Abstract 350: Renal Dysfunction Associated With Incident Hypertension According to Blood Pressure Categories in a Non-hypertensive Population in the Suita Study: An Urban Cohort Study
Background and purpose: No studies have examined the influence of decreased glomerular filtration rate (GFR) on incident hypertension (HT) according to blood pressure (BP) categories among a healthy cohort. We assessed the relationships between renal dysfunction and incident HT according to BP categories in a Japanese urban cohort.
Methods: A total of 4,751 participants (30 to 79 years old without HT at baseline) in the Suita Study were prospectively followed up for incident HT. BP categories were defined by the ESH-ESC in 2007 criteria from an every 2 years health examination by well-trained physicians. Systolic and diastolic BPs (SBP and DBP, respectively) were taken as the average of the 2nd and 3rd measurements. Chronic kidney disease (CKD) was defined as GFR <60 mL/min/1.73 m2, which was estimated using the MDRD equation modified by the Japanese coefficient. Urinary protein was determined by using a dipstick method. Urinary protein results of "+-" or more grade were defined as proteinuria. The Hazard ratios (HRs) and 95% confidence intervals (CIs) of incident HT associated with CKD and proteinuria were calculated by using the Cox proportional hazard models adjusted for age, sex, diabetes, dyslipidemia, body mass index, exercise, smoking, and excessive drinking.
Results: During the 7.2 years of mean follow-up, 21, 63, and 137 cases of incident HT per 1000 person-years were observed in the optimal, normal, and high-normal BP (HNBP) categories, respectively. The adjusted HRs (95% CIs) for incident HT were 1.2 (1.1-1.5) in the CKD group, compared with the non-CKD group. The HRs (95% CIs) were 1.2 (1.1-1.4) and 1.7 (1.4-2.1) in the urinary protein "+-" and "1+" or more groups, respectively. The HRs (95% CIs) of the non-CKD and proteinuria, CKD and non-proteinuria, and CKD and proteinuria groups were 1.5 (1.2-2.0), 0.9 (0.6-1.3), and 1.8 (1.0-3.1) in the normal BP and 1.3 (1.1-1.6), 1.3 (1.0-1.8), and 1.8 (1.2-2.6) in the HNBP categories, respectively, compared with the same BP categories of the non-CKD and non-proteinuria group.
Conclusions: CKD and urinary protein are risk factors for incident HT in the non-hypertensive population. This study emphasizes the importance of urinary protein in prehypertension for the primary prevention of HT, even if they have non-CKD.
- © 2012 by American Heart Association, Inc.