Research from the VA Pacific Islands Health Care System in Honolulu, Hawaii has come up with a new warning sign for Parkinson’s disease — a warning sign that may appear several years before clinical symptoms show up.
The researchers looked at data from an aging study with more than 2200 participants. Their focus? The ability to identify odors.
About the study participants:
- 2267 men of Japanese ancestry
- Average age at time of initial study: 80
- All free of symptoms of dementia at beginning of study
- All free of symptoms of Parkinson’s disease at beginning of study
Researchers checked in with the participants for up to eight years. By the end of the study, thirty-five participants had been diagnosed with Parkinson’s disease. That works out (in a larger sample) to approximately twenty-five out of every ten thousand people. The average age at diagnosis was 83.
So where does sense of smell come in? The VA Pacific Islands Health Care System researchers looked at smell identification test scores and refigured the results. In men who had the highest odor identification scores, the rate of developing Parkinson’s disease was less than nine out of ten thousand people. In men who had the lowest odor identification scores, the rate of developing Parkinson’s disease was more than fifty-four out of ten thousand people.
In other words, losing your ability to smell makes you more than five times more likely to develop Parkinson’s disease.
An impaired sense of smell may help improve early detection of Parkinson’s disease — long before common Parkinson’s-related motor dysfunctions are obvious. Early detection will become even more important when medical interventions are available to slow or stop progression of the disease. We don’t have much in the way of interventions now, but celebrities like Michael J. Fox are working hard to get more money devoted to Parkinson’s research.