Doctors are warning heart attack patients about their diet and lifestyle, but their advice is falling on deaf ears, a new study has found.

People are now more aware than ever of the risk factors for heart disease, but it doesn’t appear to be resonating with those who need to follow the advice most, according to an American College of Cardiology statement.

The study found that patients who had had a heart attack continued to ignore doctor advice and resume smoking, eating poorly, or doing other things that result in high blood pressure or even diabetes — and the rates of people doing that have actually increased.

The study indicates that there is a lot of work to be done at preventing heart attacks rather than merely focus on treating them. Doctors will need to figure out ways to encourage their patients to adopt a better lifestyle during routine checkups, researchers say.

The study involved 4,000 patients who were treated for a heart attack known as ST-elevation myocardial infarction (STEMI) between 1995 and 2014. A STEMI heart attack is the most deadly, and happens when a coronary artery is mostly blocked.

Those who smoke, don’t exercise, and eat an unhealthy diet are most at risk of STEMI heart attacks. But unfortunately, the study showed that prevention methods weren’t working: the number of patients who had three or more major risk factors for a STEMI heart attack rose from 65 to 85 percent over that time period.

“On the whole, the medical community has done an outstanding job of improving treatments for heart disease, but this study shows that we have to do better on the prevention side,” Samir Kapadia, M.D., professor of medicine and section head for interventional cardiology at Cleveland Clinic and the study’s primary investigator, said in the statement. “When people come for routine checkups, it is critical to stress the importance of reducing risk factors through weight reduction, eating a healthy diet and being physically active.”