Association of serum uric acid with benefits of intensive blood pressure control

Introduction and objectives: Intensive systolic blood pressure (SBP) control improved outcomes in the Strategy of Blood Pressure Intervention in the Elderly Hypertensive Patients (STEP) trial. Whether the serum uric acid concentration at baseline alters the benefits of intensive SBP control is unknown.Methods: The STEP trial was a randomized controlled trial that compared the effects of intensive (SBP target of 110 to < 130 mmHg) and standard (SBP target of 130 to < 150 mmHg) SBP control in Chinese patients aged 60 to 80 years with hypertension. The primary outcome was a composite of cardiovascular disease events. This post hoc analysis was performed to examine whether the effects of intensive SBP intervention differed by the baseline uric acid concentration using 2 models: restricted cubic spline curves and subgroup analyses, both based on the Fine-Gray subdistribution hazard model in the analysis of the primary outcome and secondary outcomes (excluding all-cause death). In the analysis of all-cause death, the Cox regression model was used. We also examined the change in the follow-up uric acid concentrations.Results: Overall, the risk of the primary outcome rose as the cumulative uric acid concentration increased in both the intensive and standard treatment groups. Patients with intensive treatment had a lower multivariable-adjusted subdistribution hazard ratio for the primary outcome, but with a wide overlap of 95%CI. Next, we stratified patients according to their baseline uric acid concentration (tertile 1 [T1], < 303.0 mmol/L; tertile 2 [T2], 303.0 to < 375.8 mmol/L; and tertile 3 [T3], >= 375.8 mmol/L). Subgroup analyses using tertiles provided HRs and 95%CI in T1 (HR, 0.55; 95%CI, 0.36-0.86; P = .008), T2 (HR, 0.80; 95%CI, 0.56-1.14; P = .22) and T3 (HR, 0.86; 95%CI, 0.60-1.21; P = .39), with an interaction P value of .29. The results for most of the secondary outcomes followed the same trends.Conclusions: There was no evidence that the benefit of the intensive SBP control differed by baseline uric acid concentrations. This trial was registered at ClinicalTrial.gov (Identifier: NCT03015311).(c) 2023 Published by Elsevier Espana, S.L.U. on behalf of Sociedad Espanola de Cardiolog & iacute;a.