Age, Sex Representation Still Low In Cardiovascular Research

Elderly people and women remain under-represented relative to their disease prevalence in randomized, controlled cardiovascular trials.

Their exclusion continues despite efforts to include both groups in research.

North American researchers comment: “Despite growing awareness in the last decade of potential age and sex biases, there has been only limited improvement in the inclusion of elderly people and women among cardiovascular randomised controlled trials, as evidenced in the published literature.

“More than half of all recently published trials still failed to enroll any patients aged 75 years or older, and women were consistently enrolled at half of their prevalence in the affected population.

“Given that treatment risks and benefits may alter as a function of patient sex and (more particularly) age, regulatory agencies will need to continue to monitor enrolment patterns to ensure that future trials are tested in representative populations.

“Agencies that fund clinical studies also should provide additional resources to promote enrolment of representative patient populations.

“These efforts are urgently needed if we are to provide evidence-based care to all cardiac patients.”

Researchers from Duke University Medical Centre in Durham, North Carolina did a search of the literature from January 1966 to March 2000 to determine whether age and sex representation in cardiovascular research had improved.

They also reviewed how these enrolments compare with disease prevalence.

They included English-language, randomized, controlled trials of acute coronary syndrome patients. They excluded trials with 50 or fewer patients and those without clinical end points.

A total of 7,645 studies were identified. Researchers reviewed 593 of these.

Investigators report: “The number of published randomized, controlled trials with explicit age exclusions has declined from 58 percent during 1966 to 1990 to 40 percent during 1990 to 2000.

“Trial enrolment of patients aged 75 years or older increased from 2 percent of studies published in 1966 to 1990 to 9 percent during 1990 to 2000, but remains well below their representation among all patients with myocardial infarction (37 percent) in the United States.

“Enrolment of women has risen from 20 percent for studies published between 1966 and 1990 to 25 percent during 1990 to 2000, but remains well below their proportion of all patients with myocardial infarction (43 percent) in the US.”

JAMA, 2001; 286: 708-713.