The Global Burden of Disease, which is a comprehensive assessment of mortality and disability from diseases and injuries in 1990 and projected to 2020, highlights the importance of mood disorders for the world. Using the measure of disability-adjusted life years, it was determined that unipolar major depression was the fourth leading cause of disease burden in the world. It was also projected that, in the year 2020, unipolar major depression would be the second leading cause of disease burden in the world. Disabilityadjusted life years is based on both mortality and disability. If one looks at disability alone, then unipolar major depression was the leading cause of disability in the world in 1990, and bipolar disorder was the sixth leading cause. Across the world, 10.7 per cent of disability can be attributed to unipolar major depression and, in developed countries, unipolar major depression contributes to nearly 20 per cent of disease burden in women aged from 15 to 44 years. This chapter addresses bipolar disorders and depressive disorders, covering diagnostic issues, prevalence, comorbidity, use of health services, and risk factors for both types of disorder.
