Homojen klirens ve PTA / MgCl2 çöktürmeli yöntemleri ile saptanan HDL kolesterol düzeylerinin karşılaştırılması

Koroner atheroskleroz riskinin belirlenmesinde koruyucu bir faktör olarak değerlendirilen HDL-C analizinde homojen yöntemler yaygın olarak kullanılmaktadır. Bu çalışmada, 100 serum örneğinde HDL-C düzeyleri homojen klirens ve PTA/MgCl2 çöktürmeli yöntemleri ile Ortalama Ortalamanın Standart Hatası (XOSH) olarak sırasıyla, 501 ve 491 olarak saptanmıştır. Ortalamalar arasındaki fark (homojen-heterojen) anlamsızdır (bias : 1.2 1.0, p0.05). İki yöntemle saptanan HDL-C düzeyleri arasında pozitif bir korelasyon bulunmuştur (r: 0.62, p0.001). Klirens yöntemi için regresyon eşitliği y=0.55x+23.1 olarak bulunmuştur. Homojen klirens ve heterojen HDL-C ölçüm yöntemleri arasındaki bias ile trigliserit düzeyleri arasında negatif korelasyon saptanmıştır (r: -0.203, p0.05). Total kolesterol ve LDL-C düzeyleri bias ile ilişkili bulunmamıştır. Sonuçlarımıza göre, homojen klirens yöntemi ile saptanan HDL-C düzeyleri, çöktürmeli PTA/MgCl2 yönteminden farksız bulunmuştur. Bias'ın trigliserit ile negatif korelasyonu, çöktürmeli yöntemin klirens yöntemine göre örneğin trigliserit içeriğinden daha fazla etkilenmiş olabileceğini düşündürmektedir. Yöntemlerin analitik özgüllüğünü etkileyebilecek diğer faktörlerin araştırılmasına gerek duyulmaktadır.

Comparison of HDL cholesterol levels determined by homogenous clearence and PTA / MgCl2 precipitation methods

HDL-C, a protective factor for coronary artery disease risk, has been widely determined with homogenous methods. In this study, HDL-C concentrations determined with homogenous clearence and PTA/MgCl2 precipitation methods in 100 sera samples were (mean SEM) 501 and 491, respectively. Difference between means was not significant (homogenous-heterogen) (bias:1.21.0, p0.05). Results obtained by homogenous clearence and PTA/MgCl2 precipitation methods were correlated positively (r:0.62, p0.001). Regression equation for clearence method was y= 0.55x+23.1. A negative correlation was found between the bias and triglycerides concentration of the samples (r: -0.203, p0.05). Total cholesterol and LDL-C levels were not correlated with the bias. According to our results, HDL-C levels determined with homogenous clearence method were not different from PTA/MgCl2 precipitation method. The negative correlation between the bias and the triglyceride concentrations may indicate that precipitation method could be affected more than the clearence method by the triglyceride content of the samples. Further investigation is necessary to determine other factors that may affect analytical specificity of the methods.

Kaynakça

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