Multimorbidity is significantly associated with higher prevalence of depressive symptoms in middle-aged and older Chinese adults.

Objective: Chronic diseases and depressive symptoms are prevalent global health concerns. This study examined the association between multimorbidity and depressive symptoms in the middle-aged and older adults. Methods: This cross-sectional study used data from the China Health and Retirement Longitudinal Study (CHARLS, China, 2011-2020), including 18,551 adults aged ≥45 years. Depressive symptoms were assessed with the 10-item Center for Epidemiologic Studies Depression Scale (score ≥10). We analyzed associations for each chronic disease and for their coexistence. Results: After adjusting for sociodemographic and lifestyle factors, chronic liver disease, cardiovascular disease, chronic kidney disease, and diabetes were significantly associated with depressive symptoms. Participants with ≥2 of these conditions had higher odds of depressive symptoms (OR = 2.34, 95 % CI: 1.89, 2.89). Subgroup analyses showed consistent associations within strata. In age-stratified analyses, adjusted ORs were 2.96 for participants <60 years and 2.26 for those ≥60 years. In sex-stratified analyses, adjusted ORs were 2.26 for females and 2.70 for males. In body mass index analyses (BMI), adjusted ORs were 3.60 for <24 kg/m2 and 1.88 for ≥24 kg/m2. Conclusions: Multimorbidity was significantly associated with depressive symptoms among Chinese adults aged ≥45 years. These associations were consistent in sex, age, and BMI.