Motor vehicle accidents are the leading cause of death in people aged 65-74 and the second leading cause of death in those 75 or older. Driving skills are unchanged in the healthy elderly, but illness can make a difference. In particular, diseases of the heart and blood vessels, central nervous system, and diabetes can cause trouble. Fairly far advanced Parkinson's patients had 79 motor vehicle accidents per million miles travelled. If Parkinson's patients are mentally clear their rate is 28 compared to 94 with a learning deficit.
Elderly drivers tend to drive shorter distances at lower speeds and drive less at night.
They make fewer lane changes and avoid rush hours. Deficits in health creep up undetected. Thirteen percent of people 65 and older have visual field deficiencies and half of these are unaware of it. Common problems elderly drivers are failure to yield the right of way, improper turns, failure to read road signs correctly, problems with mixing traffic, and accidents at intersections. Reaction time is said to be poor in the elderly, but response time between seeing an obstacle and applying the brakes is comparable to that in younger people.