##article.abstract##
Background/Objective: There is an ongoing debate regarding the influence of subclinical hypothyroidism on body mass index. The objectives of the study were (i) to determine whether levels of thyroid stimulating hormone (TSH) are elevated in obese children, (ii)to compare the serum levels of triiodothyronine (T3 ) and thyroxine (T4 ) in obese with non-obese and (iii) to examine the association of subclinical hypothyroidism with lipoproteins and body mass index.
Methods: Fifty six obese children/adolescent girls aged 10.5±4.3years, BMI 31.2±2.2kg/m2 and apparently healthy children aged 11.2±5.2 years, BMI 21.0±2.1kg/m2 were evaluated. Serum T3 , T4 and TSH were measured using ELECSYS 1010 autoanalyzer while serum triglyceride, total cholesterol, LDL cholesterol, HDL cholesterol and glucose were measured using enzyme catalyzed colorimetric techniques.
Results: Subclinical hypothyroidism was observed in 10.7% of obese subjects. Significantly increase levels of T3 (p<0.02), TSH (p<0.01) and all lipoprotein fractions (p<0.001) except HDL cholesterol which was lower (p<0.001) were observed in obese than control subjects. TSH and triglyceride correlated positively with body mass index.
Conclusion: Subclinical hypothyroidism was present in 10.7% of obese children. TSH and triglyceride correlated positively with body mass index in childhood/adolescent obesity. There is need for this group of subjects to be evaluated for thyroid hormones so that those requiring therapy can be diagnosed and treated.
Keywords: Obesity, subclinical hypothyroidism, thyroid hormones, body mass index,lipoproteins.
Résumé
Il y a un débat continue sur l’influence de l’hypothyroïdisme subclinique sur l’indexe de masse corporelle. Les objectifs de cette étude étaient (i) de déterminer si les taux de stimulants d’hormones thyroïdiens (TSH) sont élevés chez les enfants obeses, (ii) de comparaitre les taux d’hormones thyroïdiens dans le sérum thiiodothyronine (T3 ) et thyroxine (T4 ) chez les obeses et non obeses et (ii) d’examiner l’association de l’hypothyroïdisme subclinique avec lipoprotéines et l’indexe de masse corporelle. Cinquante six enfants et adolescent filles obeses âgées de 10.5±4.3ans, IPC 31.2±2.2kg/m2 et les enfants apparemment sain âgées 11.2±5.2 ans, IPC 21.0±2.1kg/m2 étaient évaluées. Les taux de sérum T3 , T4 et TSH étaient mesures en utilisant l’auto analyseur ELECSYS 1010 cependant les taux de sérum triglycéride, cholestérol total, LDL cholestérol, cholestérol HDL et glucose étaient mesurés utilisant les techniques de colorimétriques catalysés par des enzymes. Hypothyroïdisme subclinique était observé chez 10.7% des sujets obese. Les taux significatifs augmentaient T3 (p<0.02), TSH (p<0.01) et toutes les fractions de lipoprotéines (p<0.001) exception cholestérol HDL qui était faible (p<0.001) étaient observé chez les sujets obeses que les sujets sains. TSH et triglycéride corrélaient positivement avec l’indexe de masse corporelle en obésité infantile et à l’adolescence. L’hypothyroïdisme subclinique était présent chez 10.7% des enfants obeses. Il est nécessaire pour ces sujets d’évaluer les hormones thyroïdiennes afin que ceux malades puissent être diagnostiqués et traités.
Correspondence: Emokpae MA, Department of Medical Laboratory Science, University of Benin, Benin City, Nigeria. Email: biodunemokpae@yahoo.com
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