Family history of hypertension may have a stronger association with the incidence of hypertension than previously estimated: the SBS study.

A family history (FH) of hypertension is associated with an increased risk of new-onset hypertension. However, the risk of FH estimated in normotensives using conventional methods may have been somewhat underestimated by excluding early-onset cases, who are highly likely to have FH of hypertension. This large-scale longitudinal study on a middle-aged population (mean age: 46.8 years) revealed that the hazard ratio of FH of hypertension for the development of hypertension was higher when calculated for the entire study population (N = 34,792), including hypertensives at baseline by treating them as left-censored cases, using an interval-censored Cox proportional hazards model (1.73, 95% confidence interval: 1.67-1.79, P < 0.001) than that calculated in normotensives (n = 28,271) using a conventional Cox model (1.35, 95% confidence interval: 1.28-1.44, P < 0.001). The effect of changes in the possible confounders during the follow-up period was negligible. Thus, the risk of FH of hypertension for the development of hypertension may be higher than previously reported.