[Endemic goiter in Argentina. Epidemiologic studies before (1968) and during (1986) prophylaxis with iodized salt in the city of Buenos Aires].

An epidemiological survey on goiter was conducted in Buenos Aires, on 3882 schoolchildren, a randomized sample of 160,026 children of public schools, before establishing prophylactic measures in 1968. With an estimated error of 5% the result was 14.8% of goiter prevalence. This figure qualified Buenos Aires as an endemic area and was, therefore, included in the National Programme to Combat Endemic Goiter, through iodized salt (proportion 1:30,000 of salt). Schools were qualified according to their social level in high, middle and low; the prevalence of goiter was 6.8%, 12.2% and 26.4%, respectively. The prevalence was also higher in older ages. In 1986, using the same randomized sample, a second survey was conducted, after 18 years of prophylaxis. Goiter prevalence was 8.5%. Goiter in the low social class was about the same as in the middle class. In randomized samples of 49 urines, iodine concentration was determined yielding an average of 139.6 micrograms/g creatinine (median 120.9 micrograms/g creatinine). Urinary iodine level in 14 children with goiter was 146.1 micrograms/g creatinine and in 12 without goiter was 171.4 micrograms/g. There was no statistical difference between these three groups. Variations in radioiodine uptake, urinary iodine, plasma inorganic iodine levels, and water iodine are discussed.