Thyroid Peroxidase Antibody as a Marker for Persistent Hypothyroidism Symptoms Despite Normal TSH Levels: A Cross-Sectional Study

This study investigates why some patients with primary hypothyroidism continue to experience symptoms such as fatigue, depression, and hair loss despite having normal TSH levels and adequate levothyroxine treatment. The study involved 111 adults divided into two groups: those with persistent symptoms and those without. Results showed a significant association between higher levels of thyroid peroxidase antibodies (TPO ≥ 35) and the persistence of symptoms, including hair loss and poor concentration. The findings suggest that TPO antibodies can be a useful marker for identifying patients who may continue to experience symptoms despite normal TSH levels, indicating that TSH alone may not be sufficient to assess treatment adequacy in hypothyroid patients.