Obesity and thyrotropinemia

To study the relation between body mass index (BMI) and TSH in euthyroid and subclinical hypothyroid obese children and compared serum TSH level among obese and overweight children.

Fifty consecutive children (aged 2-18 yr) presenting for obesity were studied. All cases with TSH > 10, low T3/T4, organic and syndromic obesity were excluded. Patients were divided into Group 1: Overweight (n=20) (BMI between 85(th) to 95(th) centile) and Group 2: Obesity (n=30) (BMI > 95(th) centile). Fisher's exact test, Mann-Whitney U test and Pearson's correlation were used for statistical analysis. P value < 0.05 was considered significant.

Elevated TSH level (between 4.5-10 mIU/L) with normal T3, T4 was seen in 4/20 overweight and 9/30 of obese children (P=0.5219). The mean TSH was comparable in both the groups (3.22 +/- 3.1 mIU/L vs. 3.63 +/- 2.2 mIU/L, P=0.3491). Overall TSH showed no correlation with BMI (r= 0.0014, P=0.9924).

The preliminary data did not show any relation between severity of obesity and TSH level. Further large scale data from population are required to confirm these findings.