Adult Mental Disorders
Authors: Steven Hyman, Pamela Collins, Rachana Parikh, Vikram Patel
This chapter focuses on the four leading contributors to adult mental illness globally—schizophrenia, bipolar disorder, depressive disorders, and anxiety disorders—selected because of their high contribution to the global disease burden, accounting for 66 percent of disability-adjusted life years (DALYs) lost and 69 percent of years lived with disability (YLDs) due to mental and behavioral disorders. The combination of high prevalence, early onset, a clinical course that is either chronic or remitting and relapsing, and impairment of critical brain functions makes mental disorders a major contributor to the global disease burden. The greatest segment of the burden results from YLDs, particularly for ages 15–49 years, a critical life interval for completing education, starting a family, and increasing work productivity. The etiologies of mental disorders involve interactions among genetic, developmental, social, and environmental risk factors. Collaborative care treatment models can effectively deliver evidence-based packages, but the treatment gap for mental disorders remains significant around the world.