A longitudinal observational study on activated partial thromboplastin time in hypothyroidism and effect of thyroxine supplementation

Background: Hypothyroidism is a common condition characterized by thyroid hormone deficiency, which, if untreated, can lead to severe health consequences and even death. Due to the wide range of clinical presentations and non-specific symptoms, hypothyroidism is primarily diagnosed biochemically. It can result from congenital thyroid abnormalities or iodine deficiency. Aims and objectives: Aim: To evaluate the correlation between hypothyroidism and Activated Partial Thromboplastin Time (aPTT) and assess the effect of thyroxine supplementation. Objective: To study the impact of levothyroxine supplementation on aPTT in hypothyroid patients. Materials and methods: This observational study was conducted at the General Medicine outpatient clinic and inpatient wards at Al-Ameen Medical College and Hospital, Vijayapura, from September 2022 to March 2024. A total of 80 hypothyroid patients of both sexes were included. TSH, Free T4, and aPTT levels were measured with appropriate aseptic precautions. Results: The majority of subjects were females (90%), with the highest proportion (31.3%) aged 26-35 years. The mean ± SD of pre-thyroxine TSH was 25.453 ± 19.9073, which significantly decreased to 4.299 ± 0.6738 post-thyroxine. aPTT values also decreased significantly post-treatment. A positive correlation was found between TSH and aPTT, while aPTT had a negative correlation with T3 and T4 levels. Conclusion: aPTT is significantly elevated in hypothyroid patients and shows a positive correlation with TSH levels. Regular monitoring of aPTT should be included in the follow-up of hypothyroid patients.