Blood pressure indexes and end-stage renal disease risk in adults with chronic kidney disease

Abstract

Background: Few studies have compared different blood pressure (BP) indexes for end-stage renal disease (ESRD) risk among individuals with chronic kidney disease.

Methods: We examined the relationship between systolic BP (SBP), diastolic BP (DBP), pulse pressure (PP) and mean arterial pressure (MAP) and ESRD risk among 2,772 participants with an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m(2) calculated using the Chronic Kidney Disease Epidemiology Collaboration equation in the REasons for the Geographic And Racial Differences in Stroke (REGARDS) study. BP was measured during a baseline study visit between January 2003 and October 2007 with ESRD incidence through August 2009 ascertained via linkage with the United States Renal Data System (n = 138 ESRD cases).

Results: The mean age was 72.1(standard deviation: 8.7) years. After multivariable adjustment for socio-demographic and clinical risk factors including antihypertensive medication use, the hazard ratio (HR) for ESRD associated with one standard deviation higher SBP (18 mm Hg) was 1.67, (95% confidence intervals (CI) 1.43-1.96), DBP (11 mm Hg) was 1.38, (95% CI 1.16-1.63), PP (15 mm Hg) was 1.50, (95% CI 1.27-1.78) and MAP (11 mm Hg) was 1.54, (95% CI 1.32-1.79). Higher levels of SBP remained associated with an increased HR for ESRD after additional adjustment for DBP (1.65, 95% CI: 1.35-2.01), PP (1.73, 95% CI: 1.32-2.26), and MAP (1.61, 95% CI: 1.16-2.23). After adjustment for SBP, the other BP indexes were not significantly associated with incident ESRD.

Conclusions: These data suggest that of several blood pressure indexes including DBP, PP and MAP, SBP may have the strongest association with ESRD incidence among individuals with reduced eGFR.

Figure 1

Multivariable adjusted hazard ratios for end-stage renal disease associated with systolic blood pressure, diastolic blood pressure, pulse pressure, and mean arterial pressure. Black line represents the hazard ratio, gray area is the 95% confidence interval. Bars represent the percentage of the population. Hazard ratios are adjusted for age, race, sex, geographic region of residence, current smoking, physical activity, income, waist circumference, highsensitivity C-reactive protein, history of cardiovascular disease, diabetes, high-density lipoprotein-cholesterol, antihypertensive medication use, and estimated glomerular filtration rate.

Figure 2

Hazard ratios for developing end-stage renal disease associated with one standard deviation higher systolic blood pressure (18 mm Hg) in subgroups of REasons for the Geographic and Racial Differences in Stroke (REGARDS) study participants with an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m². Hazard ratios (HRs) are adjusted for age, race, sex, geographic region of residence, current smoking, physical activity, income, waist circumference, high-sensitivity C-reactive protein, history of cardiovascular disease, diabetes, high-density lipoprotein-cholesterol, antihypertensive medication use, and estimated glomerular filtration rate.