Exclusion of Older Adults and Women from Recent Trials of Acute Coronary Syndromes

OBJECTIVES: To determine whether the participation of older adults and women in published clinical trials has increased during recent years. DESIGN: Systematic review to identify clinical trials of acute coronary syndromes (ACSs) published from May 2007 to May 2009. Trials were excluded if they enrolled fewer than 50 participants, were substudies of previously published trials, or initiated treatment more than 3 weeks after the acute cardiac event. SETTING: A search of MEDLINE and the Cochrane Central Register of Controlled Trials. PARTICIPANTS: Sixty-eight thousand sixteen participants of 80 trials. MEASUREMENTS: Information on the age of trial participants, percentage of participants who were female, and whether there were specific exclusions based on age were abstracted from all included trials. RESULTS: Twenty-three trials (29.7%) had explicit exclusion criteria based on age. Only 13.8% of study participants were aged 75 and older, and 27.7% were women. These percentages are below the representation of all U.S. adults experiencing an ACS in recent years who were aged 75 and older (41.9%) or female (41.5%). The average age of all study participants was 61.6 ± 3.8. There was a significant association between the mean age of a study population and the proportion of women enrolled in the trial. CONCLUSION: Older adults and women remain underrepresented in recent clinical trials of people hospitalized with an ACS. These exclusions may hinder efforts to inform evidence-based clinical decision-making in these high-risk populations.