The Practical Aspects

Driving With Diabetes Can Be Risky!

Patients with type 1 diabetes are at a higher risk for traffic accidents than people without diabetes, although interestingly, type 2 patients (even those on insulin injections) were at no higher statistical risk.

The good news for people with type 1 diabetes is that both insulin pump therapy and regular glucose monitoring before getting behind the wheel were associated with a lower incidence of driving mishaps.

Type 1 diabetic drivers are at increased risk for driving mishaps, but type 2 diabetic drivers, even on insulin, appear not to be at a higher risk than non-diabetic individuals. Clinical and treatment factors appear to increase risk, e.g., more frequent hypoglycemia while driving, method of insulin delivery, and infrequent self-testing before driving. Physicians are encouraged to talk to their type 1 diabetic patients about hypoglycemia and driving.

The intensive treatment of diabetes to achieve strict glycemic control is a common clinical goal, but it is associated with an increased incidence of hypoglycemia. Becoming hypoglycemic while driving is a hazardous condition and may lead to a greater incidence of driving mishaps.

Diabetics are associated with increased risk of driving mishaps

Type 1 diabetic drivers reported significantly more crashes, moving violations, episodes of hypoglycemic stupor, required assistance, and mild hypoglycemia while driving as compared with type 2 diabetic drivers or spouse control subjects.

Type 2 diabetic drivers had driving mishap rates similar to non-diabetic spouses, and the use of insulin or oral agents for treatment had no effect on the occurrence of driving mishaps. Crashes among type 1 diabetic drivers were associated with more frequent episodes of hypoglycemic stupor while driving, less frequent blood glucose monitoring before driving, and the use of insulin injection therapy as compared with pump therapy. One-half of the type 1 diabetic drivers and three-quarters of the type 2 diabetic drivers had never discussed hypoglycemia and driving with their physicians.

If diabetes is managed by diet and tablets then the patient will be able to retain their license until the age of 70 years unless he/she develops relevant disabilities e.g. visual field or visual acuity problems, requirement for insulin.

The perception of safe driving ability during hypoglycemia in patients with type 1 diabetes

Hypoglycemia places an individual with diabetes at risk for an accident while driving. Again, men were more likely than women to judge that they could drive safely, especially during mild hypoglycemia.

These facts stresses the importance of including education about safe driving practices for patients with insulin-requiring diabetes. Many of us have had patients who have ignored symptoms of hypoglycemia while driving because they were close to their final destination and misjudged their ability to drive safely. The resulting neurocognitive impairment resulted in unsafe driving or, at worst, an automobile accident injuring or killing themselves or others.

Hypoglycemia, when unrecognized during driving, is extremely dangerous and must be dealt with appropriately. Patients with hypoglycemia unawareness and patients who are unable to accurately predict their blood glucose levels are at particular risk. It is therefore important to teach patients to try to accurately predict their blood glucose levels based on symptomatology. This is best done by having patients record their symptoms, predict what their blood glucose levels will be, and then determine the accuracy using blood glucose testing.

Repeated exercises such as this result in an improved ability to predict blood glucose levels

Although, in general, patients are more likely to be able to predict low blood glucose values compared with high blood glucose values, it is essential for patients to practice and reinforce their ability to correlate symptoms and glucose levels. Just as patients are educated not to drive while under the influence of alcohol, they should also be taught to check their blood glucose levels before driving and to eat something if their blood glucose levels are less than 80 mg/dl.

If glucose levels are less than 70 mg/dl, we recommend they drink juice, wait 10–15 min, recheck their blood glucose levels and, if their levels are above 80 mg/dl, keep a snack to eat before beginning to drive. They should be certain to carry a fast-acting glucose source, such as glucose tablets, as well as a longer acting snack, such as a cereal bar or peanut butter cracker, with them.

The food should not be placed in a hard to reach area, such as a glove compartment, but should instead be placed on the passenger seat where it is readily accessible should the patient need it during driving. They should be reminded that if they feel symptomatic they should pull over and not resume driving until their blood glucose values have reached safe levels.

Conclusion

There is a need to include `driving’ when discussing other risk-taking behaviors with patients who have insulin-requiring diabetes. Diabetes education and counseling should routinely include recommendations about checking blood glucose levels before driving, treating mild hypoglycemia promptly, and always carrying a fast-acting source of glucose. And, as with other aspects of our education program, the message needs constant reinforcement.