EFFECT ON INFANT-MORTALITY OF IODINATION OF IRRIGATION WATER IN A SEVERELY IODINE-DEFICIENT AREA OF CHINA

Background Hotien county in Xinjiang province, China, is an area of se vere iodine deficiency and has a high infant-mortality rate. We invest igated whether iodine replacement through iodination of the irrigation water would decrease infant mortality. Methods We added potassium iod ate to irrigation water over a 2 to 4 week period beginning in 1992 in certain areas of three townships (Tusala, Long Ru, and Bakechi). Logi stic regression analysis was used to compare the odds ratios for infan t and neonatal mortality in treated and untreated areas. Findings The median urinary iodine concentration significantly increased in women o f child-bearing age from <10 mu g/L to 55 mu g/L Infant-mortality rate s decreased in the treated areas of Long Ru (mean [SD]) 58.2 [4.4] per 1000 births to 28.7 [7.1] per 1000 births), Tusala (47.4 [12.4] per 1 000 births to 19.1 [1.5] per 1000 births), and Bakechi (106.2 [9.5] pe r 1000 births to 57.3 [7.3] per 1000 births). Similar results were als o seen for neonatal mortality. On regression analysis iodine treatment and time were significant independent predictors of infant mortality. Interpretation iodine supplementation of irrigation water in areas of severe iodine deficiency decreases neonatal and infant mortality. iod ine replacement has probably been an important factor in the national decrease in infant mortality in China.