Subklinik Hipotiroidisi Olan Obez Çocuk ve Adölesanlarda Lipid Metabolizması Anormallikleri

Öz

Giriş: Subklinik hipotiroidi (SH); serum serbest T4 (sT4) düzeylerinin normal sınırlarda ve tiroid stimülan hormon (TSH) düzeylerinin yaşa göre referans düzeylerinin üzerinde olduğu bir tablodur. Obez bireylerde vücut kitle indeksindeki artış ile birlikte serum TSH düzeylerinin arttığı; böylece obez bireylerde SH sıklığının yüksek olduğu bildirilmektedir. Hipotiroidi ve obezite sekonder dislipideminin ana sebeplerindendir. Bu çalışmada; fazla kilolu/obez çocuk ve adölesanlarda; SH sıklığı ve SH’nin lipid metabolizması anormallikleri ile ilişkisi araştırılmıştır.
Gereç ve Yöntem: Fazla kilolu/obez 291 çocuk ve adölesanın (169 kız, 122 erkek) klinik bulguları ve laboratuvar sonuçları geriye dönük olarak değerlendirildi. Lipid ve lipoprotein düzeyleri yaşa ve cinse göre referans değerleri ile karşılaştırılarak; düşük, normal ve yüksek olarak kaydedildi. Serum sT4 düzeyleri normal ve TSH düzeyleri: 4,5-10 mIU/ml olan ve sodyum L-throxin tedavisi almayan hastalar SH grubunu (n=53), normal serum T4 ve TSH düzeyleri olan hastalar kontrol grubunu oluşturdu (n=238). Bu iki grup lipid metabolizması anormallikleri açısından
karşılaştırıldı. 
Bulgular: Tüm çalışma grubunda SH sıklığı %18,2 idi. Yaşa göre referans değerleri ile karşılaştırıldığında; tüm çalışma grubunda, SH grubu ve SH olmayan
grupta; median total kolesterol ve LDL-K düzeyleri sınırda yüksek, median  TG düzeyleri yüksek, median HDL-K düzeyleri normal-yüksek ve median TG/ HDL>2 idi. SH grubunda SH olmayanlara göre; serum total kolesterol düzeyleri, hipertrigliseridemi sıklığı ve TG/HDL-K oranı >2 olan hastaların sıklığı daha yüksekti (p<0,05). Serum TSH düzeyleri; TG ile pozitif korele idi (r=0,13, p<0,05). 

Sonuç: Fazla kilolu/obez çocuk ve adölesanlarda yüksek SH sıklığı bulunmaktadır. Obez hastalarda dislipidemi olduğu; SH varlığında bu durumun daha belirginleştiği ve SH’nin atherojenik lipid profili gelişmesine katkıda bulunduğu anlaşılmıştır. Bu Bulgular obez hastaların kilo vermelerinin hem SH’nin hem de lipid metabolizması anormalliklerinin düzelmesi açısından da önemli olduğunu düşündürmüştü

Anahtar Kelimeler

• subklinik hipotiroidi,
• obez,
• çocuk

Evaluation of the Relationship Between Subclinical Hypothyroidism and Lipid Metabolism Abnormalities and Non- Alcoholic Fatty Liver Disease in Obese Children and Adolescents

Abstract

Introduction: Subclinical hypothyroidism (SH); is a condition that serum free T4 (sT4) levels are normal and thyroid stimulating hormone (TSH) levels are above the reference levels by age. It is reported that the increase in body mass index (BMI) in overweight and obese children and adolescents leads to an increase in serum TSH levels and the frequency of SH in these children. It is also suggested frequency of SH and the relationship between SH with lipid metabolism abnormalities and NAFLD were investigated in overweight and obese children and adolescents. Materials and Methods: Clinical, laboratory and imaging results of 291 overweight and obese children and adolescent patients (169 girls, 122 boys) were analyzed retrospectively. Patients with normal serum sT4 levels and TSH levels between 4,5-10 mIU / ml (SH group) (n=53) and patients with normal serum T4 and TSH levels (control group) (n=238), were compared in terms of liver function tests, lipid parameters and presence of NAFLD. Results: The frequency of SH was 18,2% (n=53), and the frequency of NAFLD was in 47,7% (n=139) in all study group. Serum total cholesterol levels were higher in the SH group (p<0,05) and the frequency of NAFLD (n=23, 43,3%) was not different from patients without SH (n=122, 48,7%) (p>0,05). Serum TSH levels correlated positively with triglyceride (r=0,1, p<0,05) and alanine aminotransferase levels (r=0,135, p<0,05). The frequency (n=34) of patients with TG / HDL-K ratio>2 was higher than those without SH (p<0,05). Conclusions: The frequency of SH is high in obese children and adolescent patients. Atherogenic lipid metabolism disorders are more common in patients with SH. The presence of SH in obese children and adolescents does not affect the frequency of NAFLD.

Kaynakça

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