Abstract:
Objective To examine the association between depressive symptoms and cognitive function and the influences of gender, region of life, and residential area on the association in middle-aged and elderly people in China.
Methods Data on 17 705, 2 834, and 574 individuals aged ≥ 45 years were extracted from the 2011, 2013, and 2015 China Health and Retirement Longitudinal Study (CHARLS) enrollment surveys, which used the 10-item Center for the Epidemiological Studies of Depression Short Form (CES-D-10) to identify participants′ depression symptoms. Multiple linear stepwise regression was used to analyze the factors influencing cognitive function and to compare the differences in the influence of depressive symptoms on cognitive function across gender, regions of life, and residential areas.
Results The final analysis included 14 979 participants with a mean age of 58.05 ± 9.35 years and 51.18% (7 661) males. For all participants, the mean cognitive function score was 12.09 ± 3.54, and 33.3% (4 985) were classified as having depressive symptoms. The results of multiple linear stepwise regression showed that being female (B = – 0.31), being older (B60 – 69 years = – 0.19; B70 – 79 years = – 1.18; B80 – 89 years = – 2.12; B ≥ 90 years = – 3.66), living in central and western regions (Bcentral = – 0.36; Bwestern = – 0.57), smoking (B = – 0.15), and having depressive symptoms (Bmild to moderate = – 0.90; Bsevere = – 1.51) were risk factors for cognitive decline; further stratified analysis revealed that depressive symptoms had a significant negative impact on cognitive function in middle-aged and older adults across gender, residential area, and region of life, with higher levels of depression associated with poorer cognitive function.
Conclusion The prevalence of depressive symptoms is high and cognitive function is poor among middle-aged and elderly people in China. Depressive symptoms have a negative predictive effect on cognitive function, and the effect of depressive symptoms on cognitive function shows no significant differences among genders, living regions, and residential areas.