Road traffic accidents and diabetes: insulin use does not determine risk

Aims Progressive restrictions placed on insulin‐treated patients with diabetes exclude them from driving group 2 and class C1 and D1 vehicles. This reflects an assumption that an increased risk of hypoglycaemia in these patients will cause road traffic accidents. These restrictions have been implemented without any consistent evidence that this is the case. The aim of the study was therefore to investigate whether the rate of road traffic collisions in insulin‐treated patients was higher than that of the non‐diabetic population using a population register‐based study. Methods A historical cohort study combined information from the Devon and Cornwall Constabulary database on road traffic collisions with the district wide retinal screening database, to provide an anonymized matched database of road traffic collisions in the diabetic population. Accident rates were calculated in the diabetic population and compared to rates in the non‐diabetic population using relative risks. Results The estimated overall annual accident rate for the non‐diabetic population was 1469 per 100 000 vs. 856 per 100 000 for the diabetic population as a whole (Chi‐squared, P