Hypertension and Prehypertension and Prediction of Development of Decreased Estimated GFR in the General Population: A Meta-analysis of Cohort Studies

Background: Whether blood pressure (BP) plays an independent predictive role in the onset of decreased glomerular filtration rate (GFR) remains ill-defined because existing meta-analyses have incorporated data from studies that included individuals with low GFRs at baseline. This question is critical to optimize chronic kidney disease prevention in the general population. Study Design: Systematic review and meta-analysis of longitudinal cohort studies. Setting & Population: Adults from general population. Selection Criteria for Studies: We identified in PubMed, EMBASE, and the Cochrane Library database all cohort studies evaluating the role of BP in the incidence of decreased estimated GFR (eGFR; defined as eGFR, 60 mL/min/1.73 m(2)) in individuals without decreased kidney function at baseline. Predictors: Hypertension (BP. 140/90 mm Hg), prehypertension (systolic BP of 120-139 and/or diastolic BP of 80-89 mm Hg), and BP as a continuous variable. Outcomes: Risk for decreased eGFR reported as relative risk (RR) and 95% CI. Heterogeneity (I-2) was also evaluated. Results: Data from 16 cohorts (315,321 participants) were analyzed. All studies had a Newcastle-Ottawa score in the range of 6 to 8, denoting high quality. During a mean follow-up of 6.5 years, decreased eGFR occurred in 6.6% of participants. The presence of prehypertension and hypertension increased renal risk (RRs of 1.19 [95% CI, 1.07-1.33; I-2 5 23.8%] and 1.76 [95% CI, 1.58-1.97; I-2 5 37.7%], respectively). Similarly, we found that every 10-mm Hg increase in systolic and diastolic BPs associated with higher risk for decreased eGFR (RRs of 1.08 [95% CI, 1.04-1.11; I-2 5 60.0%] and 1.12 [95% CI, 1.04-1.20; I-2 5 51.4%], respectively). Metaregression analysis showed greater risk with older age (P = 0.03), whereas other covariates were not significant. Limitations: No individual patient-level data. Conclusions: Prehypertension and hypertension, as BP levels, are independent predictors of decreased GFR in the general population, with the effect being more pronounced in the elderly. These findings are important for improving risk stratification in the general population. (C) 2016 by the National Kidney Foundation, Inc.