Levothyroxine supplementation for obesity-associated thyroid dysfunction in children: a prospective, randomized, case control study

Abstract

Introduction: The specific treatment of thyroid dysfunction associated with simple obesity (SO) in children is controversial. Material and methods: Fifty-one children having SO (BMI ≥ 2 Z-score) aged 6-12 years with elevation of serum thyroid stimulating hormone (TSH) (4-10 mIU/l) with or without alterations in serum triiodothyronine (T3) or thyroxine (T4) were randomised to receive either routine weight management intervention (group 1, n = 25) or additional low dose levothyroxine (~0.5 μg/kg/day) (group 2, n = 26) and followed up at 3-month intervals for 6 months. Results: The mean BMI Z-scores decreased in both groups from baseline to 3 and 6-month time points (group 1, 3.69 ±1.31 to 3.24 ±1.45 to 2.84 ±1.46, p = 0.03 and group 2, 4.31 ±2.11 to 4.08 ±1.92 to 3.50 ±1.93, p = 0.02). However, the decrease was similar in the 2 groups (-0.80 ±0.77 vs-0.97 ±0.69, p = 0.19). All children had isolated hyperthyrotropinemia. The mean TSH levels decreased from baseline to endpoint in group 1 (5.51 ±1.0 to 4.14 ±1.0 to 4.04 ±1.1 mIU/l, mean change-1.44 ±1.20, p = 0.001) and in group 2 (5.89 ±1.10 to 5.89 ±1.10 to 3.89 ±1.48 mIU/l, mean change-1.93 ±1.15, p = 0.001). The decrease in TSH levels was also similar in the 2 groups (p = 0.69). TSH normalized in 48% and 57.6% in group 1 and group 2 respectively. The decrease in total cholesterol and triglycerides was also similar in the 2 groups. Conclusions: Addition of levothyroxine to weight management interventions has no beneficial effect on BMI reduction as well as parameters of lipid and thyroid profiles, and should not be prescribed to children with obesity associated thyroid dysfunction.

Juvenile hypothyroidism: A clinical perspective from Eastern India

“…[ 16 ] Treatment of obesity-associated subclinical hypothyroidism has almost no influence on the body weight and lipid profile. [ 17 ]…”

Thyroid hormone axis and anthropometric recovery of children/adolescents with overweight/obesity: a scoping review

“…Table 1 summarizes the characteristics of the studies included in the analysis. There are studies performed with subjects from Italy (14,16,17), France (8,15), Israel (11,22), Turkey (12,18), Germany (13,19,20), the Netherlands (9), Swiss (10), United States (21), and India (23).…”

“…In 5 studies, a psychological intervention was added to the nutritional plus exercise intervention (10,13,14,19,20). One study performed the 3 interventions plus levothyroxine supplementation (23).…”

“…These results show that the most common status of thyroid hormones falls into normal levels. TSH levels at baseline were not reported in 5 studies (8,9,12,20,21) while 2 studies selected only individuals with hyperthyrotropinemia (22,23). Among the remaining 9 studies, the mean levels were normal in 6 studies (10,11,15–19), although some of these studies found mean values in the high normal range and highlighted the presence of elevated levels in variable percentages of their cohorts, namely 1.9% (10), 28.6% (11), 13.1% (15), 17.2% (16), and 3.2% (17).…”

Levothyroxine in Children

“…Obesity is associated with hypothyroidism (especially the subclinical form) in children, as described above. A 6-month, randomised trial in 51 obese children with TSH 4-10 mIU/L (with or without abnormalities of other thyroid hormones) showed that administration of LT4 vs. no additional treatment, alongside weight loss interventions, had no significant effect on BMI or lipid abnormalities [66]. A similar study, where LT4 was or was not added to a behavioural intervention for obesity, reported similar results [67].…”