Intensive Systolic Blood Pressure Reduction and Kidney and Cardiovascular Outcomes: A Secondary Analysis of a Randomized Clinical Trial.

IMPORTANCE

Intensive blood pressure (BP) control is effective in reducing major cardiovascular events. However, whether the reduction of systolic BP may lead to kidney injury remains controversial.

OBJECTIVE

To elucidate the association of intensive BP control with kidney and cardiovascular outcomes in individuals with hypertension without chronic kidney disease.

DESIGN, SETTING, AND PARTICIPANTS: This study is a secondary analysis of the China Rural Hypertension Control Project (CRHCP), an open-label, blind-end-point cluster randomized trial conducted from May 8, 2018, to March 15, 2023, in 326 villages in China. Patients with a baseline estimated glomerular filtration rate (eGFR) of 60 mL/min/1.73 m2 or greater were randomized to an intervention or usual care group, stratified according to eGFR level.

EXPOSURES

A nonphysician community health care professional implemented a multifaceted intervention program after training to achieve a BP treatment goal of less than 130/80 mm Hg.

MAIN OUTCOMES AND MEASURES

Kidney outcome was defined as an eGFR decrease of 30% to a rate less than 60 mL/min/1.73 m2. Composite cardiovascular outcomes included cardiovascular death, stroke, myocardial infarction, and heart failure.

RESULTS

A total of 33 332 patients with a baseline eGFR of 60 mL/min/1.73 m2 or greater were included in this subgroup analysis (mean [SD] age, 62.8 [9.1] years; 61.3% female). After 36 months of follow-up, in 7562 participants with eGFRs between 60 and 90 mL/min/1.73 m2, 121 participants in the intervention group and 101 in the usual care group (risk ratio, 1.17; 95% CI, 0.82-1.62; P = .36) experienced kidney outcome, which was not statistically significant. As for cardiovascular outcomes, 210 participants (2.0% per year) in the intervention group and 346 participants (3.3% per year) in the usual care group had the composite cardiovascular disease outcome, and the disparity between the 2 groups was statistically significant (hazard ratio, 0.57; 95% CI, 0.47-0.68; P < .001).

CONCLUSIONS AND RELEVANCE

This secondary analysis of the CRHCP study suggests that intensive BP control was associated with reduced incidence of the composite cardiovascular disease outcome but not increased risk of kidney injury in patients without chronic kidney disease. These findings provide further evidence supporting the implementation of intensive BP control in patients without chronic kidney disease.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03527719.