Parkinson’s disease is a brain disorder that leads to shaking, stiffness, and difficulty with walking, balance, and coordination. Symptoms usually begin gradually and get worse over time. As the disease progresses, people may have difficulty walking and talking. They may also have mental and behavioral changes, sleep problems, depression, memory difficulties, and fatigue.
One clear risk factor for Parkinson’s is age. Although most people with Parkinson’s first develop the disease at about age 60, about 5 to 10 percent of people with Parkinson’s have “early-onset” disease, which begins before the age of 50. Early-onset forms of Parkinson’s are often, but not always, inherited, and some forms have been linked to specific gene mutations.