Iodine nutrition status in Graves' disease: A single-center study from Bangladesh

Abstract

Context: An increase in occurrence of Graves' disease (GD) has been reported in many countries after the introduction of the salt iodization program. Aims: To observe iodine nutrition status in GD. Settings and Design: Cross-sectional observational study conducted in the Department of Endocrinology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from May 2013 to September 2014. Methods and Material: This study included 140 GD patients (55 newly detected, 85 already under treatment). Urinary iodine concentration (UIC) was measured in spot urine sample following wet digestion method. The iodine nutrition status was categorized according to the internationally recommended cutoffs of UIC (excessive: ≥300 μg/L, more than optimal: 200-299 μg/L, optimal: 100-199 μg/L, deficiency: Results: The median UIC in subjects with Graves' disease was 96.69 μg/L. 21.2% of the study subjects had iodine status to be considered as more than optimal or excessive, 25.7% had optimal iodine level, and more than half (51.4%) had iodine deficiency. The mean UIC were similar in newly diagnosed and treated groups, and among subjects with different thyroid functional status. UIC did not differ among male and female subjects and among subjects from different socioeconomic groups. UIC showed no correlations with age, socioeconomic condition, the family history of thyroid disease, TSH, FT4, and thyroid function status of the study participants. Conclusions: Effective monitoring of salt iodization program is needed to prevent iodine-excess related increase in the prevalence of Graves' disease.