A comparison of lipid and lipoprotein measurements in the fasting and nonfasting states in patients with type 2 diabetes

Background: Patients with diabetes often do not reach recommended lipid targets, This may be in part due to the difficulty of obtaining fasting measurements. Objective: To compare fasting and nonfasting low density lipoprotein cholesterol (LDLc), non-high density lipoprotein cholesterol (non-HDLc), and low density lipoprotein particle number (LDLP) patients with type 2 diabetes (T2DM) and to determine the effect on assessing treatment success. Research design and methods: Standard lipids and NMR lipoproteins were analyzed at baseline and following a standardized meal in patients with T2DM. Outcomes measures: Primary outcomes were agreement between fasting and nonfasting LDLc, non-HDLc, and LDLP and the agreement between these measures for determining fasting LDLc treatment success. Direct LDL cholesterol (DLDL) was a secondary outcome. Results: Of 31 patients, only 56% of LDLc measurements were equivalent in the fasting and nonfasting states, compared to 97% of DLDLc (p < 0.0001), 94% of non-HDLc (p < 0.001) and 77% of LDLP (p < 0.01) measurements. Assessment of nonfasting lipid values would have resulted in misclassification by treatment target in 15% of LDLc, 3.2% of DLDLc assessments (p < 0.05 vs. LDLc), and 0% of non-HDLc and LDLP assessments (p < 0.01 vs. LDLc). Nonfasting LDLc, non-HDLc, LDLP, and DLDLc correctly identified fasting LDLc classification in 23/27 (85%), 26/30 (87%, p = NS vs. nonfasting LDLc), 16/30 (53%, p< 0.001 vs. nonfasting LDLc), and 24/30 (80%, p = NS vs. nonfasting LDLc), respectively. Conclusions: If confirmed in larger studies, nonfasting non-HDLc may be a suitable proxy for fasting LDLc in patients with T2DM.