies have focused on how anxiety and its comorbidity with depression can affect cognitive decline development.

METHODS

Cognitive impairment was recognized based on the Mini-Mental State Examination (MMSE), while dementia was diagnosed with self-/proxy-reported evaluations. The 10-item Center for Epidemiologic Studies Depression Scale (CESD-10) and the 7-item Generalized Anxiety Disorder Scale (GAD-7) were employed for evaluating depressive and anxiety symptoms. The impact of comorbidity on cognitive outcomes was assessed with logistic and linear regression models.

RESULTS

The study involved 13,792 adults (age ≥ 65 years; mean age: 84.2 ± 11.5 years) from the Chinese Longitudinal Healthy Longevity Survey. Among them, comorbid depressive and anxiety symptoms occurred in 7.7% of older adults. Prevalence was 9.2% for cognitive impairment and 1.4% for dementia. Compared to individuals with only depressive or anxiety symptoms, those with both symptoms exhibited a higher probability of developing cognitive impairment (adjusted OR: 2.07, 95% CI: 1.44, 2.97) and dementia (adjusted OR: 2.55, 95% CI: 1.39, 4.69), with adults aged ≥ 80 years exhibiting a stronger association. Additionally, women, particularly the oldest-old, were at a higher risk of comorbidity-associated dementia. We also observed an identical correlation for MMSE scores, where psychiatric comorbidity correlated significantly with lower scores. The interaction between individual characteristics and depression and anxiety showed no significant effects on cognitive impairment or dementia.

CONCLUSIONS

Comorbidity of depression and anxiety shows an association with dementia and cognitive impairment in Chinese older adults, particularly in oldest-old individuals. Early screening and interventions targeting psychiatric comorbidity may delay dementia progression in this population. CLINICAL TRIAL NUMBER : Not applicable.