The relationship between the acute changes in the systemic inflammatory response, lipid soluble antioxidant vitamins and lipid peroxidation following elective knee arthroplasty

The aim of the present study was to examine the time course of the change in the concentrations of plasma retinol, α-tocopherol, lutein, lycopene, α-carotene, β-carotene (antioxidant vitamins) and malondialdehyde (lipid peroxidation) in patients following elective knee arthroplasty. Patients ( n = 20 ) who underwent an elective knee arthroplasty, had venous blood samples withdrawn pre-operatively and at 12, 24, 48, 72 and 168 h after the start of surgery for the analysis of circulating concentrations of C-reactive protein, albumin, cholesterol, triglycerides and malondialdehyde and also the lipid soluble antioxidants vitamins. Over the study period of 0–168 h there was a significant increase in circulating C-reactive protein concentrations (peak 48 h, P < 0.001 ) and a significant fall in albumin, cholesterol and triglyceride concentrations (trough 48 h, P < 0.001 ). Malondialdehyde concentrations fell by approximately 35% ( P < 0.001 ) during the study period. However, they did not alter significantly over the study period when adjusted for triglyceride ( P = 0.309 ). The plasma concentrations of retinol, α-tocopherol, lutein, lycopene, α-carotene and β-carotene all fell ( P ⩽ 0.001 ). When adjusted for cholesterol, the reductions in plasma concentrations of α-tocopherol, lutein, lycopene, and β-carotene in the post-operative period were no longer statistically significant. The results of the present study indicate that, in apparently healthy subjects undergoing an acute inflammatory insult, circulating lipid soluble vitamin antioxidants are transiently reduced. However, when corrected for lipids the concentrations were similar to those of baseline. In the absence of an increase in lipid peroxidation such falls in plasma concentrations of lipid soluble vitamins are unlikely to be a reliable measure of status.