Subclinical hypothyroidism in obese children

Öz

Objective: Thyroid functions in obese children and ado­lescents were evaluated in order to determine subclinical and clinical hypothyroidism. Materials and methods: In this study, 85 obese (Body mass index >97th percentile) children, aged 2-14 years, as well as 47 healthy controls were enrolled. Levels of serum free triiodothyronine (fT3), free thyroxine (fT4) and thyroid-stimulating hormone (TSH) of the two groups were compared. Obese children with TSH level above 5.4 IU/ml were also analyzed for anti-thyroglobulin (anti Tg) and antiperoxidase antibodies (anti TPO) and thyroid ul­trasounds were performed. Results: Obese children showed higher serum concen­trations of TSH and fT3 than the controls but no significant difference in serum fT4 levels was found between the two groups (P=0.001). One child had high auto antibodies and 32 had high TSH levels. Of the latter, 29 children had normal thyroid ultrasound findings and three had nodules or thyroiditis but no enlargement of the thyroid gland. Conclusion: TSH and fT3 levels were found to be higher in obese children compared with non-obese children with no difference of fT4 levels between two groups.

Anahtar Kelimeler

• Body mass index, obesity, thyroid functions

Obez çocuklarda subklinik hipotiroidi

Öz

Amaç: Çocukluk çağı obezitesinde tiroid fonksiyonlarının değerlendirilmesi, subklinik-klinik hipotiroidinin saptan­ması amaçlanmıştır. Gereç ve yöntem: Çalışmamızda, 2-18 yaş arasında 85 obez, 47 obez olmayan hastanın, serbest triiyodotironin( sT3) ve tiroksin (sT4) ve tiroid stimülan hormon (TSH) dü­zeylerine bakıldı. Obez grupta, TSH düzeyi 5,4uIU/ml\'nin üzerinde saptanan hastaların, tiroid otoantikor düzeyleri ölçüldü ve tiroid ultrasonu yapılarak tiroid volümü hesap­landı. Bulgular: Obez hastaların sT3 ortalamaları ve TSH de­ğerleri, kontrol grubunun değerlerinde istatistiksel olarak anlamlı derecede yüksek bulunurken, sT4 ortalamala­rında iki grup arasında fark saptanmadı. TSH >5,4 IU/ ml olan hastalardan birinde otoantikor düzeylerinde yük­seklik saptandı. TSH >5,4 IU/ml olan 28 hastadan 25\'inin tiroid ultrasonu normal iken, kalan 3 hastada tiroidit veya nodül saptandı ancak tiroid büyümesi yoktu. Sonuç: Vücut kitle indeksi (BMI) yüksek hastalarda sT3 ve TSH düzeyi yüksek, sT4 ise normal saptanmıştır. TSH ve sT3 yüksekliği obesitenin bir sonucudur ve edinsel hi­potroidi ile ayırıcı tanısı yapılmalıdır.

Anahtar Kelimeler

• Beden kitle indeksi, obezite, tiroid fonksiyonları

Kaynakça

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