[Parkinson's Disease in the Oldest-Old].

The prevalence of Parkinson's disease (PD) has increased globally, especially in older age groups. Older age at onset is associated with more severe motor and nonmotor symptoms at diagnosis and more rapid and severe progression. Because majority of older people have multiple comorbidities, patients with PD may be misdiagnosed. Limited response to L-dopa medication in the older patients has been indicated. The risk of motor complications decreases with increasing age, while the risk of axial complications, hallucinations, and dementia increases. Evidence for many of the currently used PD medications is based on clinical trials with the criteria that exclude older patients, and it will be necessary to establish evidence of medication for PD in older patients.