Association of Sasang Constitutional Types with Incident Hypertension: A 12-Year Follow-Up Study

Abstract

Objectives: Sasang constitutional types (SCTs) are four distinct classifications of people based on physiologic and physical characteristics. The different types have been reported to have different disease susceptibility, but there are no studies reporting the association of SCT and hypertension (HTN) over a long-term follow-up period. This study prospectively investigated the association between SCT and incidence of HTN. Design: This was a prospective study in a population-based cohort study in Korea. Subjects: Data from two independent population-based cohorts that are embedded within the Korean Genome and Epidemiology Study were used. A total of 2083 subjects who were free of HTN at baseline were selected for the analysis. Outcome measures: HTN was diagnosed as systolic blood pressure (BP) >= 140 mmHg and diastolic BP >= 90 mmHg, use of antihypertensive medication, or diagnosis by doctor. The SCTs were classified using an integrated diagnostic method that included facial features, body shape, voice, and questionnaire responses. The association between the SCT and the incidence of HTN was investigated by Cox proportional hazard regression analysis and calculation of estimated survival functions. Results: The Tae-eum (TE) type showed a significantly increased risk for HTN (hazard ratio [HR] = 1.55, 95% confidence interval [CI] 1.15-2.10; p = 0.005), even after adjusting for all possible confounders. In a stratified analysis by body mass index (BMI) conducted only in the TE type, even those in the TE type with normal BMI had a significantly higher risk for HTN (HR = 1.47, 95% CI 1.07-2.03; p = 0.016). Furthermore, survival analysis showed that the TE type had a higher rate of developing HTN than the So-eum and So-yang types had, regardless of obesity status. Conclusions: These results show that the TE type is an independent risk factor for HTN. Thus, early prevention and treatment for HTN in this type are needed.