Total goiter prevalence

Table 43.6 Change in total goiter prevalence between 1993 and 2003 by WHO region...

Until the 1990s, total goiter prevalence (TGP) in school-age children was the primary indicator for the assessment of functional consequences of iodine deficiency in the population (WHO et al., 2001). Thyroid size was traditionally determined by palpation, but the reliability of this method is limited by high inter-observer and intra-observer variations. The measurement of thyroid size by ultrasound has therefore been an important step in the detection of mild-to-moderate iodine deficiency. International reference values for normal thyroid size are now available from iodine-sufficient children (Zimmermann et al., 2004). Because TGP is not a sensitive indicator of recent changes in iodine status in the... 

Figure 48.1 Total goiter prevalence (TGP) in 1993 and 2003 and percent change in 2003 by WHO region. Percent change in TOP from 1993 to 2003.

Mandating periodic cohort surveys for tracking the disappearance of IDD by assessments of goiter, urinary iodine, neonatal total goiter prevalence and other relevant indicators. 

Mali is a landlocked country in West Africa, and is one of the poorest countries in the world. Iodine deficiency disorders (IDD) have been prevalent in several areas of the country, especially in the southern part. This chapter provides a historic overview of the changes in IDD over time, and of the various strategies that have been implemented to combat IDD. While the national total goiter rate was estimated to be 30% in 1974, a nationwide survey in 2005 found a total goiter rate of 8%, with 88% of the households using iodized salt. The latest figures indicate that Mali still suffers from iodine deficiency, and that efforts must continue in order to reach the goal of universal salt iodization. 

Endemic Goiter A total of 2395 schoolchildren in the above seven cities underwent thyroid palpation the prevalence of goiter among them is shown in Table 123.1. 

The most dramatic picture of neonatal hypothyroidism due to severe iodine deficiency has been observed in the Ubangi area in Zaire. In this area, the iodine intake is only 15 jLig/day, the prevalence of endemic goiter and cretinism are 76 % and 5 % of the total population respectively. In such extreme conditions, thyroid function in adults is definitely impaired with the classical picture of low serum concentration of T4 and elevated serum TSH andT3 2... 

Table 1. Historical prevalence of CNS damage by iodine deficiency in total population (a), of goiter among schoolchildren (b), and of "large" goiter causing unfitness for military service in 19-year-old men (c) (from ref 1 and 2).

In 12 endemic regions the prevalence was much higher-55,9%, goiter s grade III was 26,2% and nodules were 21%. Endemic cretenism of 3,5% was found in the centre of the endemic regions or about 6000 cretins totally (Fig.1). 

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