“Strict” blood pressure control and progression of renal disease in hypertensive nephrosclerosis

Abstract

Hypertensive nephrosclerosis is a progressive renal disease and the leading cause of end-stage renal disease (ESRD) in blacks in the United States. It is generally believed that hypertensive renal injury is responsible for progressive renal failure; however, it is not known whether pharmacologic lowering of blood pressure to any level prevents progression of renal disease. Accordingly, we performed a long-term prospective randomized trial to determine whether "strict" [diastolic blood pressure (DBP) 65 to 80 mm Hg] versus "conventional" (DBP 85 to 95 mm Hg) blood pressure control is associated with a slower rate of decline in glomerular filtration rate. Eighty-seven non-diabetic patients (age 25 to 73; 68 black, 58 male) with long-standing hypertension (DBP > or = 95 mm Hg), chronic renal insufficiency (GFR < or = 70 m/min/1.73 m2) and a normal urine sediment were studied. DBP was pharmacologically lowered to < or = 80 mm Hg (3 of 4 consecutive measurements at 1 to 4 weeks intervals) after which patients were randomized. DBP and GFR (renal clearance of 125I-iothalamate) were measured at baseline, at three months and every six months post-randomization. The rate of decline in GFR (GFR slope, in ml/min/1.73 m2/year), estimated by the method of maximum likelihood in a mixed effects model, was the primary outcome variable. In a secondary analysis, 50% reduction in GFR (or a doubling of serum creatinine) from baseline, ESRD and death were combined.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of intensive blood pressure lowering on the progression of chronic kidney disease: a systematic review and meta-analysis

“…These trials involved a total of 9287 participants with chronic kidney disease (Table 1). 13,14,17,18,[21][22][23][24][25][26][27][28] Because kidney failure typically develops slowly over time, we included the long-term post-trial follow-up data from the African American Study of Kidney Disease and Hypertension (AASK; 8.8-12.2-yr follow-up) 13 and MDRD trials (16.7-yr followup), although the blood pressure differences between the 2 arms were not significant during the cohort phase in these 2 studies. The reported trial quality varied substantially.…”

“…Four of the 11 trials did not describe allocation concealment, 17,18,21,28 and another 3 did not describe whether the analysis was done by intention-to-treat [23][24][25] 28 and 4 studies had diastolic blood pres sure targets below 75-80 mm Hg with comparators ranging from 80 to 90 mm Hg. 21,[23][24][25] A trial involving pediatric patients targeted a 24-hour mean blood pressure below the 50th percentile, compared with the 50th to 95th percentiles in the control group. 18 Two trials had more liberal targets for intensive treatment (< 140-150 mm Hg systolic and 85 mm Hg diastolic).…”

Blood Pressure, Proteinuria, and Phosphate as Risk Factors for Progressive Kidney Disease: A Hypothesis

“…12 However, 2 crucial issues in the management of hypertension in patients with CKD are first, whether a specific blood pressure target may maximize renoprotection, and second, whether a specific drug may be beneficial, independent of blood pressure control. Concerning blood pressure targets, few randomized trials [13][14][15][16] have been conducted in patients with CKD to confirm the association of findings from these cohort studies. 10,11 In the Modification of Diet in Renal Disease (MDRD) Study, the largest randomized prospective trial performed to date (840 patients, mostly with nondiabetic kidney disease), tight blood pressure control (mean arterial pressure Յ92 mm Hg; ie, blood pressure, 125/75 mm Hg) did not improve the primary outcome of GFR reduction, doubling of serum creatinine level, or ESRD.…”

Does treatment of non-malignant hypertension reduce the incidence of renal dysfunction? A meta-analysis of 10 randomised, controlled trials

“…Trials of multiple risk factor interventions were excluded because of potential confounding by other therapies. Also excluded were trials that enrolled only patients with known renal insufficiency or established renal parenchymal disease [17][18][19] since this study was not designed to examine the effect of blood pressuring lowering in patients who already had renal dysfunction.…”