A risk score for predicting near-term incidence of hypertension: The Framingham Heart Study

Background: Studies suggest that targeting high-risk, nonhypertensive individuals for treatment may delay hypertension onset, thereby possibly mitigating vascular complications. Risk stratification may facilitate cost-effective approaches to management. Objective: To develop a simple risk score for predicting hypertension incidence by using measures readily obtained in the physician's office. Design: Longitudinal cohort study. Setting: Framingham Heart Study, Framingham, Massachusetts. Patients: 1717 nonhypertensive white individuals 20 to 69 years of age (mean age, 42 years; 54% women), without diabetes and with both parents in the original cohort of the Framingham Heart Study, contributed 5814 person-examinations. Measurements: Scores were developed for predicting the 1-, 2- and 4-year risk for new-onset hypertension, and performance characteristics of the prediction algorithm were assessed by using calibration and discrimination measures. Parental hypertension was ascertained from examinations of the original cohort of the Framingham Heart Study. Results: During follow-up (median time over all person-examinations, 3.8 years), 796 persons (52% women) developed new-onset hypertension. In multivariable analyses, age, sex, systolic and diastolic blood pressure, body mass index, parental hypertension, and cigarette smoking were significant predictors of hypertension. According to the risk score based on these factors, the 4-year risk for incident hypertension was classified as low (<5%) in 34% of participants, medium (5% to 10%) in 19%, and high (>10%) in 47%. The c-statistic for the prediction model was 0.788, and calibration was very good. Limitations: The risk score findings may not be generalizable to persons of nonwhite race or ethnicity or to persons with diabetes. The risk score algorithm has not been validated in an independent cohort and is based on single measurements of risk factors and blood pressure. Conclusion: The hypertension risk prediction score can be used to estimate an individual's absolute risk for hypertension on short-term follow-up, and it represents a simple, office-based tool that may facilitate management of high-risk individuals with prehypertension.