Effect of Obesity on Endothelial Function and Subclinical Atherosclerosis in Children

Abstract

We aimed to measure flow-mediated dilation (FMD), carotid intima-media thickness (cIMT), and to evaluate the effects of waist circumference (WC), and body mass index Z (BMI-Z) score on these parameters in obese children. This case-control cross-sectional study included 70 obese and 40 non-obese children aged 7-14 years who presented with various complaints and had no concomitant diseases. FMD and cIMT were measured in all subjects and correlated with anthropometric and biochemical factors. WC, BMI-Z score, systolic and diastolic blood pressure (BP), triglyceride (TG) and insulin concentrations, and homeostatic model assessment (HOMA) index were significantly higher, whereas high density lipoprotein (HDL) -cholesterol concentration was significantly lower in the obese than in the non-obese group. FMD values were significantly lower, whereas cIMT values were significantly higher in obese than in non-obese subjects. FMD negatively correlated with WC, BMI-Z score, serum insulin level, HOMA, systolic BP, triglyceride but positively with HDL-cholesterol. cIMT positively correlated with WC, BMI-Z score, serum insulin level, HOMA, systolic BP, triglyceride but negatively with HDL-cholesterol. Increased WC, BMI-Z score, serum insulin level, HOMA, systolic BP, triglyceride and decreased HDL-cholesterol in obese children contribute to endothelial dysfunction and early subclinical atherosclerosis compared to their normal weight peers.

Keywords

• Children, carotid intima-media thickness, flow mediated- dilatation, obesity

Effect of Obesity on Endothelial Function and Subclinical Atherosclerosis in Children

Öz

Obez çocuklarda akım aracılı dilatasyonu (AAD), karotis intima-media kalınlığını (kİMK) ölçmeyi ve bel çevresi (BÇ) ile beden-kitle indeksi Z (BKİ-Z) skorunun bu parametrelere etkisini değerlendirmeyi amaçladık. Bu vaka kontrollü karşılaştırmalı kesitsel çalışma 7-14 yaşlarında, değişik şikayetlerle pediatri polikliniğine gelen ve eşlik eden hastalığı olmayan, 70 obez ve 40 obez olmayan çocuğu kapsamaktaydı. AAD ve kİMK tüm bireylerde ölçüldü ve antropometrik, biyokimyasal faktörlerle ilişkisi araştırıldı. Obez grupta yüksek dansiteli lipoprotein (YYL) kolesterol konsantrasyonu obez olmayan gruptan belirgin derecede düşük iken; BÇ, BKİ-Z skoru, sistolik ve diyastolik kan basıncı (KB), trigliserit (TG), insülin konsantrasyonları ve HOMA (homeostatic model assessment) indeksi belirgin derecede yüksekti. Obez grupta kİMK değerleri obez olmayan gruptan belirgin derecede yüksek iken, AAD değerleri belirgin derecede düşüktü. AAD değerleri; BÇ, BKİ-Z skoru, serum insulin seviyesi, HOMA, sistolik KB, TG ile negatif; HDL kolesterol ile pozitif ilişkiliydi. kİMK değerleri; BÇ, BKİ-Z skoru, serum insulin seviyesi, HOMA, sistolik KB, TG ile pozitif; HDL kolesterol ile negatif ilişkiliydi. Normal kilolu yaşıtlarıyla karşılaştırıldığında, obez çocuklarda, artmış BÇ, BKİ-Z skoru, serum insulin seviyesi, HOMA, sistolik KB, TG ve azalmış HDL kolesterol, endotel disfonksiyonu ve erken subklinik ateroskleroza katkıda bulunmaktadır

Anahtar Kelimeler

• Çocuklar, karotis intima-media kalınlığı, akım aracılı dilatasyon, obezite

Kaynakça

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