In contrast to European governments, which have progressively restricted driving permits for individuals with insulin-dependent diabetes, the United States has been far more liberal in its restrictions. In an attempt to determine the decline in driving capability by insulin dependent adults experiencing hypoglycemia, the University of Virginia’s General Clinical Research Center conducted a study of twenty five adults, measuring both their driving performance as well as their awareness of their driving performance during and after artificially-induced episodes of hypoglycemia. The study participants were infused with intravenous regular insulin, administered to produce mild and moderate hypoglycemic reactions, while they drove high-tech driving simulators. Immediately before and after each test, the participants were asked: “Would you choose to drive right now? Yes/No.” The participants were kept shielded from their blood glucose levels throughout the tests.
The results of the experiment, which appeared in Diabetes Care May ’93, indicate that driving performance was not disrupted with mild hypoglycemia, or after recovery from moderate hypoglycemia. With moderate hypoglycemia, however, 35% of the participants demonstrated disrupted steering as well as compensatory slowed driving.
During both mild and moderate hypoglycemia, participants reported more often that they would not drive, though only half anticipated their reduced driving capacity: 25% with reduced driving capacity said they were willing to continue driving. After experiencing moderate hypoglycemia behind “the wheel,” however, more participants said they were unwilling to drive again, indicating that the experience of driving with hypoglycemia led to increased awareness of reduced driving capacity.