Determinants of post-discharge LDL-C testing and target attainment after acute coronary syndrome: a 10-year population-based study.

BACKGROUND: Despite guideline recommendations for early lipid monitoring after acute coronary syndrome (ACS), follow-up low-density lipoprotein cholesterol (LDL-C) testing remains inconsistent in routine clinical practice. We aimed to characterize patients without post-ACS LDL-C testing and identify clinical factors associated with LDL-C target attainment among those tested. METHODS: Consecutive ACS hospitalizations within a large healthcare system between 2013 and 2023 were analysed. Patients surviving ≥6 months post-ACS were included, with LDL-C testing patterns assessed within 6 months post-discharge. Multivariable logistic regression identified factors associated with absence of LDL-C testing and failure to achieve LDL-C <70 mg/dL. RESULTS: Among 42,056 eligible patients, 22,722 (54.0%) underwent LDL-C testing, whereas 19,334 (46.0%) did not. Non-testing was associated with younger age, male sex, lower socioeconomic status, and reduced use of lipid-lowering therapy (LLT) at discharge (all p<0.001). Absence of early post-discharge LLT dispensing was the strongest predictor of non-testing (OR 7.90, 95% CI 7.10-8.81), whereas combination therapy was associated with lower odds of non-testing (OR 0.79, 95% CI 0.69-0.90). Among tested patients, 59.7% achieved LDL-C <70 mg/dL, with combination therapy associated with higher target attainment (OR 1.52, 95% CI 1.26-1.83) and no LLT associated with lower attainment (OR 0.49, 95% CI 0.42-0.58). LDL-C control improved over time, paralleling evolving guidelines. CONCLUSION: LDL-C follow-up and attainment after ACS remain suboptimal. Patients at risk for absent testing may be recognized before discharge, creating opportunities for proactive intervention. Intensive LLT were associated with better LDL-C control, emphasizing the value of coordinated follow-up strategies.