An inexpensive combination of a cholesterol-lowering drug and one to reduce blood pressure can reduce the incidence of heart attacks and strokes by as much as 60 percent, but prompting patients to begin the regimen and then to stay on it is an extremely difficult task, researchers say.
Giving the drugs to nearly 70,000 people with cardiovascular disease or diabetes prevented an estimated 1,271 heart attacks and strokes in one year, Dr. James Dudl of the Kaiser Permanente Care Management Institute and his colleagues report in the American Journal of Managed Care.
The inspiration for the study came from the Archimedes Model, a sophisticated computer simulation of the human body that predicted that lowering blood pressure and cholesterol simultaneously in those at the highest risk for cardiovascular problems could reduce the incidence by 71 percent. But such a study had never been carried out in humans before.
The Kaiser team chose two generic drugs, cholesterol-lowering lovastatin and blood pressure-reducing lisinopril, and offered them to 170,000 members of their managed care programmes in Northern and Southern California who suffered from heart disease or diabetes.
Some of the patients were already taking one of the drugs, but none of those selected was taking both. About 75 percent were also taking aspirin, but the researchers did not include aspirin in the protocol because they had no way to monitor usage.
They began the program in 2004, and nearly 70,000 patients agreed to participate. The team monitored compliance for two years by checking on whether and how often patients refilled their prescriptions, then monitored health effects in the third year through the patients' health records. Some 47,268 patients had what the team termed "low exposure" to the drugs, taking them less than half the time. Their risk of hospitalization for heart attack or stroke was lowered by 15 events per 1,000 person-years, and an estimated 726 events were prevented. An additional 21,292 patients had "high exposure" to the drugs, taking them more than half the time. Their risk was reduced by 26 events per 1,000 person-years, preventing an estimated 545 events. "What was fairly amazing to me was that we got such a good drop in heart attack and strokes despite the low adherence," Dudl says. "The issue now is how to increase adherence.'' The primary reasons for non-adherence, he notes, were things such as, "I don't know why I was taking the drugs," "I forgot to refill the prescription," and "I worry about side effects." Those are issues "that have to be addressed with each patient, one by one." Kaiser now has a follow-up program focused on adherence, he says. "We made it the simplest regimen we could," he adds, with a standardised dose of each drug for everyone. "Can you imagine how difficult it would have been if it were a more complicated regimen or physicians had to schedule multiple visits to adjust dosages for each patient. It's a great example of how difficult it is for people to understand and do something that is beneficial to them."