Canada: Lower LDL Cholesterol and Cardiovascular Outcomes in T2D Patients

Lower LDL cholesterol in the first year after coronary revascularization in type 2 diabetes (T2D) patients is associated with improved cardiovascular outcomes in the long run, according to a recent study in the Journal of the American College of Cardiology.

Increased levels of low-density lipoprotein cholesterol (LDL-C) increase the risk of cardiovascular events, especially in high-risk populations such as patients with diabetes. The study by Michael E. Farkouh, University of Toronto, Toronto, Ontario, Canada, and colleagues aimed to determine the effect of LDL-C on the incidence of cardiovascular events either following a coronary revascularization procedure (percutaneous coronary intervention [PCI] or coronary artery bypass grafting [CABG]) or optimal medical therapy alone in patients with T2D and coronary heart disease.

For this purpose, the researchers undertook a patient-level pooled analysis of 3 randomized clinical trials. T2D patients were categorized according to LDL-C levels at 1 year following randomization. A total of 4,050 patients were followed for a median of 3.9 years after the index 1-year assessment.

The primary endpoint was major adverse cardiac or cerebrovascular events (MACCE: the composite of all-cause mortality, nonfatal myocardial infarction, and nonfatal stroke).

Key Findings of the Study

• Patients whose 1-year LDL-C remained ≥100 mg/dl experienced higher 4-year cumulative risk of MACCE (17.2% vs. 13.3% vs. 13.1% for LDL-C between 70 and <100 mg/dl and LDL-C <70 mg/dl, respectively).
• When compared with optimal medical therapy alone, patients with PCI experienced a MACCE reduction only if 1-year LDL-C was <70 mg/dl (hazard ratio: 0.61), whereas CABG was associated with improved outcomes across all 1-year LDL-C strata.
• In patients with 1-year LDL-C ≥70 mg/dl, patients undergoing CABG had significantly lower MACCE rates as compared with PCI.

"Lower LDL-C at 1 year in patients with coronary heart disease and T2D is associated with improved long-term MACCE outcome in those eligible for either PCI or CABG. When compared with optimal medical therapy alone, PCI was associated with MACCE reductions only in those who achieved an LDL-C <70 mg/dl. Thus, optimal LDL-C control may be pivotal to achieving optimal outcomes following PCI, which warrants further studies," concluded the authors.

The study, "Influence of LDL-Cholesterol Lowering on Cardiovascular Outcomes in Patients With Diabetes Mellitus Undergoing Coronary Revascularization," is published in the Journal of the American College of Cardiology.

DOI: https://www.jacc.org/doi/10.1016/j.jacc.2020.09.536