Body mass index, fat free mass, uric acid, and renal function as blood pressure levels determinants in young adults

Aim: We assessed some major determinants of blood pressure (BP) in young adulthood to plan a lifestyle changes policy Methods: A cross sectional survey was held, involving 2373 high school people (age 18-21), measuring BP, body mass index (BMI), waist circumference (WCirc), fat free mass (FFM); alcohol and smoking habits were evaluated by a questionnaire. In a subset of this population (n= 60) uric acid (UA), estimated glomerular filtration rate (eGFR) were also evaluated. Results: Smoking and not alcohol was correlated to systolic blood pressure (SBP) through quartiles (31.7%, 39.1%, 46.5%, 45.5%). Systolic BP was significantly correlated with FFM in the whole population (r = 0.51) as well as in SBP quartiles (r = 0.243, 0.138, 0.118, 0.204). FFM-SBP cluster analysis gave two centroids corresponding to sexes; females n= 998; coordinates (116.4 mmHg, 38.9 kg) and males n= 1068; coordinates (131.3 mmHg, 56.7 kg). In the n= 60 substudy a multiple linear regression model (multiple R = 0.741) with SBP as dependent variable and UA, FFM, BMI, eGFR as explicative ones, only UA (beta coefficent = 0.363, partial r = 0.240, P < 0.01) was the determinant of BP particularly in men. Moreover in the same group we found an inverse relationship between eGFR (albeit always in the normal range) and UA, as well as for women (r = -0.54, P < 0.01) and men (r = -0.43, P < 0.01) analyzed separately. Conclusions: A significant correlation exists between BP and FFM; UA has proven to be the most important SBP determinant. At variance with paediatric age UA was negatively correlated with renal function. Dietary intervention on UA and alcohol habits in young adults seems advisable to prevent hypertension.