Below is an instruction from Human. Write a response.
    ### Instruction:
    How many people are affected by Parkinson disease ?
    ### Response:
    Parkinson disease affects more than 1 million people in North America and more than 4 million people worldwide. In the United States, Parkinson disease occurs in approximately 13 per 100,000 people, and about 60,000 new cases are identified each year.  The late-onset form is the most common type of Parkinson disease, and the risk of developing this condition increases with age.
    