Assessing Dyslipidemia Through Non-High-Density Lipoprotein (HDL) Cholesterol: A Moroccan Study at Mohammed VI University Hospital

Background: Non-high-density lipoprotein cholesterol (non-HDL-C) includes all atherogenic lipoproteins and is recognized by international guidelines as a secondary therapeutic target, particularly in patients with hypertriglyceridemia.Despite its simplicity and lack of additional analytical cost, its use remains limited in routine clinical laboratory practice.Objective: To assess the distribution of non-HDL-C in a large population of patients undergoing lipid testing, to analyze its concordance with low-density lipoprotein cholesterol (LDL-C), and to evaluate its added value in the presence of hypertriglyceridemia.Materials and methods: A monocentric, retrospective, observational study was conducted in the Central Biochemistry Laboratory of Mohammed VI University Hospital, Oujda, using data extracted from the laboratory information system for lipid profiles performed between January 1 and August 7, 2024.A total of 4,790 lipid profiles from 4,095 distinct patients were analyzed.Non-numeric results or results associated with preanalytical or analytical nonconformities were excluded.Non-HDL-C was calculated as total cholesterol (TC) minus HDL-C.Lipid parameters were described, correlations were assessed using Spearman's coefficient, LDL-C/non-HDL-C concordance was assessed using Cohen's kappa, and factors associated with elevated non-HDL-C were analyzed using binary logistic regression.Results: Mean non-HDL-C concentration was 1.34 ± 0.45 g/L.The prevalence of elevated non-HDL-C was 49.5%, 36.2%, and 24.2% using thresholds of 1.30, 1.45, and 1.60 g/L, respectively.Non-HDL-C was very strongly correlated with TC (ρ = 0.954) and LDL-C (ρ = 0.926).Concordance between LDL-C ≥ 1.30 g/L and non-HDL-C ≥ 1.60 g/L was 91.4% (κ = 0.771).Discordance, defined as normal LDL-C with elevated non-HDL-C, was observed in 3.5% of lipid profiles and was concentrated among patients with TG ≥ 1.50 g/L.Conclusion: Non-HDL-C is strongly correlated with LDL-C but provides complementary information in patients with hypertriglyceridemia. Its calculation requires no additional analytical cost, and systematic reporting of non-HDL-C in lipid profiles may improve the biological identification of atherogenic lipid patterns in clinical laboratory practice.