[Clinical features and prognosis of patients hospitalized with heart failure and low T3 syndrome].

Objective: To investigate the association between triiodothyronine (T₃) and inflammatory factors, and its potential effect on long-term outcomes in hospitalized patients with heart failure (HF). Methods: A total of 2 475 patients with HF admitted in Heart Failure Care Unit were consecutively enrolled in this retrospective cohort study from December 2006 to June 2018. Patients were divided into low T₃ syndrome group (n=610, 24.6%) and normal thyroid function group (n=1 865, 75.4%). The median follow-up time was 2.9 (1.0, 5.0) years. A total of 1 048 all-cause deaths were recorded at the final follow-up. The effects of free T₃ (FT₃) and high-sensitivity C-reactive protein (hsCRP) on the risk of all-cause death were evaluated by Cox regression analysis and Kaplan-Meier analysis. Results: The age of the total population was 19-95 (57±16) years, 1 823 cases (73.7%) were male. Compared to those with normal thyroid function, albumin [(36.5±5.4) vs. (40.7±4.7) g/L], hemoglobin [(129.4±25.1) vs. (140.6±20.6) g/L], total cholesterol [3.6 (3.0, 4.4) vs. 4.2 (3.5, 4.9) mmol/L] (all P<0.001) were lower, Whereas age [(60.5±16.0) vs. (55.2±15.4) years], creatinine [105.0 (83.6, 137.0) vs. 87.8 (75.6, 106.3) mmol/L], log N-terminal B-type natriuretic peptide [(8.2±1.3) vs. (7.2±1.4) ng/L] were higher in LT₃S patients (all P<0.001). In Kaplan-Meier survival analysis, patients with lower FT₃ and higher hsCRP had significantly lower cumulative survival (P<0.001), lower FT₃ combined with higher hsCRP subgroup had the highest risk of all-cause death (P_trend<0.001). In multivariate Cox regression analysis, LT₃S was an independent predictor of all-cause mortality (HR=1.40, 95%CI 1.16-1.69, P<0.001). Conclusion: LT₃S is an independent predictor of poor prognosis in patients with heart failure. FT₃ combined with hsCRP improve the predictive value of all-cause death in hospitalized patients with heart failure.