Assessing the impact of classical risk factors on myocardial infarction by rate advancement periods.

The risk or rate advancement period (RAP) proposed by Brenner et al. (Epidemiology 1993;4:229-36) conveys information on the impact of a risk factor on the age dimension of chronic disease occurrence and may thus facilitate communication of epidemiologic findings. The RAP expresses how much sooner a given risk or rate of disease occurrence is reached among exposed than among unexposed individuals. The purpose of the present analysis was to derive estimates of RAPs for cardiovascular risk factors in relation to incident nonfatal and fatal myocardial infarction in middle-aged men of the Monitoring Trends and Determinants in Cardiovascular Diseases (MONICA) Augsburg cohort, Germany, between 1984 and 1995. RAPs were estimated based on Cox proportional hazards models. After multivariate adjustment, hypertension, smoking, and dyslipidemia were associated with RAPs of 8, 11, and 11 years, respectively, conditional on infarction-free survival to baseline and absence of competing risks. The RAP may be interpreted as that, on average, smokers are expected to advance their risk of myocardial infarction approximately 11 years compared with never/former smokers; for example, 50-year-old smokers are expected to carry the same risk of infarction as 61-year-old nonsmokers. The authors encourage the use and evaluation of the RAP as an effective risk communication tool in actual counseling situations.