Association of baseline serum cholesterol with benefits of intensive blood pressure control

Background: Intensive systolic blood pressure (SBP) control improved outcomes in the Strategy of Blood Pressure Intervention in the Elderly Hypertensive Patients (STEP) trial. Whether baseline serum lipid parameters influence the benefits of intensive SBP control is unclear. 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. A total of 8283 participants from the STEP study were included in this post hoc analysis to examine whether the effects of the SBP intervention differed by baseline low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) concentrations. Results: Regardless of the randomized SBP intervention, baseline LDL-C and non-HDL-C concentrations had a J-shaped association with the hazard of the primary outcome. However, the effects of the intensive SBP intervention on the primary outcome were not influenced by baseline LDL-C level (P for interaction = 0.80) and non-HDL-C level (P for interaction = 0.95). Adjusted subgroup analysis using tertiles in LDL-C1 (hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.52-1.13; P = 0.18), LDL-C2 (HR, 0.81; 95% CI, 0.55-1.20; P = 0.29), and LDL-C3 (HR, 0.68; 95% CI, 0.47-0.98; P = 0.04) was provided, with an interaction P value of 0.49. Similar results were showed in non-HDL-C1 (HR, 0.87; 95% CI, 0.59-1.29; P = 0.49), non-HDL-C2 (HR, 0.70; 95% CI, 0.48-1.04; P = 0.08), and non-HDL-C3 (HR, 0.67; 95% CI, 0.47-0.95; P = 0.03), with an interaction P-value of 0.47. Conclusion: High baseline serum LDL-C and non-HDL-C concentrations were associated with increased risk of primary cardiovascular disease outcome, but there was no evidence that the benefit of the intensive SBP control differed by baseline LDL-C and non-HDL-C concentrations.