People with Parkinson's Disease are three times more likely than non-sufferers to have been troubled by allergic rhinitis --- an inflammatory nasal response to pollen or other airborne particles –-- a new study finds.
The results suggest that allergic diseases, such as hay fever, may be linked to brain inflammation that hastens the onset of the neuro-degenerative disorder, say researchers at the Mayo Clinic in Rochester, Minnesota, US.
They studied 196 people with Parkinson’s disease and 196 others matched for age and gender. A comparison of the two groups revealed that those with Parkinson’s were 2.9 times more likely to have suffered rhinitis earlier in their lives.
[SOURCE: New Scientist, 08 Aug 2006 ]
Rhinitis is when you have frequent sneezing, your nose becomes stuffy (baradong ilong), runny (maraming sipon na lumalabas; watery discharge), and itchy. The eyes and throat may sometimes feel itchy, too. Rhinitis is also a symptom of the common cold, asthma, eczema, and is explained medically as an inflammatory reaction due to exposure to various allergens like house dust, house mites, pet hairs, pollen, pollution, and other airborne particles. I'm pretty sure you have experienced this at some point in your life.
Now, what has sneezing or rhinitis got to do with Parkinson's Disease (PD)?
"People with allergic rhinitis mount an immune response with their allergies, so they may be more likely to mount an immune response in the brain as well, which would produce inflammation. The inflammation produced may release certain chemicals in the brain and inadvertently kill brain cells, as we see in Parkinson's," according to Dr J.H. Bower, lead author of the study.
There is an ongoing hypothesis among neuroscientists that there is an inflammatory component in the development of Parkinson's Disease, and Dr Bower's study might put some degree of validity to that theory. It seems interesting and exciting enough to pursue --- stop the inflammation, stop Parkinson's Disease (wouldn't that be great?) --- but I do have some second thoughts about it. There are many people who suffer from allergic rhinitis, and I don't think all of them will develop PD later on. Besides, Dr Bower's study did not find any association with PD and other inflammatory conditions like asthma, rheumatoid arthritis, lupus, and pernicious anaemia. Again, more and bigger studies are needed. At best, this study provides a potential useful insight into the development of PD.