premise: Parkinson's disease has afflicted people.
hypothesis: Parkinson's disease . Depression and anxiety are also common occurring in more than a third of people with PD . There is also an increased risk in people exposed to certain pesticides and among those who have had prior head injuries while there is a reduced risk in tobacco smokers and those who drink coffee or tea . In 2015 , PD affected 6.2 million people and resulted in about 117,400 deaths globally . Parkinson 's disease typically occurs in people over the age of 60 , of which about one percent are affected . People with parkinsonism who have increased the public 's awareness of the condition include actor Michael J. Fox , Olympic cyclist Davis Phinney , and late professional boxer Muhammad Ali .