Anti-inflammatory effect of an insulin infusion in patients on maintenance haemodialysis: A randomized controlled pilot study

ABSTRACT Aim: A pilot study to investigate the anti‐inflammatory effect of insulin in patients on maintenance haemodialysis. Background: Elevated concentrations of pro‐inflammatory and oxidative mediators are thought to contribute to the increased cardiovascular risk in haemodialysis. Insulin has been demonstrated to have anti‐inflammatory properties and a continuous low‐dose insulin infusion in critically ill patients is associated with improved outcomes. The anti‐inflammatory effects of insulin in haemodialysis have not been investigated. Methods: In a single‐blind cross‐over study, 11 stable, non‐diabetic, haemodialysis patients received a continuous insulin infusion (Actrapid 2 IU/h) during a dialysis of 4 h or a conventional dialysis in random order. Normoglycaemia was maintained by a modified glucose dialysate and glucose infusion. Blood samples were collected at baseline, 1, 4, 6 and 24 h. C‐reactive protein (CRP), tumour necrosis factor‐α, interleukin‐6, neopterin, vascular cell adhesion molecule 1, protein thiols, dityrosine and peroxides were measured. Results: Insulin produced a significant reduction in median CRP over the immediate dialysis phase (confidence interval) by 6% (2–9% (95% CI), P = 0.006) and an even greater decline at 24 h (19% (8–28%, 95% CI), P = 0.001) compared with values of the conventional dialysis. No significant changes were observed in the other markers. Median glucose levels were comparable during both dialysis sessions. Conclusions: During haemodialysis, insulin may have a modest anti‐inflammatory effect as evident by a reduction in CRP that appears to have a persistent effect over the next 24 h post dialysis. More studies are required to examine longer‐term benefits as well as the potential role in more high‐risk individuals. In this pilot study, an infusion of insulin during haemodialysis resulted in a significant reduction in plasma CRP levels compared with conventional haemodialysis.