Exclusion of elderly persons from health-risk behavior clinical trials

It has been found that the elderly population is underrepresented in clinical trials aimed at disease treatment. It is unknown to what extent this group is also excluded from clinical trials aimed at reducing health-risk behaviors.

We systematically reviewed clinical trials targeting the leading health-risk behaviors, as identified by Healthy People 2010: tobacco use, overweight/obesity, physical inactivity, substance abuse, and irresponsible sexual behavior. Using MEDLINE, we identified clinical trials published in the five most cited medical journals between January 1990 and May 2004.

The majority (53%) of the 198 health-risk behavior clinical trials excluded persons over the age of 65; the exclusion percentage increased to 72% for those over the age of 75. The exclusion of elderly persons in these five medical journals did not decline over the 14 years studied. This age exclusion pattern was not explained by the intervention's intrusiveness or whether illness was an exclusion criterion. The trials that included those over the age of 65 were more likely to report a significant finding in the predicted direction.

Although elderly persons are most at risk for diseases linked to lifestyle behavior, such as heart disease, they were excluded from the majority of health-risk behavior clinical trials in five major medical journals.