Triglycerides and the Risk of Atherosclerotic Cardiovascular Events Across Different Risk Categories.

AIMS

To investigate the association between triglyceride levels and major adverse cardiovascular events (MACE) in primary and secondary prevention cohorts.

METHODS

This retrospective study was conducted with a nationwide health insurance claims database, which included approximately 3.8 million participants with medical checkups between January 2005 and August 2020 in Japan. The participants were classified into primary prevention (n=3,415,522) and secondary prevention (n=29,806) cohorts based on cardiovascular or cerebrovascular disease history. Each participant was categorized as having very low (triglyceride ＜50 mg/dL), low normal (50-99), high normal (100-149), or hypertriglyceridemia (≥ 150). The primary prevention cohort was further stratified into low-, intermediate-, and high-risk groups according to atherosclerotic cardiovascular diseases risk. Outcome was MACE, including acute myocardial infarction (AMI), unstable angina, ischemic stroke, and cardiac death.

RESULTS

Over a mean follow-up of 3.25 years, 0.3% and 2.6% MACE occurred in primary and secondary prevention, respectively. Hypertriglyceridemia was associated with high risk of MACE in the primary prevention, but not in the secondary prevention. A significant interaction was observed between prevention categories and the association of TG levels with MACE in those with TG ＜150 mg/dL and ischemic stroke in those with TG ≥ 150 mg/dL. The population-attributable fraction for hypertriglyceridemia in primary prevention was 4.1% for MACE. In primary prevention, lower risks of AMI were observed in the lower TG category compared to the current threshold.

CONCLUSIONS

This study suggests distinct triglyceride thresholds for MACE risk in primary and secondary prevention cohorts, requiring further prospective validation for clinical implementation.