Background: Both mental and physical disorders can result in role limitation, such as ‘days out of role’, which have an important impact on national productivity losses. This paper analyses data from the South African Stress and Health Study (SASH) on the association of both mental and physical disorders with days out of role. Methods: Face-to-face interviews were conducted with a representative sample of 4,351 adult South Africans. The World Health Organization’s Composite International Diagnostic Interview (WHO-CIDI) was used to assess the presence of 21 mental and physical disorders that were grouped into 10 disorder categories for the analysis: major depressive disorder, any anxiety disorders, any substance abuse disorders, headaches or migraine, arthritis, chronic pain, cardiovascular, respiratory, diabetes and digestive disorders. Multiple regression techniques were used to explore associations between individual disorders, comorbid conditions, and annual days spent out of role. The estimated societal effects of the disorders [population attributable risk proportion (PARP)] were obtained. Results: The majority of respondents who reported a mental or physical disorder also reported another disorder (62.98 %). The average number of disorders reported by respondents who had at least one disorder was 2.3. Overall 12.4 % of respondents reported any days out of role due to mental or physical disorder. Anxiety disorders and depression were associated with highest days out of role (28.2 and 27.2, respectively) followed closely by arthritis and pain (24.7 and 21.7, respectively). Any mental disorder was associated with 23.6 days out of role, while any physical disorder was associated with 15.5 days out of role. Of the mental disorders, anxiety disorders had the highest PARP in relation to days out of role (9.0 %) followed by depression (4.8 %) and substance disorder (3.3. %). More than one-third (37.6 %) of days out of role are attributable to physical disorders and 16.1 % to mental disorders. Conclusions: Comorbidity is common in both mental and physical disorders, and both are associated with substantial days out of role in South Africa. These data indicate substantial social and economic loss associated with these conditions, and emphasize the need to integrate health services to include common mental disorders in all basic packages of care and to assess for and manage comorbid conditions.

SM is supported by a postdoctoral fellowship awarded by the Faculty of Health Sciences (FHS), University of Cape Town. CL is supported by a grant from the Department for International Development (DFID