The prevalence of mental disorders in older people in Western countries - a meta-analysis.

OBJECTIVE: To conduct a meta-analysis assessing the prevalence of mental disorders in older people in Europe and North America.

METHOD: Studies that reported prevalence rates of mental disorders in older people from the general population were identified through MEDLINE, PsycINFO, Web of Science, and reference lists for the period between January 2000 and December 2011. Studies were included if they reported prevalence rates of mental disorders in older people (50+ years) from the community. The final sample comprised 25 studies. Prevalence rates were extracted, and effect sizes were transformed into logits. Random-effects models were calculated due to significant heterogeneity. In meta-regression analyses possible sources of bias, including age of onset, gender distribution, and risk of bias were examined. To analyze the robustness of the results, sensitivity analyses were performed. Publication bias was assessed with funnel plots and the Egger method.

RESULTS: Disorders with the highest prevalence estimates were dimensional depression (19.47%), lifetime major depression (16.52%), and lifetime alcohol use disorders (11.71%). Disorders with the lowest estimates were current and lifetime drug use disorders (0.34% and 0.19%, respectively), and current bipolar disorder and current agoraphobia (both 0.53%).

CONCLUSION: The majority of studies investigated major depression, panic disorder and social phobia. Future research requires a larger database on the epidemiology of mental disorders in the elderly. Furthermore, an improvement to the methodology that addresses the challenges of older age and produces comparable data, including the use of instruments tailored to the needs of older people, is required.