FREQUENCY OF HYPERTHYROIDISM IN PATIENTS PRESENTING WITH ATRIAL FIBRILLATION

Background: Hyperthyroidism is a recognized secondary cause of atrial fibrillation (AF) and contributes to increased morbidity. Early identification is essential for timely management. Objective: To determine the frequency of hyperthyroidism in patients presenting with atrial fibrillation and its associated factors. Study Design: Cross-sectional study. Setting: Department of Cardiology, Khyber Teaching Hospital, Peshawar, Pakistan. Duration of Study: From 07-February-2025 to 07-June-2025. Methods: A total of 260 patients with ECG-confirmed AF were enrolled. Diagnosis of hyperthyroidism was based on clinical features (weight loss, palpitations, tremors) and laboratory analysis (serum TSH <0.5 mIU/L with either free T3 >450 pg/dL or free T4 >1.8 ng/dL). Data on demographics, BMI, and comorbidities were collected. Statistical analysis was performed using SPSS; p-values <0.05 were considered significant. Results: The mean age was 51.05 ± 12.38 years, with 135 males (51.9%) and 125 females (48.1%). Hyperthyroidism was identified in 22 patients (8.5%). Female gender (p = 0.04) and presence of comorbidities (p = 0.003) were significantly associated with hyperthyroidism, while age and BMI showed no significant association. Conclusion: Hyperthyroidism was present in 8.5% of patients with AF, showing a significant association with female gender and comorbid conditions. Routine thyroid function screening is recommended in AF patients, particularly in females and those with comorbidities.