A friend of mine asked me the other day if there were any risk factors for Parkinson’s….e.g., if you did skydiving as a child, you are more likely to get Parkinson’s.
Yes, there are risk factors (skydiving is not one of them). No, none of them apply to me…with a couple exceptions.
The biggie, which we all have, is age. My neurologist told me that, at 57, I am at the median age for diagnosis. There is early onset Parkinson’s (Michael J. Fox was 29 when he started showing Parkinson’s symptoms.). However, like Alzheimer’s, Parkinson’s is largely a disease of the old. This is the major factor that makes Parkinson’s less “glamorous” (from a fund-raising perspective) than say, breast cancer or leukemia or even Jerry Lewis’s cause of muscular dystrophy. No one is going to put on a telethon to cure Parkinson’s. I’ve thought about joining a support group but they’re all based in senior nursing homes, which would be just a bit too depressing for me.
Other risk factors, none of which apply to me:
—Genetics — Scientists have discovered abnormal genes associated with Parkinson’s and have identified up to 18 gene loci (potential DNA sites) that may be involved. These abnormal genes increase one’s risk but do not directly cause the disease. It is thought that more than one factor (like environmental toxins) needs to also be present to develop the disease. A family history of PD in a first degree relative is seen in about 15% of people with PD.
—Head trauma — It’s not a coincidence that Muhammed Ali has Parkinson’s.
—Exposure to pesticides and herbicides — Rotenone (an insecticide) and Paraquat (an herbicide) have been specifically mentioned. Their chemical structure is similar to MPTP (see below).
—Exposure to a specific recreational drug compound, (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) aka MPTP — This was accidentally discovered in the 1980s when six heroin abusers appeared in a Bay Area hospital “frozen” – conscious but unable to move or speak. After some pretty remarkable medical detective work by J. William Langston and his team, the researchers discovered the drug abusers had all injected a bad batch of heroin which had MPTP as an unintended byproduct. Today, MPTP provides the only way to simulate Parkinson’s in animals for drug testing.
—Chemicals and toxins from processed foods — I have a healthier diet than probably 90% of Americans. Even as a kid, I didn’t go for the Twinkies and potato chips. These days I’m a poster child for a healthy, sustainable diet: lots of fruits and vegetables from the farmers’ market and my garden, small amounts of protein from “happy meat” raised locally without antibiotics.
–And my personal favorite: too much aerobic exercise. (I hasten to add this has no rigorous scientific basis, just one of those things floating around the internet.)
The one risk factor I do have? Rural well water. During my initial diagnostic interview, the neurologist asked me about my source of water when I was growing up. I immediately said it was from a large municipal water supply, drawing from the Missouri River. But I was thinking of St. Louis where I spent the majority of my childhood. My sister pointed out that for the first seven years of my life, we lived outside a small town in western Massachusetts and drew our water from a private well. I still find this dubious. The study that concluded that rural residents who drink water from private wells are much more likely to have Parkinson’s disease was conducted with 700 residents of California’s Central Valley — a place whose water table is crawling with all sorts of nasty pesticides. In contrast, there was no significant agricultural activity where I was born. So I guess I’d better stick with the “too much aerobic exercise” risk factor — it’s as good as any!