India endemic goiter

Stanbury, J.B. and Hetzel, B.S. (1983). Endemic Goiter and Endemic Cretinism Iodine Nutrition in Health and Disease. Wiley Eastern Limited, New Delhi, India. 

In order to substantiate the role of iodine deficiency as the causative factor of endemic goiter in the Himalayan belt and to study the effectiveness of iodine prophylaxis, a prospective study was organized in 1956 in a population of approximately 100000 persons in the Kangra Valley of Himachal Pradesh in India (Table 79.3) (Sooch and Ramalingaswami, 1965 Sooch. et al., 1973). 

To evaluate the effectiveness of salt iodization programs, a large-scale study was organized in 1956 for the prevention of Himalayan endemic goiter in India. A follow-up study in 1962 showed a marked decrease in goiter prevalence, while uptake and excretion of urinary iodine had become normal, indicating a state of normal thyroid. 

The earliest and potentially most damaging result of iodine deficiency is neonatal hypothyroidism and cretinism. The wide prevalence of cretinism in the Himalayan and sub-Himalayan belt has been shown by several authors, starting from the turn of the last century. Studies of iodine metabolism in the Himalayan goiter zones of India and Nepal (Karmarkar et ai, 1974) showed (a) markedly increased avidity of the thyroid to radioiodine (b) reduced excretion of stable iodine in urine (c) extremely low levels of iodine in the drinking water (d) normal or reduced protein-bound iodine in plasma and (e) low inorganic iodide concentration in plasma. These findings are compatible with the hypothesis that environmental deficiency of iodine is the primary factor responsible for endemic goiter in these areas. 

Similar anomalies of thyroid function in neonates due to iodine deficiency have been reported in a severe endemic goiter area in Northern India... 

It is estimated that more than 200 million people are at risk of IDD in India. The number of persons suffering from goiter and other IDD is estimated to be above 71 million. The surveys conducted by central and state health directorates, ICMR, and medical institutes have clearly demonstrated that 263 out of the 324 districts in India (Figure 132.1) are endemic for IDD (Revised Policy Guidelines On National Iodine Deficiency Disorders Control Programme, 2006). 

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