Clinical trials of potential antidepressants: to what extent are the elderly represented: a review

Background There is widespread use of antidepressants in the elderly population. The principle of treatment of depression, however, is derived mostly from studies employing young adults and healthy elderly. This article reviews the literature on the extent to which the elderly are represented in clinical trials of potential antidepressants. Method Medline search of relevant articles of clinical trials of potential antidepressants. Results The maximum age of inclusion for most clinical trials was 65 years. The highest age reported for depressed subjects was 90 years. There was no clear consensus on who were considered to be elderly; clinical trials conducted on the elderly included subjects who were 50, 55, or 60 years and over. Pharmacological studies on healthy subjects were most often done on young adults, age range 18 to 65 years. The period of study was relatively shorter for clinical trials done on elderly subjects. There was however, no difference in the exclusion or inclusion criteria between studies done in young and elderly subjects. Conclusions Elderly subjects aged 75 years and over were clearly underrepresented in the clinical trials of potential antidepressants. For drugs that are used by the elderly, in its pivotal studies for registration, the inclusion of at least 25% of subjects aged 75 years and over is recommended. Copyright © 2005 John Wiley & Sons, Ltd.