Fatima Rodriguez, MD, MPH reviewing
Strongest predictors of survival were not smoking, routine physical activity, blood pressure control, and a healthy diet.
Control of cardiovascular risk factors through aggressive pharmacotherapy and lifestyle interventions is the backbone for treating stable ischemic heart disease (SIHD). These investigators tested the hypothesis that the greater number of risk-factor goals achieved, the better the long-term survival, in an analysis of observational follow-up data from the COURAGE trial, which randomized patients to receive optimal medical therapy (OMT) with or without percutaneous coronary intervention (NEJM JW Cardiol May 2007 and N Engl J Med 2007; 356:1503). Control of risk factors was defined as follows:
- LDL <85 mg/dL (My comment:this would equal 2.2 in the SI units used in Canada. It may be hard to achieve this without taking a statin drug but note that low LDL is less important than the other changes listed.)
- Systolic blood pressure <130 mm Hg
- Body-mass index <25 kg/m2 or if >27.5 kg/m2, ≥10% weight loss
- Not smoking
- >150 minutes weekly of moderate physical activity
- American Heart Association Step 2 diet
Among 2102 study participants with complete risk factor ascertainment 1 year after randomization, there were 473 deaths at a mean follow-up of 6.8 years. There was a graded relationship between the number of risk factors controlled and survival (16% decrease in risk of death for each additional goal achieved). The strongest predictors of survival were not smoking, routine physical activity, blood pressure control, and a healthy diet.
The finding that risk factor control was highly predictive of survival, even in a secondary-prevention population with SIHD, is especially noteworthy because COURAGE overall failed to show a mortality benefit for percutaneous coronary intervention (my comment: percutaneous coronary intervention = stenting a narrowed site in one of the arteries that feed the heart) on top of optimal medical therapy. Taken together, these findings emphasize the importance of addressing and promoting lifestyle interventions beyond pharmacotherapy.