A new study has found that older men with higher testosterone levels are more likely to have a heart attack or other cardiovascular disease in the future.

Researchers studied nearly 700 men, aged 65 and older. After giving all of the participants blood tests to determine their testosterone levels, researchers divided the men into four groups based on their hormone levels to observe trends in rates of coronary heart disease events.

During an average follow-up of four years, they found that higher total testosterone level related to an increased risk of coronary disease. In particular, men whose total testosterone was in the highest quartile had more than double the risk of coronary disease compared with men in the lowest quartile.

"Many in the general public are using testosterone supplements for various medical problems, including low sex drive and mood disorders, which are not life-threatening," said the study’s author Kristen Sueoka, M.D., a resident physician at the University of California, San Francisco. "These men may unknowingly be placing themselves at higher risk for cardiovascular disease."