Robert Wood Johnson Foundation Clinical Scholars at the University of Michigan say as the number of seniors grows, the need for research to improve health and healthcare for seniors is growing as well.
The study, published online in the Journal of General Internal Medicine, says as of 2009, adults age 65 and older represent 12.5 percent of the U.S. population -- about one in every eight Americans -- and by 2030, that number is expected to almost double, but this group accounts for 34 percent of personal healthcare expenditures.
Lead author Dr. Donna Zulman says the review of clinical trials found that one in five trials excluded patients based on their age alone. Furthermore, almost half of the remaining trials excluded people using criteria that could disproportionately affect older adults, such as physical frailty or impaired cognition.
The study found that trials rarely assess how treatments affect function and quality of life.
"It is rarely appropriate to exclude people from clinical trials based on their age alone," study co-author Dr. Jeremy B. Sussman says. "This is especially true in trials investigating conditions that are common in older adults."
The researchers suggest clinical trial evidence for older adults would be improved by eliminating upper age limits for study inclusion.