In everyone with Parkinson’s, both genetic changes and environmental factors likely contribute, to different degrees, to cause the disease. In younger people, especially those who have multiple family members with Parkinson’s, genetics may play a larger role.

People with YOPD are more likely to experience dystonia — prolonged muscle contractions that lead to abnormal postures, such as twisting of the foot. Also, younger people are more likely to develop dyskinesia — involuntary, uncontrolled movements, often writhing or wriggling — as a complication of long-term levodopa use combined with a long course of Parkinson’s disease.

On the other hand, people with YOPD are less likely to have significant problems with balance, or considerable memory or thinking problems (dementia). Progression of disease over time is, in general, slower.

Options for managing Parkinson’s symptoms are essentially the same no matter when Parkinson’s is diagnosed. To delay dyskinesia, younger people may choose to postpone starting medication or begin with Parkinson’s drugs other than levodopa, especially if symptoms are mild and don’t interfere with work, physical or social activities. Options may be to start with an MAO-B inhibitor, a dopamine agonist; or, when tremor is particularly prominent, an anticholinergic drug.

Physicians and researchers have long engaged in a healthy discussion over the best time to start levodopa. Some believe it’s better to start sooner to control symptoms, maximise the quality of life and allow a person to remain active as long as possible. Others hold off to potentially delay motor complications, such as dyskinesia. Ask your physician for his or her take on this issue and consider the pros and cons of both approaches. Work closely with your movement disorder specialist to determine which medication is right for you and when.