|
|
|
|
|
|
|
|
|
|
WASHINGTON, Mar 20, 2001 (United Press International via COMTEX) -- People suffering from Parkinson's disease often suffer from a lack of smell, making eating less enjoyable, but taking a deeper whiff of air seems to help and it may also assist elderly citizens who complain of a lack of interest in food.
"We've known for a while that people with Parkinson's disease cannot smell as well as others, but it was assumed that it had something to do with the brain," Dr. Gordon H. Bower, of Stanford University, told United Press International. "What Sobel and the others showed in the study was that the odor deficit was related to how many smell molecules were inhaled and how powerfully they were inhaled."
"An Impairment in Sniffing Contributes to the Olfactory Impairment in Parkinson's Disease," by lead author, Dr. Noam Sobel, of the University of California at Berkeley, will be published Tuesday in the Proceedings of the National Academy of Sciences.
Parkinson's disease is a neurodegenerative disorder characterized pathologically by progressive neuronal loss, particularly of aminergic brainstem neurons. It primarily affects motor control, but it also affects cognitive and sensory processing. Of the sensory impairments associated with Parkinson's disease, olfactory impairment has received the most attention.
Patients exhibit impairments in odor detection, identification, and discrimination. They can also be at risk for not recognizing smoke in a fire.
Although the presence of an olfactory impairment in patients has been acknowledged for 25 years its cause remains unknown. "Our findings do not suggest that the sniff impairment is the sole cause of the olfactory impairment in Parkinson's patients," Sobel said. "Increasing sniff volume only helped the worst of the performers and did not bring them to normal performance."
"The remaining non-sniffing component of the olfactory impairment is most likely a smelling impairment related to the disease-induced damage found in the neural substrates of the olfactory system," Sobel added. All subjects performed the University of Pennsylvania smell identification test as well as other tests. The UPSIT test consists of 40 scratch-and-sniff presentations of odorants in a four-alternative forced-choice identification paradigm.
The UPSIT is widely used in clinical and experimental settings and enables comparison to published standardized scores based on large normative data sets.
The California researchers found a patients ability to sniff predicted his or her performance on olfactory tasks, i.e., the more poorly patients sniffed, the worse their performance on olfaction tests. They also found that increasing sniff vigor improved olfactory performance in those patients whose baseline performance had been poorest.
"The follow up to this study is to see if the people with Parkinson's who were told to breathe more deeply can continue to do so and if the improvement in smelling continues," co-author John D. E. Gabrieli, of Stanford University, told UPI. "We'd also like to see if taking a deeper breath helps some of the elderly who also suffer from an odor deficit and therefore also lose an interest in food."
By ALEX CUKAN, UPI Science writer
Copyright 2001 by United Press International.
SUBJECT CODE: 01000000 07000000 08000000 13000000
| Health Topics | Drug Information | Dictionaries | Directories | Other Resources |
|
U.S. National Library of Medicine, 8600 Rockville Pike, Bethesda, MD 20894
Copyright and Privacy Policy, We welcome your comments. Last updated: 20 March 2001 |