Association between Non-Lipid Residual Risk Factors and Cardiovascular Events in Patients with Stable Coronary Artery Disease Treated with Pitavastatin: An Observation from the REAL-CAD Study

Abstract

Aims: We aimed to investigate the association between non-lipid residual risk factors and cardiovascular events in patients with stable coronary artery disease (CAD) who achieved low-density lipoprotein cholesterol (LDL-C) ＜100 mg/dL from the Randomized Evaluation of Aggressive or Moderate Lipid Lowering Therapy with Pitavastatin in Coronary Artery Disease (REAL-CAD) study.

Methods: The REAL-CAD study was a prospective, multicenter, open-label trial. As a sub-study, we examined the prognostic impact of non-lipid residual risk factors, including blood pressure, glucose level, and renal function, in patients who achieved LDL-C ＜100 mg/dL at 6 months after pitavastatin therapy. Each risk factor was classified according to severity. The primary outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal ischemic stroke, and unstable angina requiring emergency hospitalization.

Results: Among 8,743 patients, the mean age was 68±8.2 years, and the mean LDL-C level was 84.4±18 mg/dL. After adjusting for the effects of confounders, an estimated glomerular filtration rate (eGFR) ≤ 60 mL/min/1.73 m² showed the highest risk of the primary outcome (hazard ratio [HR] 1.92; 95% confidence interval [CI] 1.45-2.53). The combination of eGFR ≤ 60 and hemoglobin A1c (HbA1c) ≥ 6.0% also showed the highest risk of all-cause death (HR, 2.42; 95% CI, 1.72-3.41).

Conclusions: In patients with stable CAD treated with pitavastatin and who achieved guidelines-directed levels of LDL-C, eGFR and HbA1c were independently associated with adverse events, suggesting that renal function and glycemic control could be residual non-lipid therapeutic targets after statin therapy.