Electroretinographic oscillatory potentials in insulin-dependent diabetes patients: A long-term follow-up

The aim of this research was to study the relevance of long-term follow-up of electroretinographic oscillatory potentials (OPs) in predicting the onset of minimal non-proliferative diabetic retinopathy in insulin-dependent diabetes patients.

A total of 80 insulin-dependent diabetics, with normal fundi and normal OPs at first examination, were followed prospectively for 10 years. Oscillatory potentials were measured and fundus examinations performed once or twice per year.

During follow-up, 35% of patients developed diabetic retinopathy after a mean disease duration of 12 +/- 2 years. A decrease in OP amplitudes was seen in 46% of this group, but reductions were also seen in the 25% of patients whose fundi remained normal. Statistical analysis of best-fit survival curves shows a significant difference (p < 0.001) in the point of Kaplan-Meiers' curve maximal linearity (TmaxS).

It appears that eyes with reduced OP amplitude have a greater probability of developing diabetic retinopathy. Subnormal OP amplitudes are not proof of real concomitant visible vascular damage, but may reflect a predisposition to functional neurosensorial disorder.