Growth pattern of childhood thyrotoxicosis: longitudinal follow-up to final height.

OBJECTIVE

To study the growth pattern of children affected with thyrotoxicosis.

MATERIAL AND METHOD

A retrospective study of growth data of 40 patients with thyrotoxicosis diagnosed at prepuberty or at early puberty was conducted. All patients were evaluated for height and weight every 3-6 months. Height and weight were transformed to standard deviation score (SDS) to account for differences of age and sex.

RESULTS

At the time of diagnosis, the patients were slightly underweight for height (weight SDS -0.27 +/- 1.24, height SDS -0.06 +/- 1.26). After 1 year of treatment, the average weight gain of the patients was 4.9 +/- 3.1 kg, resulting in becoming relatively overweight for height (weight SDS +0. 32 +/- 1.42, height SDS +0.02 +/- 1.32). At the time of reaching their final height, the patients had an appropriate weight for height (weight SDS +0.06 +/- 0.21, height SDS -0.04 +/- 1.01). The average final height SDS of the patients was -0.04 +/- 1.01. This was at the average of the general population, but was +0.57 +/- 0.48 SDS or +2.85 +/- 1.0 cm greater than their target height (p < 0.01).

CONCLUSION

Growth of patients with thyrotoxicosis showed the same pattern as in the general population. The final height of thyrotoxicosis patients was averagely +0.57 SDS or +2.85 cm greater than their genetic potential. This could be from the result of secular trend in the general population rather than being the effect of thyrotoxicosis.