Sloppy Headlines on Parkinson's Disease

Here's a catchy headline that's guaranteed to get your attention: "Smoking and Caffeine May Protect Against Parkinson's Disease."

It was written by the good folks at the Duke University press office. But it does a disservice to anyone who has Parkinson's disease, or cares for or loves someone with the neuro-degenerative condition.

To make matters worse, it gave journalists permission to use similarly dumb headlines for their copy, like this one from the Miami Herald: "Study: Cigarettes, coffee may help ward off Parkinson's."

How sloppy is the Duke press release on Parkinson's disease? Let me count the ways:

1. Regular readers of The Health Media Watch should pick up right away on the "Mighty May" in this title. Whenever you read the word "may" in a health article (or press release) you should always add the phrase "or may not" to the sentence. In other words, "Smoking and Caffeine May or May Not Protect Against Parkinson's Disease."

2. The risk picture is incomplete. "Individuals with Parkinson's disease were half as likely to report ever smoking and a third as likely to report current smoking compared with unaffected relatives," according to the press release. No clue what the absolute risk is of developing Parkinson's disease in one's lifetime as to compared to, oh let's say, LUNG CANCER.

Instead we get just the following dutiful sentence: "Smoking cigarettes and consuming copious amounts of caffeine carry their own risks and should not be taken up in an attempt to avoid developing Parkinson's disease, cautions study investigator Burton L. Scott, M.D., Ph.D., associate professor of medicine."

For the record, about 1 in 100 (or 1%) of people develop Parkinson's disease at some point in their LIFETIME, according to data from the Centers for Disease Control.

But a 68 year-old man who has smoked two packs per day for 50 years and continues to smoke has a 15% chance of developing lung cancer in just the NEXT TEN YEARS (Bach PB, et al. Journal of the National Cancer Institute, 2003).

3. An association does not prove causation. Maybe the folks with Parkinson's were less likely to have smoked because they have less addictive personalities. In that case, smoking would be a side effect of whatever genetic predisposition made you less likely to develop Parkinson's disease. Or maybe, as Maggie Fox of Reuters pointed out in her article, people who are predisposed to developing Parkinson's disease just don't like coffee as much as their counterparts.