Circulating musclin as a potential prognostic biomarker for major adverse cardiovascular events in surgically treated acute aortic dissection: a retrospective cohort study

Background Musclin is a skeletal muscle-derived myokine with reported cardioprotective effects; however, its prognostic relevance in acute aortic dissection (AAD) remains uncertain. This study examined whether admission Musclin levels were associated with postoperative major adverse cardiovascular events (MACE) and whether they added prognostic information beyond conventional clinical indicators. Methods We retrospectively enrolled 108 surgically treated AAD patients from 2022 to 2023. Musclin levels were measured by ELISA in residual serum samples collected at admission. The primary endpoint was composite MACE. Kaplan–Meier survival analysis, multivariate Cox regression, time-dependent ROC, IDI and NRI were used to evaluate the predictive and incremental value of Musclin. Results During 400-day follow-up, 36 patients (33.3%) developed MACE. The CART-derived optimal Musclin cutoff was 4.815 ng/mL. Kaplan–Meier analysis showed that low Musclin group had significantly higher MACE cumulative incidence than high Musclin group (48.2% vs. 17.3%, log-rank P < 0.001). Multivariate Cox regression confirmed circulating Musclin associated with a lower risk of MACE (HR = 0.314, 95%CI: 0.104–0.943, P = 0.039). Time-dependent AUC analysis demonstrated that the combined model incorporating Musclin (model 2) achieved superior AUC compared with the clinical model (model 1). Even at the 250-day time point, where the incremental gain ( Δ AUC) was minimal, the combined model still exhibited significantly better discriminative performance (0.876 vs. 0.837, DeLong P = 0.013). At the 250-day landmark, IDI was 0.153 (95%CI: 0.018–0.286, P = 0.012) and overall NRI was 0.167 (95%CI: 0.003–0.336, P = 0.044), with event-specific NRI reaching 0.361 ( P = 0.012). Sensitivity analyses yielded directionally consistent associations when Musclin was analyzed using the cohort median or as a continuous variable. Conclusions In this single-center retrospective cohort, lower admission Musclin was associated with a higher risk of postoperative MACE. Musclin may be a severity-related biomarker that could complement conventional risk indicators, but its independent clinical utility, optimal threshold, and role in risk stratification require prospective multicenter validation with comprehensive perioperative adjustment before clinical use.