Regional Differences of Drinking Water Iodine and Its Association with Thyroid Disorder and Serum Iodine

Abstract

The study aims to evaluate relationship between drinking water iodine and serum iodine with thyroid disorders in patients with symptomatic thyroid disease in Erbil province, Iraq. Outpatients attending Rizgariy and Hawler teaching hospital, Erbil province, were participated in this cross sectional study and samples of drinking water were collected randomly from different geographical region of Erbil province. Biochemical analyses included; serum thyroid hormones, serum iodine and drinking water iodine. Level of water and serum iodine were deficient 24.1± 6.8 μg/l (SD)μg/l and 24.4 ± 21.4 (SD) μg/l respectively. Highest level of the water iodine was in south west of Erbil city and the lowest one was in the east districts. Water iodine showed significant negative correlation with thyroid stimulating hormone (TSH) in patients with abnormal thyroid function and significant increase risk of hypothyroidism in regions with low water iodine. 20% of patient had hypothyroidism. Serum iodine didn’t correlated with water iodine while there was significant negative correlation of it with TSH hormone. Deficiency of drinking water iodine reflects effect of environmental factors on water quality. It is a potential risk factor for developing thyroid disorder especially hypothyroidism in reproductive age of housewives. Continued monitoring treatment and iodized salt programs could prevent hypo and hyperthyroidism.