Malondialdehyde serum concentration in type 1 diabetic with and without retinopathy

Lipid peroxides are thought to be formed by free radicals and have been implicated in the pathogenesis of diabetes complications. A convenient and sensitive method for estimation of lipid peroxide concentration is the quantitative estimation of their metabolic end-product malondialdehyde (MDA) expressed in mmol/L using the thiobarbituric acid test (TBA-test). We have measured the serum concentrations of MDA in 60 well controlled type I diabetic patients (28 without retinopathy and 32 with retinopathy) and 13 age-matched healthy subjects. Patients with retinopathy showed significantly increased MDA level (2.65+/-1.00) compared to diabetics without retinopathy (1.80+/-0.81) and healthy controls (1.47+/-0.45). The serum levels of MDA correlated best with glycosylated haemoglobin (r=0.28), serum triglyceride concentration (r=0.29) and serum cholesterol concentration. (r=0.47). Increased lipid peroxides suggesting increased free radical activity is associated with retinopathy and this may have pathogenetic implications.