Drugs May Prolong Life After Heart Attack

For heart attack survivors, it really is important to follow doctor's orders: A Canadian study shows you may be less likely to die if you continue taking your medicine - as prescribed.

The study of 31,455 heart attack survivors found 24 percent of the patients worst about continuing their medicine died over the course of the study, compared to 16 percent of those best at taking their medication.

The patients, who were 66 and older, were followed for 2.4 years, on average, after their heart attack.

They had prescriptions for at least one of the following types of heart drugs: statins, beta-blockers, or calcium channel blockers.

Researchers, including the University of Toronto's David Alter, MD, PhD, FRCPC, studied how long the patients continued refilling their prescriptions. Their report appears in The Journal of the American Medical Association.

About the Drugs

All of the patients survived at least one year and three months after their heart attack.

Most took their drugs faithfully for the first year. But adherence fell later on.

One of the types of drugs prescribed, statins, cuts cholesterol and includes such drugs as Crestor, Lipitor, Pravachol, and Zocor.

Beta-blockers include such drugs as Coreg and Toprol-XL. They help the heart relax and slow heart rate, boosting the heart's pumping ability over time.

Calcium-channel blockers include Norvasc, Plendil, and Cardizem. They treat chest pain (angina) and high blood pressure.

Of the Canadian patients, 57 percent filled a prescription for a statin, 77 percent filled a prescription for a beta-blocker, and 30 percent for a calcium-channel blocker within three months after hospital discharge for their heart attack. (Some took more than one type of drug.)

Pharmacy Use

Among those with statin prescriptions, 13 percent had stopped taking their statins by the time the study ended. A fifth of those with beta-blocker prescriptions quit taking their beta-blockers. A third of those with calcium-channel blocker prescriptions had stopped taking those drugs.

It's not clear why the patients stopped taking the drugs, which were free under the Canadian health care system.

Better Adherence, Longer Lives

About 14,300 patients stuck with their statin prescriptions for at least 80 percent of the days studied. Those patients had the lowest death rate—16 percent—during the study.

An additional 2,407 patients followed their prescriptions for 40 percent to 79 percent of the days studied. They had the second-lowest death rate: 20 percent.

The highest death rate occurred in the patients with the lowest drug adherence.

Those patients took their drugs for less than 40% of the days studied. Nearly a quarter of them—24 percent—died during the course of the study.

Survival Rate by Drug

People who kept taking their statin drugs had the best survival rates, followed by those taking beta-blockers.

Calcium-channel blockers weren't associated with longer (or shorter) lives.

The study doesn't prove the drugs alone saved the patients' lives. For instance, the researchers didn't look at exercise habits, diet, or smoking status.

But they did adjust for many factors, including the patients' age and other health problems.

Moral of the story? It's important to follow prescriptions carefully. And if you have concerns about a drug you're taking, talk with your doctor before quitting the drug or making changes.

SOURCES: Rasmussen, J. The Journal of the American Medical Association, Jan. 10, 2007; vol 297: pp 177-186. WebMD Medical Reference provided in collaboration with The Cleveland Clinic: "High Cholesterol: Cholesterol-Lowering Medication." WebMD Medical Reference provided in collaboration with The Cleveland Clinic: "Heart Failure: Treatment With Beta Blocker Medication." WebMD Medical Reference provided in collaboration with The Cleveland Clinic: "Heart Failure: Calcium Channel lockers." News release, JAMA/Archives.