Study looks at car crashes among diabetics
A new study led by Sunnybrook Health Sciences Centre researcher, Dr. Donald Redelmeier, suggests an adverse association between tighter glycemic control and higher risk of a motor vehicle crash for adult drivers who have diabetes mellitus.
Using a population-based case control analysis over a two year period in Ontario, the doctor and colleagues from the University of Toronto studied diabetic drivers and examined the connection between measured glycosylated hemoglobin – or HbA1c -drivers and the risk of a motor vehicle crash.
Of the 795 total drivers studied, one-in-fourteen had been involved in a crash. The mean HbA1c – the measure of diabetes control over about 8-12 weeks – was lower for those in a crash than those who were crash-free. That is, lower HbA1c levels predicted higher crash risk. In addition, the risk of a crash quadrupled when a driver had a history of severe hypoglycemia that required outside help.
Careful blood glucose control is a fundamental part of diabetes care to reduce complications. Some driving licensing authorities also require adults who hold commercial licenses to document glycemic control. The authors question such licensing policies, saying that “the data suggest that a patient’s HbA1c level is neither necessary nor sufficient for determining fitness-to-drive.”
Dr. Redelmeier, who is also a Professor of Medicine and Physician at Sunnybrooksaid that “the basic implication of the study is to underscore the difficulty in judging fitness-to-drive in adults with diabetes mellitus. This pitfall calls into question traffic laws that prevail in the United States, United Kingdom, Canada, Germany, Holland, Australia, and other countries.”
