Depression is a leading cause of disability and is projected to become the second highest burden of disease (measured in disability-adjusted life years) by the year 2020. The authors of this study examined prevalence of depression from 2000 to 2006 in the adult Danish population. Specifically they looked at major depressive disorder (MDD) as well as the distribution across the whole Major Depression Inventory (MDI) scale. In addition, they looked at the trend in major depressive disorder across different socioeconomic groups. A random sample of 4759 Danes in their forties and fifties were followed in a longitudinal study based on postal questionnaires answered in 2000 and 2006. The prevalence of major depressive disorder increased from 2.0% to 4.9% during the years 2000 to 2006. The increasing prevalence was more pronounced in women in their forties and with lower socioeconomic status. The study concluded that major depressive disorder as well as mental health in general was of public health concern.

Andersen I, Thielen K, Bech P, Nygaard E, Diderichsen F: Increasing prevalence of depression from 2000 to 2006. Scand J Public Health. 2011 Sep 29. [Epub ahead of print].

http://www.ncbi.nlm.nih.gov/pubmed/21965477