Post-diagnosisReceiving a diagnosis of Parkinson's disease is no picnic for anyone, but many of us young-onset folks wait longer for a diagnosis—and, therefore, treatment—because so many physicians also retain the belief that PD is solely a geriatric disease. The statistics vary, but the Michael J. Fox Foundation reports that "at least one million people in the United States are estimated to have Parkinson's; many of them, perhaps half, are thought to be undiagnosed