Frequency of Thyroid Dysfunction in Patients with Heart Failure and Reduced Ejection Fraction

Objectives: Heart failure is a major global health problem frequently encountered in medical emergencies, pulmonology, and cardiology units. The burden of heart failure continues to rise worldwide, including in low- and middle-income countries such as Pakistan. Thyroid dysfunction, a common endocrine disorder, has well-recognized effects on cardiovascular structure and function and may influence the clinical course of heart failure. This study aimed to determine the frequency and pattern of thyroid dysfunction among patients with heart failure and reduced ejection fraction. Methodology: A hospital-based cross-sectional study was conducted in the Cardiology Department of Bahria International Hospital from May 18, 2025, to September 30, 2025. A total of 163 patients with heart failure and reduced ejection fraction were enrolled using non-probability consecutive sampling. Thyroid function was assessed by measuring serum thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4). Data were analyzed using SPSS version 28. Results: The mean age of participants was 51.45 ± 11.67 years, and the mean ejection fraction was 32.25 ± 4.41%. Thyroid dysfunction was identified in 48 patients (29.4%). Hypothyroidism was the most prevalent abnormality, observed in 31 patients (19%), while 17 patients (10.4%) had hyperthyroidism. No statistically significant association was found between thyroid dysfunction and age or gender. Conclusion: Thyroid dysfunction is common among patients with heart failure and reduced ejection fraction, with hypothyroidism being the most frequent abnormality. Routine assessment of thyroid function may be beneficial in patients with heart failure. Further studies are warranted to evaluate the clinical outcomes following correction of thyroid dysfunction.