Medication Adherence of Children with Congenital Hypothyroidismin Iran: A National Cross-Sectional Study

Background: Congenital hypothyroidism is the most common preventable and treatable cause of intellectual disability inchildren. A key component of the surveillance system for congenital hypothyroidism is ensuring a regular treatment programfor affected children. Despite nearly 20 years since the successful implementation of the newborn screening program forhypothyroidism in Iran, a comprehensive evaluation of patients' adherence to treatment has not been conducted. Objectives: The aim of this study was to investigate the adherence to treatment among patients with congenitalhypothyroidism in Iran. Methods: In this national cross-sectional study conducted in 2024, the adherence to treatment of 400 children with congenitalhypothyroidism born between 2019 and 2023 in Iran was examined using the Morisky Medication Adherence Scale. The patientswere randomly selected from national registry data. Data were analyzed using chi-squared tests, Fisher's exact test, and logisticregression in Stata software version 16. Results: The mean and standard deviation of medication adherence was 6.35 +/- 1.41. Overall, adherence was good (>= 6) in 284(71.0%) of the study participants. In the univariate analysis, the most significant factors influencing adherence were place ofresidence, higher maternal education, lower paternal education, and type of congenital hypothyroidism (CH). In themultivariate analysis, children with permanent CH had good adherence, and parental education was not statistically significant(P > 0.05). Conclusions: The results of this study showed that medication compliance in more than two-thirds of hypothyroid childrendiagnosed by national newborn screening is good. Given the importance of treatment in these patients, it is recommended thatintervention plans be implemented, including educational programs and active follow-up of patients to increase compliance