Geen jodiumdeficiëntie of endemisch struma onder 6-18-jarige schoolkinderen in de regio's Doetinchem en Amsterdam

To determine the prevalence of iodine deficiency in schoolchildren.

Design

Cross-sectional survey.

Method

In 1995/96, thyroid size was determined in schoolchildren aged 6-18 years old from the eastern part of the Netherlands (Doetinchem region; an endemic goitre region, in 1985/86) and the western part (Amsterdam region; previously no endemic goitre). This was based on inspection and palpation of the neck and echographic measurement of the thyroid volume. The dietary iodine intake was also established using questionnaires, and the iodine concentration in urine samples was measured according to the Sandell-Kolthoff reaction.

Results

In total, 937 schoolchildren were studied (390 in Doetinchem and 547 in Amsterdam): of the children approached, 85-89 of primary school children and 60 of children at secondary school consented to participate. Both regions were similar with respect to median urinary iodine excretion (15.7 and 15.3 μg/dl, NS), goitre prevalence by inspection and palpation (0.8 and 2.6, p = 0.08), and thyroid volumes by ultrasound. From the dietary habits, we calculated a mean daily iodine intake of 171 μg in boys and 143 μg in girls, which correlates closely with the measured median urinary iodine of 16.7 μg/dl in boys and 14.5 μg/dl in girls. Thyroid volume increased with age. Girls had a larger thyroid volume at 12-13 years of age, but from 14 years of age onwards thyroid volume was larger in boys.

Conclusions

Iodine deficiency disorders did not exist. Bread consumption was the main source of dietary iodine. Puberty was associated with a marked increase in thyroid volume.