Researchers have identified coronary heart disease (CHD) risk factors, and studies have shown that these risk factors may help estimate a patient’s risk of CHD. Some researchers have proposed replacing this risk-factor–based approach with universal prophylactic administration of a “polypill” that contains medications known to reduce CHD risk in all patients older than 55 years. They purport that this method would benefit adults in this age group who have elevated levels of CHD risk factors as well as the much greater number with borderline levels. Vasan and colleagues assessed the relative contribution of borderline and elevated risk factors to CHD events.
The authors applied data from the Framingham Heart Study and the Framingham Offspring Study to the estimated number of at-risk persons from the Third National Health and Nutrition Examination Survey (NHANES III). Participants from the Framingham studies were eligible for the Vasan and colleagues study if they were between 35 and 74 years of age at baseline and had no history of CHD. Participants included 3,418 men and 3,973 women. Risk factors were defined as optimal, borderline, or elevated based on current national guidelines. For example, current smoking was considered elevated, previous smoking was borderline, and no smoking was optimal. Researchers performed an identical risk-factor assessment for a comparable group of participants from NHANES III. A statistical analysis was performed using data on 10-year CHD event rates from the Framingham Study and predicted CHD events (based on the distribution of risk factors in NHANES III participants).
Although 26 percent of men and 41 percent of women in the NHANES III sample had at least one borderline CHD risk factor but no elevated risk factors, they accounted for only 8 percent of predicted CHD events. In comparison, 25 percent of CHD events occurred in participants with one elevated risk factor, and more than two thirds occurred in persons with one or two elevated risk factors. Although the 10-year risk of CHD events increased with age, 17 percent of events in men and 9.7 percent of events in women were predicted to occur in the youngest age group studied (35 to 44 years of age).
The authors conclude that their results support current recommendations to treat patients with elevated CHD risk factors. They also conclude that the association of borderline risk-factor levels to CHD events was significantly weaker than that of elevated risk factor levels, which casts doubt on the effectiveness of the “polypill” strategy. The authors note that two thirds of men and one third of women 35 to 44 years of age had at least one modifiable elevated CHD risk factor. Therefore, they suggest targeting this group for early intervention.