Evaluating the Framingham Hypertension Risk Prediction Model in Young Adults : The Coronary Artery Risk Development in Young Adults (CARDIA) Study

Abstract

A prediction model was developed in the Framingham Heart Study (FHS) to evaluate the short-term risk of hypertension. Our goal was to determine the predictive ability of the FHS hypertension model in a cohort of young adults advancing into middle age and compare it with the predictive ability of prehypertension and individual components of the FHS model. We studied 4388 participants, aged 18 to 30 years without hypertension at baseline, enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) Study, who participated in 2 consecutive examinations occurring 5 years apart between the baseline (1985-1986) and year 25 examination (2010-2011). Weibull regression was used to assess the association of the FHS model overall, individual components of the FHS model, and prehypertension with incident hypertension. During the 25-year follow-up period, 1179 participants developed incident hypertension. The FHS hypertension model (c-index=0.84; 95% confidence interval, 0.83-0.85) performed well in discriminating those who did and did not develop hypertension and was better than prehypertension alone (c-index=0.71; 95% confidence interval, 0.70-0.73). The predicted risk from the FHS hypertension model was systematically lower than the observed hypertension incidence initially (χ(2)=249.4; P<0.001) but demonstrated a good fit after recalibration (χ(2)=14.6; P=0.067). In summary, the FHS model performed better than prehypertension and may be a useful tool for identifying young adults with a high risk for developing hypertension.