Parkinson’s disease is a chronic and progressive brain disorder of the central nervous system. The motor symptoms of Parkinson’s disease result from the death of dopamine-generating cells in the substantia nigra, a region of the midbrain. Dopamine is the chemical that sends messages to the part of the brain that controls movement and coordination. The loss of dopamine causes neurons to fire without normal control, leaving patients less able to control their movement. The disease affects each patient differently and the symptoms can change from day to day.
Parkinson’s disease generally affects individuals over age 50, and men are more likely to have Parkinson’s disease than women. Estimates vary, but research indicates that over one million Americans are living with Parkinson’s disease. The average age at onset is 60, but people have been diagnosed as young as 18.
The exact cause of PD is unknown, but has been attributed to both genetic and environmental factors, such as family history, genetic mutations, drinking well water, and exposure to pesticides or metal.
Mutations in specific genes are associated with PD. These genes include alpha-synuclein (SNCA), parkin (PRKN), leucine-rich repeat kinase 2 (LRRK2 or dardarin), PTEN-induced putative kinase 1 (PINK1), DJ-1 and ATP13A2. The most extensively studied PD-related genes are SNCA and LRRK2.
Although genetics may be a contributing factor, the majority of Parkinson’s cases are not genetically related. You have a slightly higher risk of getting PD if you have a parent or sibling with Parkinson’s; about 15% of individuals with PD have a first-degree relative who has the disease.
There is no cure for Parkinson’s disease, but medications, surgery and multidisciplinary management can provide relief from the symptoms. Diet, exercise and some forms of rehabilitation have some effectiveness at alleviating symptoms. Appropriate treatment can keep most PD patients working and living a full and active life for many years – sometimes even decades.