Disability associated with mental disorders in metropolitan China: an application of the quantile regression approach.

Recently active mental disorders are associated with substantial disability, but there is little research on residual disability once symptoms have subsided. The aim of this study is to estimate the degree to which recent disability might be due to recent or past history of mental disorders using a quantile regressions (QR) model that makes it possible to study the full range of disability. Data were from cross-sectional surveys of Chinese living in Beijing and Shanghai, China (n=1628). The World Health Organization Disability Assessment Schedule and the WHO Composite International Diagnostic Interview were used to assess recent disability and common mental disorders, respectively. Recently active mental disorders are found to be associated with elevated levels of disability, especially for current substance use disorder. Anxiety disorders stand out with high levels of disability. Individuals at the higher disability levels show large variations in their disability levels. These epidemiological estimates from China add to the evidence based on the global burden of neuropsychiatric disorders, quantifying the hypothesized influence of recently active and past disorders with the novel QR approach. In future studies, we hope to complete more detailed studies of the causal role of mental disorders in the development of disability.