Plasma Renin Activity and Clinical Implication in Korean Hypertensive Patients

Suh, Soon Yong; Park, Chang Gyu; Chwe, Uk Ryol; Kim, Jin Won; Rha, Seung Woon; Seo, Hong Seok; Oh, Dong Joo; Ro, Young Moo

Abstract

BACKGROUND AND OBJECTIVES
Angiotension II, the active component in the renin angiotensin system, modulates blood pressure via vasoconstriction and sodium retention. In normal subjects, the active level of the RAS is reflected by the plasma renin activity (PRA). Importantly, when blood pressure is elevated, the level of RAS is reactively suppressed, and that of PRA approaches zero. Therefore, this study was conducted to find the characteristics of hypertensive patients according to the level of circulating renin.
SUBJECTS AND METHODS
The subjects were 275 essential hypertensive patients, with a mean age of 53.2+/-11.9 years, 9.5% of which had diabetes. Patients were classified into 3 groups: low, normal and high renin (high PRA>4.5 ng/mL/h, normal PRA: 0.75-4.5 ng/mL/h and low PRA<0.75 ng/mL/h). The relationship between the PRA and other parameters, such as plasma aldosterone, SBP, DBP, heart rate, lipid profile, body mass index (BMI) and left ventricular mass index (LVMI), were compared. The mean SBP, DBP, heart rate, lipid profile, BMI and LVMI values were compared between the 3 groups. The distribution of the PRA value was compared by sex, age, diabetes, dyslipidemia and obesity.
RESULTS
The percentages of the study population with low renin essential hypertension (LREH), normal renin essential hypertension (NREH) and high renin essential hypertension (HREH) were 47, 46 and 8%, respectively. A greater proportion of female patients showed LREH (58.6 vs. 36.1% of male), as did elderly (>55 year-old) compared to younger patients (58.7 vs. 36.2%, both p<0.001). However, there were no significant differences in the hemodynamics (SBP, DBP and heart rate), LVMI and cardiovascular risk factors (obesity, dyslipidemia and diabetes) between the 3 groups.
CONCLUSION
Women and elderly people are more likely to have LREH compare to men and younger people, who are more likely to have HREH.