The risk factors of getting Parkinson's?

Some things can increase your chances of getting Parkinson's disease. Doctors call them risk factors.
If you have one of the following risk factors, bear in mind that this doesn't mean you will definitely get the disease. It just means your chances of getting it are somewhat higher than someone who doesn't have the risk factors.
Getting older: The average age for symptoms to start is about 65.[2] You can get Parkinson's while you're still in your 30s, but this is rare.
Being male: Slightly more men than women get Parkinson's.[2] But we don't know why.
Not smoking: If you smoke, you're slightly less likely to get Parkinson's than if you don't. Again, we don't know why this is.[2] But no doctor would recommend you start smoking to reduce your chances of getting Parkinson's.
Having Parkinson's in your family: If your father, mother or one of your brothers or sisters has Parkinson's, you're slightly more likely to get it than someone who doesn't have the disease in his or her family.[1] [3] [4] Some types of Parkinson's, especially those that appear before the age of 40, may be passed down in your family through genes.[5] But this isn't common. Only about 1 in 20 people with Parkinson's have this type of the disease. Parkinson's more often happens in families where no one has had it before.
Doctors have looked at many other things to see whether they might be linked to Parkinson's disease. For example, some research suggests you may be more likely to get Parkinson's if:[2]
You work with pesticides or other chemicals
You've had a head injury.
But more research is needed to know for certain whether these things increase your risk of Parkinson's.
References
Ben-Shlomo Y. How far are we in understanding the cause of Parkinson's disease? Journal of Neurology, Neurosurgery and Psychiatry. 1996; 61: 4-16.
de Rijk MC, Tzourio C, Breteler MM, et al. Prevalence of Parkinsonism and Parkinson's disease in Europe: the EUROPARKINSON Collaborative Study. Journal of Neurology, Neurosurgery and Psychiatry. 1997; 62: 10-15.
Marder K, Tang MX, Mejia H, et al. Risk of Parkinson's disease among first-degree relatives: a community-based study. Neurology. 1996; 47: 155-160.
Jarman P, Wood N. Parkinson's disease genetics comes of age. BMJ. 1999; 318: 1641-1642.
Lazzarini AM, Myers RH, Zimmerman TR Jr, et al. A clinical genetic study of Parkinson's disease: evidence for dominant transmission. Neurology. 1994; 44: 499-506.
Glossary
genes
Your genes are the parts of your cells that contain instructions for how your body works. Genes are found on chromosomes, structures that sit in the nucleus at the middle of each of your cells. You have 23 pairs of chromosomes in your normal cells, each of which has thousands of genes. You get one set of chromosomes, and all of the genes that are on them, from each of your parents.
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