N-terminal pro-B-type natriuretic peptide and insulin resistance in overweight and obese subjects

Several studies have been conducted to investigate B-type natriuretic peptide (BNP) levels in different obese populations. However, in these studies BNP levels were lower in obese population with an unclear mechanism which has not been explained yet. We sought to investigate the relationship among plasma NT-proBNP levels, obesity and insulin resistance in subjects with no known heart disease. The study population consists of two groups. Subjects with a body mass indexs (BMI) of ≤25 kg/m2 were classified as lean group (LG, n=30), BMI of >25 kg/m2 were classified as overweight and obese group (OG, n=78). Severe hypertension, heart failure, ischemic heart disease, renal or hepatic insufficiency, age >65, pregnancy and malignancy were excluded. There was a negative correlation between NT-proBNP and weight (r=-0.379, p=0.004) and BMI (r=-0.286, p=0.030) in LG, but there was no such reverse correlation between NT-proBNP and BMI (r=-0.057, p=0.463) in OG. We performed multivariable logistic regression analyses to examine predictors of obesity levels. There were not any significant relation between these predictors and obesity. Insulin levels had a strong association with obesity level however this association was still insignificant (p=0.054). In LG group, there was a negative correlation between NT-proBNP and BMI. There was no correlation between NT-proBNP and homeostatic model assessment (HOMA) and insulin levels (r=-0.035, p=0.789) in LG group, but there was a statistically significant negative correlation between BNP and HOMA (r=-0.219, p=0.009) and insulin levels (r=-0.252, p=0.002) in OG group. Race and ethnicity may contribute this association. Obez ve fazla kilolu kisilerde N-terminal pro-B-tip natriuretik peptid ve insulin direnci Farkli obez populasyonlarda B-tip natriuretik peptid (BNP) seviyelerini arastiran bazi calismalar yapilmistir. Henuz tam aciklanamayan bir mekanizma ile obezlerde BNP duzeyleri siklikla dusuk olarak saptanmaktadir. Bilinen kalp hastaligi olmayan bireylerde plazma NT-proBNP seviyeleri, obezite ve insulin direnci arasindaki iliskiyi arastirmayi amacladik. Calisma populasyonumuz iki gruptan olusmaktaydi. Vucut kitle indeksi (VKI) ≤25 kg/m2 olanlar zayif grubuna (LG, n=30), >25 kg/m2 olanlar ise fazla kilolu ve obez grubuna (OG, n=78) alindi. Ciddi hipertansiyonu, kalp yetmezligi, iskemik kalp hastaligi, bobrek veya karaciger yetmezligi, malignitesi olan hastalar, gebeler ve 65 yas ustu hastalar calismaya alinmadi. Zayif hastalarin grubunda NT-proBNP ile kilo (r=-0,379, p=0,004) ve VKI (r=-0,286, p=0,030) arasinda negatif bir iliski varken, obez grupta NT-proBNP ve VKI arasinda boyle bir ters korelasyon saptanmadi. Obezite seviyelerinin belirteclerini saptamak icin cok degiskenli lojistik regresyon analizleri yaptik. Bu belirtecler ile obezite arasinda anlamli iliski saptanmadi. Insulin seviyelerinin obezite ile guclu bir iliskisi vardi ancak yine de bu iliski istatistiksel anlamlilik duzeylerine ulasamiyordu (p=0,054). Zayif hasta grubunda NT-proBNP ve VKI arasinda ters korelasyon vardi. Ayni grupta NT-proBNP ve homeastatik modelde degerlendirme (HOMA) ve insulin seviyeleri (r=-0,035, p=0,789) arasinda korelasyon yoktu, ancak obez grupta BNP ve HOMA (r=-0,219, p=0,009) ve insulin seviyeleri (r=-0,252, p=0,002) arasinda istatistiksel olarak anlamli ters iliski vardi. Irk ve etnik koken bu farkliliga katkida bulunuyor olabilir. J. Exp. Clin. Med., 2012; 29:179-182