Intensive Home Blood Pressure Lowering in Patients With Advanced CKD

Rationale & objective: Optimal blood pressure (BP) targets in advanced chronic kidney disease (CKD) are controversial. More intensive BP lowering in the setting of advanced CKD is thought to be associated with risk of acute kidney injury, hyperkalemia, and end-stage kidney disease. We conducted a pilot trial of intensive BP control to determine if lower home systolic BP (SBP) targets can be safely achieved for patients with CKD through titration of BP medications using in-home measured BP.

Study design: Nonblinded randomized controlled trial.

Setting & participants: 108 patients with advanced CKD (estimated glomerular filtration rate≤30mL/min/1.73m²) and hypertension.

Interventions: Participants were randomized either to a target SBP goal of<120mm Hg (N=66) or a less intensive SBP goal (N=42). Antihypertensive medications were titrated to achieve the target home SBP range in the first 4 months of the study and maintained until the end of the study. Home BP was measured using a wireless Bluetooth-enabled monitor that transmitted readings to providers in real-time.

Outcome: The primary efficacy outcome was the difference in achieved clinic SBP between the 2 study arms from months 4-12. Safety outcomes included hyperkalemia, a composite outcome of falls or syncope, and onset of need for dialysis or kidney transplantation.

Results: The mean clinic SBP at month 12 was 124.7mm Hg in the intensive SBP group versus 138.2mm Hg in the less intensive SBP group. Averaged over months 4-12, the achieved mean clinic SBP in the intensive SBP arm was 11.7mm Hg ([95% CI, 7.5-16], P<0.001), lower than the mean SBP achieved in the less intensive SBP arm. Primary safety outcomes were not statistically significantly different between the 2 arms (all P>0.05).

Limitations: Small sample size, which may have limited our ability to detect clinically significant differences in rates of adverse outcomes, and single-center design.

Conclusions: A clinic SBP goal of<120mm Hg is feasible to achieve with the help of real-time home BP monitoring and appears to be safe in this study population with advanced CKD. Larger trials to determine optimal BP targets in advanced CKD and the risks and benefits associated with more intensive BP control are warranted.

Funding: Grant from an educational institution (UCSF Research Allocation Program award).

Trial registration: Registered at ClinicalTrials.gov with study number NCT02975505.

Plain-language summary: We conducted a pilot trial to test the feasibility of lowering blood pressure (BP) intensively through the use of home BP monitoring in patients with low kidney function. We found that home BP monitoring used to guide antihypertensive medication dosing permitted better BP control for patients with chronic kidney disease and did not appear to be associated with major adverse events.