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Parkinson disease (PD) is a chronic, progressive neurodegenerative condition, leading to both motor and nonmotor impairments. It is the second most common neurodegenerative disorder after Alzheimer disease. (1, 2) Pathologically, PD is characterized by degeneration of dopaminergic neurons in the substantia nigra pars compacta. (1, 3) The cardinal signs of PD include tremor, rigidity, bradykinesia, and postural instability. (1, 3) The etiology of PD is unknown; however, PD likely results from a complex interaction of factors, including age, genetic susceptibility, and environmental factors. Most cases are sporadic in nature. In a small number of people (<10%), the disease is caused by a genetic mutation. (1, 3)