Thyroid dysfunction does not predict mortality in heart failure, finds study
UK: Researchers exploring connection between thyroid function and prognosis in CHF (chronic heart failure) patients found that although thyroid dysfunction is associated with poorer survival, it does not predict mortality. The findings of the study are published in the American Journal of Cardiology.
Heart failure was defined as signs and symptoms of the disease and either left ventricular systolic dysfunction (LVSD) mild or worse or no LVSD and raised amino-terminal pro-B-type natriuretic peptide (NT-proBNP) levels (>125 ng/L; heart failure with normal ejection fraction [HFnEF]).
Euthyroid state was defined as a thyroid-stimulating hormone (TSH) level between 0.35 and 4.70 mIU/l, hypothyroidism as TSH >4.70 mIU/l, and hyperthyroidism as TSH <0.35 mIU/l.
Key findings of the study include:
- 2997 patients had HFrEF and 1995 patients had HFnEF-- 90% patients were euthyroid, 6% were hypothyroid, and 4%were hyperthyroid.
- In univariable analysis, both hypothyroid patients (hazard ratio [HR] 1.25) and hyperthyroid patients (HR 1.21) had a greater risk of death compared with euthyroid patients.
- There was a U-shaped relation between TSH and outcome.
- Increasing TSH was a predictor of mortality in univariable analysis (HR 1.02), but the association disappeared in multivariable analysis.
- The three strongest predictors of adverse outcome were increasing age, increasing NT-proBNP, and higher NYHA class.
"Although thyroid dysfunction is associated with worse survival in patients with CHF, it is not an independent predictor of mortality," concluded the authors.
The study, "Relation Between Thyroid Function and Mortality in Patients With Chronic Heart Failure," is published in the American Journal of Cardiology.
DOI: https://www.ajconline.org/article/S0002-9149(20)31140-1/fulltext
