Parkinson’s disease is a type of movement disorder that can significantly impair driving skills, cause safety concerns, and force many people with the condition to stop driving a car. That’s because the primary symptoms of Parkinson’s disease can seriously interfere with the complex task of driving a car. These symptoms are:
Tremor -- trembling in the hands, arms, legs, jaw, or head
Rigidity -- stiffness of the limbs and trunk
Bradykinesia -- slowness of movement
Postural instability -- impaired balance
In addition, some people with Parkinson’s disease may develop cognitive impairment: defects in thinking, language, and problem-solving.
Usually, the outward symptoms of Parkinson's are distinctive enough for a doctor to make a diagnosis in the office. There is no blood test or brain scan that confirms the diagnosis. But if you don't respond to the drugs used to treat Parkinson's disease, it’s possible you may have another type of movement disorder that causes the same type of symptoms. Doing additional tests can help your doctor determine if some other problem is causing your parkinsonian symptoms.
Many people with early Parkinson’s disease can safely continue driving, especially if symptoms are controlled. Because Parkinson’s disease worsens over time, however, many people with Parkinson's disease eventually will need to give up driving a car and rely on other forms of transportation.
In American culture, driving is strongly associated with self-reliance and freedom. Some people with the condition may recognize the safety risks and voluntarily agree to limit or stop driving a car. But others may be unable to acknowledge that their driving skills are seriously impaired and insist on driving despite the safety risks to themselves and others.
How Parkinson’s Disease Symptoms Affect Driving Skills
Parkinson’s disease symptoms vary from patient to patient. They can range from mild to severe. But even in mild cases, common symptoms such as shaking in the arms, hands, or legs; impaired balance; and slowed physical and mental responses can affect driving skills.
Episodes of tremor, for example, often begin in a hand or a foot and can affect the ability to operate a car’s controls. Rigidity can result in jerky motions while steering. Slow movement can interfere with braking in heavy traffic or ability to quickly react to road hazards. Postural instability often results in a stooped posture in which the head is bowed and shoulders are drooped, further reducing drivers’ awareness of their surroundings.
For many people with early Parkinson’s disease, medications can reduce symptoms. But medications may have side effects, such as drowsiness, that can affect driving as well. It can be difficult for doctors to devise a medication plan that reduces the primary symptoms of Parkinson’s disease and allows some patients to drive without causing side effects that make driving a car even more dangerous.