RESUMO
AIM: This study aimed to evaluate the association between serum myostatin levels, hospital mortality, and muscle mass and strength following ST-segment elevation myocardial infarction (STEMI). METHODS: This was a prospective observational study. Within 48 hours of admission, bioelectrical impedance and handgrip strength were assessed and blood samples collected for myostatin evaluation. Hospital mortality was recorded. A multiple logistic regression model was also constructed, adjusted by parameters that exhibited significant differences in the univariate analysis, to evaluate the association between myostatin levels and hospital mortality. RESULTS: One hundred and two (102) patients were included: mean age was 60.5±10.6 years, 67.6% were male, and 6.9% died during hospital stay. Univariate analysis showed that patients with lower myostatin levels had higher mortality rates. Serum myostatin levels positively correlated with handgrip strength (r=0.355; p<0.001) and appendicular skeletal muscle mass index (r=0.268; p=0.007). Receiver operating characteristic (ROC) curve analysis revealed that lower myostatin levels were associated with hospital mortality at the <2.20 ng/mL cut-off. Multiple logistic regression showed that higher serum myostatin levels were associated with reduced hospital mortality when adjusted by ß blocker use (OR, 0.228; 95% CI, 0.054-0.974; p=0.046). CONCLUSIONS: Serum myostatin concentrations positively correlated with muscle mass and strength in STEMI patients. Further assessment of serum myostatin association with mortality should be conducted using a larger sample and assessing the additive value to the Global Registry of Acute Coronary Events (GRACE) or thrombolysis in myocardial infarction (TIMI) risk scores.