Visual-evoked potentials in children and adolescents with newly diagnosed diabetes

Central nervous system impairment is common in patients with diabetes, even in the early stages of the disease. The aim of the study was to evaluate central nerve conduction changes in children and adolescents with newly diagnosed diabetes mellitus using pattern-reversal visual-evoked potentials.

Pattern-reversal visual-evoked potentials were assessed in 48 patients with type 1 (age 11.9±2.9 years) and 18 patients with type 2 (age 14.8±1.3 years) diabetes less than a month after diagnosis and in 33 control subjects (age 12.9±3.9 years).

P100 latencies were significantly delayed in patients with type 1 and 2 diabetes compared with control subjects (p<0.001). There was no correlation between P100 latencies and age at diagnosis. No correlations were found between P100 latencies and HbA1c values in patients with type 1 diabetes. However, P100 latencies were significantly associated with levels of HbA1c in patients with type 2 diabetes (p<0.01). There was a marked inter-individual variability in amplitudes of N75 to P100 in both patients with diabetes and controls. The amplitudes of N75 to P100 were not associated with levels of HbA1c in patients with diabetes. Negative correlations between amplitudes of N75 to P100 and age at diagnosis were noted in patients with type 1 diabetes (p<0.05).

The impaired visual-evoked potential latencies in children and adolescents with newly diagnosed diabetes mellitus suggest an early involvement of the optic pathway. Visual-evoked potential could be helpful for the early detection of central nerve conduction changes at this subclinical stage of the disease.