Diffuse toxic goiter in children: incidence at iodine deficient territories of the Russian Federation

Abstract

Time course of changes in the incidence of diffuse toxic goiter (DTG) in children aged 0-14years was studied in 1986-1999 at territories with slight iodine deficiency and normal radiation levels in the Central Federal Region of Russia (Belgorod, Voronezh, and Orel regions, a total of 45 territories, n = 665,987). The mean incidence of DTG over 14years in this cohort was 0.59per 100,000 children annually, which corresponds to the prevalence of this condition at a territory with slight and moderate iodine deficit. A notable increase in the incidence of DTG was observed during recent 5 years (1995-1999) in comparison with the beginning of observation (1986-1990): annual number of new cases and the morbidity level doubled (from 2.6+ 0.7 to 5.6+0.5, p - 0.01, and from 0.39 to 0.84, p < 0.03, respectively). The relative risk, of DTG in childhood increased to 2.15 (1.13-4.15, p < 0.029) in recent years; this is true mainly for pubertal girls. These negative shifts in DTG epidemiology among children in Central Russia were not caused by principal changes in the level of iodine consumption and were observed in the presence of persisting slight iodine deficiency under conditions of neglected overall iodine prevention.