Predictive value of combined serum FGF21 and free T3 for survival in septic patients

We examined the correlation between thyroid hormone (TH) concentrations and the serum fibroblast growth factor 21 (FGF21) concentration in septic patients and to assess the collaborative value of these factors in predicting 28-day mortality in septic patients. A total of 120 consecutive patients with sepsis were divided into two groups according to their survival or death within 28 days after initial diagnosis of sepsis. Patients in the non-survivor group had significantly higher serum FGF21 concentrations but lower total and free triiodothyronine (T3) and tetraiodothyronine (T4) concentrations than those in the survivor group. Thyroid hormone concentrations, including T3, free T3, T4 and free T4, were significantly negatively correlated with the ∆SOFA and APACHE II scores as well as the serum FGF21, IL-6, tumor necrosis factor-α, IL-10, procalcitonin, and C-reactive protein concentrations. Logistic regression analysis showed that the ∆SOFA score, serum FGF21 concentration, and free T3 concentration were significant predictors of 28-day mortality. The model with variables of ∆SOFA score and serum FGF21 and free T3 concentrations had the greatest area under the curve of 0.969. The addition of free T3 and serum FGF21 to ∆SOFA score provided a significantly improved ability to predict 28-day mortality in septic patients. •Non-survivor septic patients had higher serum FGF21 but lower TT3, FT3, TT4 FT4.•Thyroid hormone levels negatively correlated with ∆SOFA, APACHE II and serum FGF21 in septic patients.•∆SOFA score, serum FGF21 level, and FT3 level were predictors of 28-day mortality.•Addition of FT3 and FGF21 to ∆SOFA improved mortality prediction in septic patients.