Effect of levo-thyroxine treatment on weight and body mass index in children with acquired hypothyroidism.
OBJECTIVE
To determine whether normalization of thyroid-stimulating hormone (TSH) in children with acquired hypothyroidism is associated with a decrease in weight or body mass index (BMI).


METHODS
We retrospectively identified 68 subjects with acquired hypothyroidism who were seen at least once in our center in follow-up between 1995 and 2006.


RESULTS
Treatment with levo-thyroxine decreased the mean TSH level from 147 microU/mL initially to 5.0 microU/mL at the second visit 4.4 months later. This was not associated with a significant change in weight or BMI. Of the 68 subjects, 31% lost weight by the second visit (mean 2.3 kg). The mean initial TSH level of this group was 349 microU/mL. Thirty of the 68 children had at least 2 years of follow-up, and 19/68 had at least 4 years of follow-up. Over those intervals, weight and BMI percentiles and z scores did not change significantly from baseline values.


CONCLUSIONS
Most children treated for acquired hypothyroidism exhibited little short-term or long-term change in weight or BMI despite near-normalization of TSH. Those children who lost weight tended to have severe hypothyroidism and to have only a small weight loss. Consequently, practitioners should not expect significant decreases in weight after treatment in most children with hypothyroidism.
D000293:Adolescent; D015992:Body Mass Index; D001835:Body Weight / Q000187:drug effects*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D008297:Male; D009765:Obesity / Q000097:blood; D050177:Overweight / Q000097:blood; D012189:Retrospective Studies; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000627:therapeutic use*; D015431:Weight Loss
D013972:Thyrotropin; D013974:Thyroxine