Sympathetic sudomotor disturbance in early type 1 diabetes mellitus is linked to lipid peroxidation.

The present study was performed to determine whether increased lipid peroxidation, as assessed from malondialdehyde (MDA) excretion, is associated with deterioration in peripheral nerve function in early type 1 diabetes mellitus. These parameters were measured annually for 3 years in 36 patients who entered the study less than 2 years after the diagnosis of diabetes. Malondialdehyde excretion was 1.51 +/- 0.20 micromol/g creatinine in the controls, and 2.43 +/- 0.21, 2.39 +/- 0.22, and 1.93 +/- 0.21 micromol/g creatinine at the first, second, and third evaluations, respectively (P < .005). The increased MDA was seen only in the female participants. Malondialdehyde excretion was increased in those with high vs low hemoglobin Alc across all years (P < .05). Malondialdehyde excretion correlated negatively with sudomotor function below the waist. The mean sweat production from the 3 evaluations correlated with mean MDA excretion across all years in the proximal leg (r = -0.42, P < .005) and distal leg (r = -0.40, P < .01). Below the waist, sweating correlated with MDA (r = -0.40, P < .01) as did total sweat (r = -0.38, P < .01). The response amplitudes of the peroneal nerves correlated negatively with MDA excretion (for the mean values at the second 2 evaluations, P < .005, r = -0.45). Tests of sensory function correlated inconsistently with MDA excretion. In summary, lipid peroxidation, as assessed from malondialdehyde excretion, is associated with sudomotor dysfunction in early diabetes.