Abstract
Background: Serum thyroid stimulating hormone (TSH) levels are frequently elevated in obese children and are most likely to be associated with insulin resistance. However, clinical relevance of this association remains unclear.
Objectives: To assess the prevalence of hyperthyrotropinemia; to analyze the relationship between TSH and homeostasis model assessment – insulin resistance (HOMA-IR); and to verify whether TSH levels and HOMA-IR vary with weight loss in obese children.
Subjects and Methods: Retrospective longitudinal study with data from baseline and 1 year after lifestyle intervention in a pediatric obese group (344 children were recruited and 100 among them completed follow-up). For postintervention analysis, three groups were considered according to body mass index-standard deviation score (BMI-SDS) variations: ≤–0.5 (significant weight loss); 0.5–0 (weight loss); and >0 (weight gain). Statistical analysis was performed using SPSS 19.0®.
Results: The prevalence of increased TSH levels was 9.3%. At baseline TSH (p=0.007), fT4 (p=0.006), and HOMA-IR (p<0.001) were positively correlated to BMI-SDS (n=344). Weight reduction was verified in 67 out of 100 cases but significant loss was present in only 21 cases. Decreases in both TSH and BMI-SDS were independently associated with decreases in HOMA-IR (p=0.005 and p=0.016, respectively). There was no correlation between TSH and BMI-SDS variation. Significant decreases in the HOMA-IR (p=0.006) were only achieved in the significant weight loss group.
Conclusions: The prevalence of hyperthyrotropinemia was lower than previously reported. However, cutoff values were adjusted to pubertal stage, suggesting an over report in other studies. Insulin resistance and TSH were positively correlated, independent of body status. Although weight loss was not associated with TSH variation, a decrease in TSH levels was independently associated with decreases in HOMA-IR.
References
1. Pacifico L, Anannia C, Ferraro F, Andreoli GM, Chiesa C. Thyroid function in childhood obesity and metabolic comorbidity. Clin Chim Acta 2012;413:396–405.10.1016/j.cca.2011.11.013Search in Google Scholar PubMed
2. Kithara CM, Platz EA, Ladenson PW, Mondul AM, González AB. Body fatness and markers of thyroid function among US men and women. PLos One 2012;7:e34979.10.1371/journal.pone.0034979Search in Google Scholar PubMed PubMed Central
3. Reinehr T. Thyroid function in the nutritionally obese child and adolescent. Curr Opin Pediatr 2011;23:415–20.10.1097/MOP.0b013e328344c393Search in Google Scholar PubMed
4. Shalitin S, Yackobovitch-Gavan M, Phillip M. Prevalence of thyroid dysfunction in obese children and adolescents before and after weight reduction and its relation to other metabolic parameters. Horm Res 2009;71:155–61.10.1159/000197872Search in Google Scholar PubMed
5. Grandone A, Santoro N, Coppola F, Calabrò P, Perrone L, et al. Thyroid function derangement and childhood obesity: an Italian experience. BMC Endocr Disorders 2010;10:1–7.10.1186/1472-6823-10-8Search in Google Scholar PubMed PubMed Central
6. Reinehr T. Obesity and thyroid function. Mol Cell Biol 2010;316:165–71.10.1016/j.mce.2009.06.005Search in Google Scholar PubMed
7. D’Adamo E, De Leonibus C, Giannini C, Corazzini V, De Remigis A, et al. Thyroid dysfunction in obese pre-pubertal children: oxidative stress as a potential pathogenetic mechanism. Free Radic Res 2012;46:303–9.10.3109/10715762.2011.653967Search in Google Scholar PubMed
8. Longhi S, Radetti G. Thyroid function and obesity. J Clin Res Pediatr Endocrinol 2013;5:40–4.Search in Google Scholar
9. Wabitsch M, Reinehr T. Endocrine disorders that follow obesity in childhood and adolescence. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2013;56:500–3.10.1007/s00103-012-1642-9Search in Google Scholar PubMed
10. Álvarez-Castro P, Sangiao-Alvarellos S, Brandón-Sandá I, Cordido F. Endocrine function in obesity. Endocrinol Nutr 2011;58:422–32.10.1016/j.endonu.2011.05.015Search in Google Scholar PubMed
11. Reinehr T, Sousa G, Andler W. Hyperthyrotropinemia in obese children is reversible after weight loss and is not related to lipids. J Clin Endocrinol Metab 2006;91:3088–91.10.1210/jc.2006-0095Search in Google Scholar PubMed
12. Aypak C, Türedi O, Yüce A, Görpelioğlu S. Thyroid-stimulating hormone (TSH) level in nutritionally obese children and metabolic co-morbidity. J Pediatr Endocrinol Metab 2013;26:703–8.10.1515/jpem-2012-0384Search in Google Scholar PubMed
13. Marras V, Casini MR, Pilia D, Civolani P, Porcu M, et al. Thyroid function in obese children and adolescents. Horm Res Paediatr 2010;73:193–7.10.1159/000284361Search in Google Scholar PubMed
