Combined Triglyceride–High-density Lipoprotein Cholesterol Phenotypes and Cardiovascular Outcomes in Japanese Patients with Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention: Insights from Clinical Deep Data Accumulation System-PCI

AIMS: Despite intensive lipid-lowering therapy, residual cardiovascular risk remains prevalent among patients with coronary artery disease. Although triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) metabolism are closely interrelated, their combined prognostic significance in secondary prevention remains unclear. METHODS: This study analyzed the Clinical Deep Data Accumulation System- Percutaneous Coronary Intervention (CLIDAS-PCI) database, a multicenter Japanese registry of patients with acute coronary syndrome undergoing PCI. Patients were stratified into four combined TG-HDL phenotypic groups using guideline-consistent cutoff values for high TG (≥ 175 mg/dL) and low HDL-C (≤ 40 mg/dL) levels. The primary outcome was a composite of major adverse cardiac and cerebrovascular events plus hospitalization for heart failure and its components. RESULTS: Among 3,352 patients, high TG levels were not associated with the composite outcome but were consistently associated with an increased risk of recurrent myocardial infarction. Although low HDL-C levels were associated with increased cardiovascular risk, this association was attenuated after adjustment for renal function and nutritional status. Combined TG-HDL phenotyping revealed distinct risk profiles: patients with high TG and low HDL-C levels had the highest risk of recurrent myocardial infarction, while those with low TG and low HDL-C levels exhibited a markedly higher risk of cardiovascular death. CONCLUSIONS: In a Japanese secondary prevention cohort undergoing PCI, TG and HDLC demonstrated complementary and outcome-specific prognostic associations. Thus, combined TG-HDL phenotyping using guideline-based cutoffs may provide a simple and clinically relevant approach to stratifying residual cardiovascular risk beyond low-density lipoprotein cholesterol lowering.