Grant: Project Grant

Motor vehicle crashes result in 1.5 million deaths and 78 million injuries worldwide each year. Some crashes can be prevented by restricting driving for individuals with medical conditions that might cause sudden incapacitation while diving (eg. epilepsy, sleep apnea). These driving restrictions are a major interruption to patients' lives and can only be justified if they prevent crashes. About 4,000 Canadians will have an implantable cardiac defibrillator (ICD) implanted this year. ICDs treat life-threatening cardiac rhythm abnormalities and prevent cardiac arrest. The leads that attach an ICD to the heart can cause cardiac rhythm problems soon after insertion. In theory, a lead-related heart rhythm problem or device malfunction in the weeks after implantation might occur while the patient is driving, resulting in a crash. Doctors thus warn patients not to drive for one or more weeks after ICD implantation. How many crashes are prevented by restricting driving after ICD implantation? Is the duration of driving restriction too short, too long, or about right? Would driving restrictions be more effective if they were modified? The answers to these questions aren't known since current driving restrictions are based on small, poorly-designed studies that focus on outdated cardiac device technologies. British Columbia's health and driving databases provide a unique opportunity to examine crash risk after ICD implantation. The MVC-ICD study will use health and driving records to compare crash risk among 7,500 ICD patients to crash risk among control patients. The data will be used to develop a score to identify patients at the highest risk of crash. Results will provide an immediate opportunity to improve clinical practice, licensing policy and road safety in Canada and abroad.