P.15 Isolated Systolic Hypertension and Central Blood Pressure: Implications from the National Nutrition and Health Survey in Taiwan

Abstract

Objectives

We aimed to investigate the association between isolated systolic hypertension (ISH) and central blood pressure (BP) in a nationally representative population.

Methods

A total of 2029 adults without anti-hypertensive medicine, aged ≥19 years old participated in the 2013–2016 National Nutrition and Health Survey in Taiwan. Central and brachial BP were simultaneously measured using a cuff-based stand-alone central BP monitor purporting to measure invasive central BP (type II device). Central hypertension [1] was defined by central systolic (SBP)/diastolic BP (DBP) ≥130 or 90 mmHg, and ISH was defined by brachial SBP ≥140 and DBP <90 mmHg.

Results

The prevalence of ISH was 6.51% among adults aged ≥19 years old (2.15% [n = 21] for young adults [aged <50 years] and 10.54% [n = 111] for older adults [aged ≥50 years]). ISH subjects had significantly higher central pulse pressure (PP) (62.8 mmHg for the young and 72.4 mmHg for elders) than those subjects with either isolated diastolic hypertension (brachial SBP <140 and DBP ≥90 mmHg, central PP 44.8 mmHg) or systolic diastolic hypertension (brachial SBP ≥140 and DBP ≥90 mmHg, central PP 60.2 mmHg). There was a U-shaped trend in the association between age and ISH prevalence, and between age and central PP. The ISH prevalence was 2.95%, 1.73% and 10.54%, and the average central PP was 49.5, 47.0, and 54.0 mmHg for subjects aged <30, between 30–50, and ≥50 years, respectively. Moreover, all ISH adults had central hypertension and a higher prevalence of obesity than the normotensives (body mass index ≥27 Kg/m², 71% vs. 17%, for age <50 years, and 27% vs. 17% for age ≥50 years).

Conclusions

All subjects with ISH, young or older, had central hypertension. Central PP was higher in the young and older age groups in comparison to the middle age group. The U-shaped trend corresponded to the association between age and ISH prevalence.