In a US national survey, the risk of heart attack was increased fourfold among young adults who had used cocaine more than 10 times in their lifetimes, report researchers from the Beth Israel Deaconess Medical Center in Boston.

In this nationally representative population, roughly 10 percent of the heart attacks in those aged 18 to 45 years were associated with a history of more than 10 lifetime episodes of cocaine use, Dr. Murray A. Mittleman and his colleagues report in the American Journal of Cardiology.

Recognition of this association between cocaine use and heart attack led the American Heart Association to issue a scientific statement earlier this year urging doctors to consider cocaine use in young adults with unusual cardiovascular or lung complaints.

The new findings stem from a look at data from the Third National Health and Nutrition Examination Survey, or NHANES III, conducted from 1988 to 1994. Among the nearly 12,000 participants aged 18 to 59 years in NHANES III, approximately 4.6 percent reported using cocaine more than 10 times.

According to Mittleman and colleagues, the prevalence of heart attack among these subjects was roughly 3 times higher than among subjects who never used cocaine.

For the 9,000 subjects aged 18 to 45 years, the risk of heart attack was roughly fourfold higher among the 5.7 percent who were frequent cocaine users.

This is concerning, the investigators say, given that cocaine use has increased from 14 percent in those aged 18 to 59 years in the NHANES III data to 19 percent in those aged 20 to 59 in the most recent NHANES survey conducted between 2005 and 2006.

SOURCE: American Journal of Cardiology, October 15, 2008.