ABSTRACT
Objective To evaluate the value of low-density lipoprotein-cholesterol (LDL-C) and non-high-density lipoprotein-cholesterol (non-HDL-C) in differential diagnosis of familial hypertriglyceridemia (FHTG) and familial combined hyperlipidemia (FCHL).Methods We recruited 9 FHTG pedigrees (94 subjects) and 24 FCHL pedigrees (94 subjects) and then divided them into affected groups and non-affected groups according to lipid abnormality.Another 10 normal control pedigrees (57 subjects) served as controls.We compared the routine lipid levels such as triglyceride (TAG),total cholesterol (TC),HDL-C and LDL-C and non-HDL-C between the groups.After stratification based on TAG level,we observed the relationship between LDL-C and non-HDL-C.Last we confirmed and analyzed the cut-off value of differential diagnosis between FHTG and FCHL with receiver operating characteristic (ROC) curve.Results The levels of TAG,TC,and non-HDL-C were significantly higher in the affected group of FHTG than in the non-affected group of FHTG and the normal group (P＜0.01 or P＜0.05).The levels of TAG,TC,HDL-C,LDL-C and non-tHDL-C wcrc significantly higher in the affected group of FCHL than in the non-affected group of FCHL and the normal group (P＜0.01 or P＜0.05).The levels of TAG were significantly higher (P＜0.01) while TC,HDL-C,LDL-C and non-HDL-C levels were significantly lower (P＜ 0.01 or P＜0.05) in the affected group of FHTG than in the affected group of FCHL.The association between LDL-C and non-HDL-C was positive both in FHTG and FCHL,but the relationship became weaker as TAG level increased.The cut-off value of LDL-C and non-HDL-C was 3.575 mmol/L and 4.525 mmol/L,respectively.Conclusion In addition to the routinely used lipid indexes,non-HDL-C may be a new index for differential diagnosis of FHTG and FCHL,and may be superior to LDL-C in this regard.