14. Reinehr T, Isa A, de Sousa G, Dieffenbach R, Andler W. Thyroid hormones and their relation to weight status. Horm Res 2008;70:51–7.10.1159/000129678Search in Google Scholar PubMed
15. Dall’Asta C, Paganelli M, Morabito A, Vedani P, Barbieri M, et al. Weight loss through gastric banding: effects on TSH and thyroid hormones in obese subjects with normal thyroid function. Nature Pub Group 2010;18:854–7.10.1038/oby.2009.320Search in Google Scholar PubMed
16. Aeberli I, Jung A, Murer SB, Wildhaber J, Whildhaber-Brooks J, et al. During rapid weight loss in obese children, reductions in TSH predict improvements in insulin sensitivity independent of changes in body weight or fat. J Clin Endocrinol Metab 2010;95:5412–8.10.1210/jc.2010-1169Search in Google Scholar PubMed
17. Reinehr T, Andler W. Thyroid hormones before and after weight loss in obesity. Arch Dis Child 2002;87:320–3.10.1136/adc.87.4.320Search in Google Scholar PubMed PubMed Central
18. Ruhla S, Weickert M, Arafat AM, Osterhoff M, Isken F, et al. A high normal TSH is associated with the metabolic syndrome. Clin Endocr 2010;72:696–701.10.1111/j.1365-2265.2009.03698.xSearch in Google Scholar PubMed
19. WHO. Physical status: the use and interpretation of anthropometry. In: WHO, editor. Geneva: WHO, 1995.Search in Google Scholar
20. Marfell-Jones M, Olds T, Stewart A, Carter JE. International standards for anthropometric assessment. Potchefstroom: ISAK, 2006.Search in Google Scholar
21. Kuczmarski RJ, Ogden CL, Guo SS, Grummer-Strawn LM, Flegal KM, et al. 2000 CDC growth charts for the United States: methods and development. National Center for Health Statistics. Vital Health Stat 2002;11:1–190.Search in Google Scholar
22. Mathews DR, Hosker JP, Rudenski AS, Naylor BA, Treacher DF, et al. Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man. Diabetologia 1985;28:412–9.10.1007/BF00280883Search in Google Scholar PubMed
23. Reinehr T, Andler W. Changes in atherogenic risk-factor profile according to the degree of overweight. Arch Dis Child 2004;89:419–22.10.1136/adc.2003.028803Search in Google Scholar PubMed PubMed Central
24. Lem AJ, Rijke YB, van Toor H, Ridder MA, Vissen TJ, et al. Serum thyroid hormone levels in healthy children from birth to adulthood and in short children born small for gestational age. J Clin Endocrinol Metab 2012;97:3170–8.10.1210/jc.2012-1759Search in Google Scholar PubMed
25. Verburg FA, Kirchgässner C, Hebestreit H, Steigerwald U, Lentjes EG, et al. Reference ranges for analytes of thyroid function in children. Horm Met Res 2011;43:422–6.10.1055/s-0031-1275326Search in Google Scholar PubMed
26. Pearce EN. Thyroid hormone and obesity. Curr Opin Endocrinol Diabetes Obes 2012;19:408–13.10.1097/MED.0b013e328355cd6cSearch in Google Scholar PubMed
27. Nader NS, Bahn RS, Johnson MD, Weaver AL, Singh R, et al. Relationships between thyroid function and lipid status or insulin resistance in a pediatric population. Thyroid 2010;20:1333–9.10.1089/thy.2010.0180Search in Google Scholar PubMed
28. Duntas LH, Biondi B. The interconnections between obesity, thyroid function, and autoimmunity: the multifold role of leptin. Thyroid 2013;23:646–53.10.1089/thy.2011.0499Search in Google Scholar PubMed
29. Brufani C, Manco M, Nobili V, Fintini D, Barbetti F, et al. Thyroid function tests in obese prepubertal children: correlations with insulin sensitivity and body fat distribution. Horm Res Paediatr 2012;78:100–5.10.1159/000341363Search in Google Scholar PubMed
30. Wolters B, Lass N, Reinehr T. TSH and free triiodothyronine concentrations are associated with weight loss in a lifestyle intervention and weight regain afterwards in obese children. Eur J Endocrionol 2013;168:323–9.10.1530/EJE-12-0981Search in Google Scholar PubMed
31. Soriguer F, Valdes S, Morcillo S, Esteva I, Almaraz M, et al. Thyroid hormone levels predict the changes in body weight: a prospective study. Eur J Clin Invest 2011;41:1202–9.10.1111/j.1365-2362.2011.02526.xSearch in Google Scholar PubMed
32. Ambrosi B, Masserini B, Iorio L, Delnevo A, Malavazos AE, et al. Relationship of thyroid function with body mass índex and insulin-resistance in euthyroid obese subjects. J Endocrinol Invest 2010;33:640–3.10.1007/BF03346663Search in Google Scholar PubMed
33. Tarcin O, Abanonu GB, Yazici D, Tarcin O. Association of metabolic syndrome parameters with TT3 and fT3/fT4 ratio in obese Turkish population. Metab Syndr Relat Disord 2012;10:137–42.10.1089/met.2011.0098Search in Google Scholar PubMed
34. Katzeff HL, Selgrad C. Maintenance of thyroid hormone production during exercise-induced weight loss. Am J Physiol 1991;261:E382–8.10.1152/ajpendo.1991.261.3.E382Search in Google Scholar PubMed
©2015 by De Gruyter