The association of depressive symptoms with disability among adults in China

Background: The symptoms that patients with major depressive disorder (MDD) experience are the dominant contributing factors to its heavy disease burden. This study sought to identify key symptoms leading to disability in patients with MDD. Methods: Subjects consisted of patients who had a 12-month MDD diagnosis based on the China Mental Health Survey (CMHS). World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) was used to assess the degree of disability. The associations between depressive symptoms and disability were analyzed using a linear regression and logistic regression with a complex sampling design. Results: Of the 32,552 community residents, 655 patients were diagnosed with 12-month MDD. The disability rate due to MDD was 1.06% (95% CI: 0.85%-1.28%) among adults in Chinese community and 50.7% (95% CI: 44.3%-57.1%) among MDD patients. Depression was associated with all functional losses measured by the WHODAS. Feelings of worthlessness in life or inappropriate guilt, and psychomotor agitation or retardation were the key symptoms related to disability. Economic status, co-morbidity of physical diseases or anxiety disorders were correlates of disability scores. Limitations: The disability rate might be underestimated due to the exclusion of MDD patients living in hospitals. The effect of treatments on disability was excluded. Conclusions: Psychological symptoms, not somatic symptoms, contribute to disability in MDD patients. Disability worsens when physical diseases or anxiety disorders are present. More attention could be paid to psychological symptoms, physical diseases, and anxiety disorders in MDD patients with disabilities.