Evaluation Of The Effect Of Triglyceride Concentrations On Direct Ldl Cholesterol Levels

Year 2016, Volume: 8 Issue: 3, 107 - 114, 27.11.2016

Kübranur Ünal

Abstract

Objectives: Non-HDL cholesterol has been accepted as an alternative marker to LDL cholesterol in patients with high triglyceride levels in recent years. In this study, we aimed to investigate the effect of triglyceride concentrations on direct LDL-C determination method in comparison with non-HDL-C cholesterol used as an independent variable.

Materials and Methods: Samples were collected from patients who admitted to Ankara Numune Training and Research Hospital Biochemistry Laboratory for analysis of lipid profile during January-June 2012. The results were categorized as 7 groups according to triglyceride levels. 1. Group 0-200 mg / dl (n = 28, 56.2 + 11.8 years), 2 Group 200-400 mg / dl (n = 30, 54.2 ± 10.7 years), 3. Group 400-450 mg /dl (n = 52, 55.7 ± 10.9 years), 4.Group 450 -500 mg / dl (n = 27, 55.5 ± 10.6 years); 5.Group 500-600 mg / dl (n = 25, 56.5 ±11.3 years); 6.Group 600-700 mg / dl (n = 26, 56.8 ± 11.8 years); 7.Group >700 mg / dl (n = 34, 56.6 ± 11.1 years), respectively. Friedewald calculation and direct measurement of LDL-C levels were performed according to trygliceride levels.
Results: Correlation of each group between direct LDL-C and non-HDL-C; 1,Group (p < 0.001, r = 0.928), 2. Group (p < 0.001, r: 0.935 :); 3. Group (p < 0.001, r =0.925); 4. Group (p < 0.001, r = 0.865); 5.Group (p < 0.001, r = 0.895); 6.Group (p < 0.001, r = 0.835), 7.Group (p = 0 , 117, r:-0,251), respectively.

Conclusion: LDL-C concentrations can not be calculated using Friedewald formula when TG concentrations are higher than 400 mg/dL. In this situation LDL-C levels are determined using direct LDL-C method. In our study, a lack of correlation between non-HDL-C and direct LDL-C tests has been observed as TG levels rise and after TG concentrations exceeded 700 mg/dL, direct LDL-C levels were thought to be interfered.lt is concluded that, detailed clinical studies are needed to explore the effectiveness of non-HDL-C test, which has been accepted as an alternative to LDL-C test for patients with high TG levels.

Keywords

Non-HDL-K, LDL-K, ateroskleroz, Non-HDL-C, LDL-C, atherosclerosis

Trigliserit Konsantrasyonlarının Direkt Ldl Kolesterol Düzeylerine Etkisinin Değerlendirilmesi

Abstract

Amaç: Non-HDL kolesterol yüksek trigliserit konsantrasyonuna sahip bireylerde alternatif bir belirteç olarak kabul edilmiştir. Direkt LDL-K ölçümünün yüksek TG konsantrasyonlarında yöntemsel olarak etkilendiği düşünülmektedir. Bu çalışmada, non-HDL-K düzeyleri dayanak alınarak, direkt LDL-K yönteminin hangi TG değerlerinden sonra belirgin olarak etkilendiğini değerlendirmeyi amaçladık.

Materyal ve Metot: Ocak-Haziran 2012 tarihleri arasında Ankara Numune Eğitim ve Araştırma Hastanesi Merkez Biyokimya laboratuarına lipit analizi için gönderilen hasta numuneleri trigliserit düzeyine göre 7 gruba ayrıldı: 1. Grup 0-200 mg/dl (n = 28, yaş 56,2±11,8), 2. Grup 200-400 mg/dl (n= 30, yaş 54,2±10,7), 3.Grup 400-450 mg/dl (n = 52, yaş 55,7±10,9), 4.Grup 450-500 mg/dl (n = 27 , yaş 55,5±10,6); 5.Grup 500-600 mg/dl (n = 25 yaş 56,5±11,3); 6.Grup 600-700 mg/dl (n = 26 , yaş 56,8±11,8); 7.Grup >700 mg/dl (n = 34 , yaş 56,6±11,1)idi. Tüm numunelerde LDL-K analizi, Friedewald yöntemi ile hesaplandı ve direkt LDL-K kiti ile ölçüldü.

Bulgular: Her bir grupta direkt LDL-K ve non-HDL-K arasındaki korelasyon; 1 .Grup (p < 0,001, r: 0,928), 2.Grup (p < 0,001, r: 0,935:); 3.Grup (p < 0,001, r: 0,925); 4. Grup (p < 0,001, r: 0,865); 5.Grup(p < 0,001, r: 0,895); 6.Grup (p < 0,001, r: 0,850) ; 7.Grup (p = 0,117, r:-0,249) idi.
Sonuç: TG düzeylerinin 400 mg/dL nin üzerinde olduğu durumlarda Fridewald formülü ile LDL-K düzeyleri rapor edilememekte, LDL-K düzeyleri direkt LDL-K yöntemi ile çalışılmaktadır. Çalışmamızda TG düzeyleri yükseldikçe direkt LDL-K yönteminin de etkilendiği ve non-HDL-K ile korelasyonunun kaybolduğu gözlenmiştir. Bu durum, TG konsantrasyonu > 700 mg/dl bulunan bireylerde direkt LDL-K yönteminin de TG konsantrasyonundan ileri derecede etkilendiği şeklinde yorumlanmıştır. TG düzeyleri yüksek olan hastaların takibinde direkt LDL-K’ye alternatif olarak sunulan non-HDL-K testi ile ilgili kapsamlı klinik çalışmaların yapılması gerektiği düşünülmektedir.

Kübranur ÜNAL
Sevilay SEZER
Fatma Meriç YILMAZ
Nihal BOĞDAYCIOĞLU

Keywords

Non-HDL-K, LDL-K, ateroskleroz

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