An estimated 1.2 million people die from traffic crashes worldwide each year, and one-third of drivers involved in serious crashes suffer from a chronic medical condition. But a new study from Stanford and the University of Toronto shows that a simple medical warning from physicians to patients who may be medically unfit to drive could prevent some of these accidents.
Researchers examined 100,075 adult patients in Ontario, Canada who received medical warnings from physicians between 2006 and 2010, and they found a 45 percent reduction in the risk of serious road crashes in the year following the warnings. The findings, which appear today in the New England Journal of Medicine, also suggest that nearly $200 million a year would be saved in the U.S. because of prevented road crashes. I elaborate more in a story:
In the study, 95 percent of those patients who received warnings had at least one of the 20 most common diagnoses that may indicate problems with driving, and 21 percent had at least five of the diagnoses that justified a warning. Those diagnoses include alcoholism, epilepsy, dementia, stroke and sleep apnea.
The study showed a marked decrease in the number of car crashes as a result of the physicians’ reports. Prior to warnings, the patients had a total of 1,430 crashes over a three-year period, averaging about 466 per year. In the year post-warnings, the rate dropped to about 273 road crashes. [Don Redelmeier, MD, professor of medicine at University of Toronto] described the decrease as “immediate, profound and sustained,” particularly among drivers who had multiple diagnoses.
But Redelmeier and Stanford statistician Rob Tibshirani, PhD, also found that patients who received these warnings were more depressed and less likely to pay a return visit to their doctor. “This doesn’t mean that doctors should stay silent about the situation,” Redelmeir cautioned. Instead, he said, “Physicians need to be sensitive, compassionate and prepared to address adverse consequences in the aftermath of a warning.”
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