People who develop asthma as adults may be at greater risk of developing heart disease and having a stroke, according to new research.

“Though it’s usually not recognized as such, there are several different types of asthma, each with some unique features,” said Matthew C. Tattersall, D.O., study lead author and assistant professor of medicine at the University of Wisconsin School of Medicine and Public Health in Madison. “We looked at the type known as late-onset asthma, which tends to be more severe and more difficult to control with medicines than asthma that begins in childhood.”

Researchers followed 1,269 adults without cardiovascular disease for 14 years. Average age of asthma diagnosis in the late-onset group (beginning at age 18 or older) was 39.5 years and 8.9 years in the early-onset group.

At the beginning of the study, 111 participants had late-onset asthma and 55 had early-onset asthma. Researchers tracked cardiovascular events, including heart attack, stroke, heart failure, angina, cardiac revascularization and cardiovascular death. They accounted for cardiovascular disease risk factors that might bias results, including smoking, high blood pressure, diabetes and being overweight.

Researchers found that people with late-onset asthma were 57 percent more likely to suffer a cardiovascular event than those without asthma. Late-onset asthma sufferers were also more likely to be female (67 percent versus 44 percent) and have a higher body mass index (32.2 versus 29.4 kg/m2) than non-asthmatics. People with early-onset asthma had no difference in cardiovascular disease events compared to non-asthmatics.

Researchers speculated that differences between early-onset and late-onset asthma may help explain study findings. In addition to being harder to control, late-onset asthma is often triggered by different factors, including air pollution, and often leads to a more rapid decline in lung function. Other studies have found an association between air pollution and compromised lung function and cardiovascular disease.

“Doctors should be monitoring for high blood pressure and cholesterol closely in (late-onset asthma) patients and be aggressive in modifying any risk factors,” Tattersall said.

People with late-onset asthma can increase their chances of remaining heart-healthy and stroke-free by exercising, eating a healthy diet and maintaining a normal body weight.

The study is published in the Journal of the American Heart Association.