To Assess Prevalence of Thyroid Dysfunction in Patients with Heart Failure and Impact on Its Prognosis.

Objective: To evaluate the prevalence of thyroid dysfunction in patients with heart failure (HF) and its impact on prognosis, specifically regarding hospital stay duration.

Methods: One hundred eighty-five HF patients aged >18 years were enrolled, and the study was conducted at Swaroop Rani Nehru Hospital between 21^st July 2021, and 20^th July 2022. All patients diagnosed with HF underwent demographic, clinical, hematological, biochemical, and thyroid function test (TFT) evaluations. Thyroid stimulating hormone (TSH) > 4.94 mIU/L was diagnosed as hypothyroidism, and TSH < 0.5 mIU/L was taken as hyperthyroidism, whereas those with normal TFT were defined as euthyroidism. Patients were monitored until discharge or final outcome. Data analysis was done using Statistical Package for the Social Sciences (SPSS) software 21.

Results: Thyroid disorders were seen in 28.6% of patients, with 6.5% having hyperthyroidism and 22.2% hypothyroidism. Thyroid disorders were significantly associated with higher New York Heart Association (NYHA) class (3/4), serum urea, serum creatinine, and lower hemoglobin levels. However, age, sex, or brain natriuretic peptide (BNP) were not significantly associated with thyroid disorders. There was no significant difference in HF patients' length of hospital stay with or without hypothyroidism. Though 6.5% of HF patients died during the course of the study, this was not statistically significant.

Conclusion: Thyroid disorders are highly prevalent among HF patients and have a significant clinical impact on their prognosis. Patients with thyroid disorders exhibited anemia, higher NYHA class, greater renal dysfunction, and longer hospital stays. Future studies are needed in this field. Clinicians should consider screening HF patients for thyroid dysfunction to improve patient outcomes.