Meal-induced increases in C-reactive protein, interleukin-6 and tumour necrosis factorα are attenuated by prandial+basal insulin in patients with Type2 diabetes

Aim To determine if a regimen with prandial+basal insulin compared with basal insulin attenuates post-meal inflammatory and glycative biomarkers in patients with Type2 diabetes. Methods This test-meal sub-study in the USA is from a previously reported clinical trial comparing the effect on glycaemic control of 24weeks of thrice-daily pre-meal insulin lispro mix50 (50% insulin lispro, 50% insulin lispro protamine suspension) or bedtime insulin glargine, both plus metformin. In the sub-study, glucose, insulin, triglycerides, high-sensitivity C-reactive protein, tumour necrosis factorα, interleukin-6, methylglyoxal and 3-deoxyglucosone were measured during the post-meal period of a mixed-meal breakfast at the final visit. Prandial+basal (n=25) and basal (n=21) insulin were administered at the same times as during the previous 24weeks. Results Post-meal, the prandial+basal insulin group had significantly higher insulin, lower glucose and triglycerides, as well as lower high-sensitivity C-reactive protein, tumour necrosis factorα and interleukin-6, than the basal insulin group. Glucose incremental area under the concentration curve significantly correlated with high-sensitivity C-reactive protein, tumour necrosis factorα, interleukin-6, methylglyoxal and 3-deoxyglucosone incremental area under the concentration curve. Insulin incremental area under the concentration curve correlated inversely with high-sensitivity C-reactive protein and tumour necrosis factorα incremental area under the concentration curve. However, after adjusting for glucose incremental area under the concentration curve, these inverse correlations were no longer significant. Triglyceride incremental area under the concentration curve was not correlated with any biomarker incremental area under the concentration curve. Conclusions Controlling post-meal hyperglycaemia with prandial+basal insulin in patients with Type2 diabetes attenuates meal-induced increases in high-sensitivity C-reactive protein, interleukin-6 and tumour necrosis factorα compared with basal insulin. The rise in post-meal glucose, but not triglycerides, significantly correlated with the rise in post-meal inflammatory and glycative biomarkers.