Monitoring the severity of iodine deficiency disorders in Uganda.

BACKGROUND: Iodine deficiency disorders (IDD) cover a variety of pathological conditions including goitre, mental retardation and perinatal mortality in millions of individuals globally. IDD was initially identified as a problem in 1970 and was confirmed in 1991. In 1993, the Uganda government introduced a policy of Universal Salt Iodization (USI) requiring all household salt to be iodized. After 5 years this study evaluates the USI programme. OBJECTIVES: To determine goitre prevalence rate, establish the proportion of household consuming iodized salt and determine the levels of iodine intake in the sample districts. METHODS: A sample of 2880 school children aged 6-12 years from 72 Primary schools in 6 districts of Uganda was studied in October 1999. Goitre was established by palpation, salt iodine was analysed by thiosulphate titration, while urinary iodine was analyzed using ICCIDD recommended method F in which iodine is detected colorimetrically at 410 nm. RESULTS: The over all total goitre rate was 60.2% down from 74.3 in 1991 and visible goitre was 30% down from 39.2% in 1991. The proportion of households taking adequately iodized salt was 63.8% and the median urinary iodine was 310 microg/L. Whereas 36% of 95 urine samples analysed in 1991 had urinary iodine below 50 microg/L, only 5% of the 293 urine samples studied in 1999 had the same urine levels. This represents a considerable improvement in iodine intake, which is confirmed by the fact that 63.8% of the study households consume adequately iodized salt. If maintained and evenly spread, this will enable Uganda to control IDD. CONCLUSION: USI has improved iodine intake in Uganda. However, iodine malnutrition is still a severe public health problem because some communities in this study such as in Kisoro still have low iodine consumption, while others such as Luwero now have iodine excess. The latter is likely to predispose to hyperthyroidism. RECOMMENDATION: The national set standard of household salt iodine of 100 ppm be revised. Locally produced salt be iodized, and a national iodine monitoring programme be instituted to ensure evenly spread consumption of adequately iodized salt by all communities in the country.