Prevalence of depressive disorders in the elderly

Community-based mental health studies have revealed that the point prevalence of depressive disorders in the elderly population of the world varies between 10% and 20%, depending on cultural situations. A retrospective study based on analysis of various study reports was conducted, to determine the median prevalence rates of depressive disorders in the elderly population of India and various other countries in the world. All the studies that constituted the sample were conducted between 1955 and 2005. Included are only community-based, cross-sectional surveys and some prospective studies that had not excluded depression at baseline. These studies were conducted on a homogenous community of the elderly population in the world, who were selected by a simple random sampling technique. After applying the inclusion and exclusion criteria on published and indexed articles, 74 original research studies that surveyed a total of 487,275 elderly individuals, in the age group of 60 years and above, residing in various parts of the world, were included for the final analysis. The median prevalence rate and its corresponding interquartile range were calculated. The chi-square test and chi-square for linear trend were applied. A P value of