Abstract

Background and Objectives: Hypothyroidism is one of the most important and preventable causes of mental retardation in newborns. The incidence of Congenital Hypothyroidism (CH) in Kerman province is considerably higher than the whole country.

Methodology: This study aimed to investigate the incidence and geographical distribution of CH by using Geographic Information System in Kerman province during 2011 - 2013. Three-year incidence rate of neonatal hypo thyroid disease was calculated and plotted on digital maps with the scale of 1/100000 using ArcGIS 0.9.2 software in Kerman province.

Result: In this study, 393 newborns with Congenital hypothyroidism who had been diagnosed through the three years (2011 - 2014) in Kerman province were investigated. Among this population, 225 cases were boys and 168 were girls. The incidence of three-years Congenital hypothyroidism was 1 in 230 live births, at the provincial level. The findings of this study showed that the incidence of Congenital hypothyroidism in Raver, Baft, Orzoeeyeh and Kuhbanan was higher than other cities in Kerman province (5.04 to 13.67 in 1000). There was no statistically significant correlation between sea level and the overall incidence of CH disease and only a weak correlation was seen between the average above sea level and incidence of CH in the female newborns (P = 0.116, r = 0.33).

Conclusion: In this study, it was showed that Raver, Baft, Orzoeeyeh and Kuhbanan cities had high incidence of disease, using the Geographic Information System. According to existing patterns, it seems that we should look for other factors such as socioeconomic status, parental consanguinity, genetic factors and also maternal nutritional deficiencies during pregnancy and more studies are needed in this regard.

Keywords: Neonatal Congenital Hypothyroidism; Geographic Information System; Kerman

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