Cluster-Based Analysis of Lipid-Derived Profiles and Clinical Presentation in Premature Acute Coronary Syndrome.

OBJECTIVE

Premature acute coronary syndrome (ACS) is clinically heterogeneous, and routine lipid parameters may not fully capture lipid-related risk profiles in young patients. We investigated whether lipid-derived indices could identify clusters associated with index ACS presentation and long-term outcomes.

METHOD: This retrospective, single-center observational cohort study included patients aged ≤50 years who presented with first documented angiographically obstructive premature ACS and had complete lipid data. Standardized non-HDL-C, remnant cholesterol, TG/HDL-C ratio, and atherogenic index of plasma were analyzed using k-means clustering. Associations with STEMI presentation and a composite cardiovascular/cerebrovascular endpoint were evaluated using logistic and Cox regression analyses.

RESULTS

Of 1106 screened records, 195 were excluded because of incomplete lipid data or implausible lipid values, leaving 911 patients for analysis. At presentation, 152 patients (16.7%) had unstable angina, 224 (24.6%) had NSTEMI, and 535 (58.7%) had STEMI. Two clusters were identified: a lower atherogenic pattern (n=673, 73.9%) and a high atherogenic pattern (n=238, 26.1%). STEMI was less frequent in the high atherogenic pattern than in the lower atherogenic pattern (51.7% vs. 61.2%; P = 0.010) and remained independently associated after adjustment (OR, 0.69; 95% CI, 0.50-0.93; P = 0.016). In the MI-only sensitivity analysis, this association was attenuated and was no longer statistically significant. Sensitivity clustering yielded similar results. During a median clinical follow-up of 1370 days (IQR, 706-1991), 228 patients (25.0%) experienced the composite endpoint; the high atherogenic pattern was not independently associated with this outcome (HR, 1.11; 95% CI, 0.83-1.48; P = 0.496).

CONCLUSION

Lipid-derived clustering identified two phenotypic patterns associated with index ACS presentation but not with long-term composite outcomes. Prospective external validation is required.