This study used galectin-3 serum levels upon hospitalization to predict 30 day mortality. Galectin-3 serum levels higher than 35.3 ng/ml was the cutoff point that predicted mortality, intensive care admission, or ARDS. A Galectin-3 cut-off of 35.3 ng/ml was fixed to achieve a sensitivity of 80% and a specificity of 92.1% for mortality prediction, with an AUC value of 0.906 (95% CI 0.85–0.96, p < 0.0001).