Indeed, patients treated with pravastatin for 5 years during the trial gained an average of 5 extra years free of nonfatal MI or cardiovascular death at the 20-year mark, he said.
“The average age of the men was 55 years during the trial and 20 years on they’re now 75 years old. This covers the entire period of premature cardiovascular morbidity and mortality. We would argue that this is a good picture of the lifetime benefit, which is different from lifetime risk. This is real events happening to real people, not predictions,” observed Dr. Packard, professor of cardiovascular and medical sciences at the University of Glasgow, Scotland.
The group given pravastatin for 5 years collectively spent 24,038 days in the hospital for any cardiovascular event, compared with 30,342 days for controls.
Particularly noteworthy was the divergence in the risk of heart failure, with 96 cases being diagnosed during 20 years in patients who received 5 years of pravastatin, compared with 128 in controls.
“Heart failure was our biggest surprise,” he said. “We got no result for heart failure at all at 5 years; these were middle-aged men with just high cholesterol, so we didn’t see much in the way of incident heart failure. But extrapolating 20 years, there is a 31% risk reduction in the incidence of hospitalization for heart failure in the statin-treated group, compared to the placebo-treated group. This is a remarkable finding.”
For WOSCOPS participants who got a 20% drop in LDL during 5 years of pravastatin from a baseline of 190 mg/dL, as was typical, the number of patients who needed to be treated (NNT) for 5 years to prevent one cardiovascular hospital admission over a 20-year period was six. Moreover, for every 10 patients on statin therapy for 5 years, an average of 19 hospital days were avoided over the course of 20 years. For patients with a baseline LDL of 120 mg/dL, the NNT was 10, and 12 hospital days were saved over a 20-year period for every 10 patients treated for 5 years.
“This is a real savings to the health service and the health care providers to offset the cost of drugs,” Dr. Packard continued.
He urged physicians to look beyond the initial reports of primary outcomes of the statin clinical trials and take a long-term view.
“If you take a lifetime approach to benefit so you’re looking not only at the first event, but the second event, the third, at heart failure, and at death, you can see tremendous benefits, whereas usually we only focus on the first event. And that’s not the full cost evaluation that you need to do,” according to Dr. Packard.
The overall incidence of cancer during 20 years of follow-up was 24.8% in the initial placebo arm and 24.5% in the pravastatin group, with no differences between the two groups in any type of cancer. Nor did the original pravastatin group show any increase in noncardiovascular mortality.