Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the present study we sought to determine whether the olfactory deficits of parkinsonism are related to the cognitive and perceptual-motor manifestations of the disease. Pearson correlation coefficients were computed among a number of olfactory, neurological, and neuropsychological measures obtained from 58 Parkinson's disease patients, including the University of Pennsylvania Smell Identification Test, a modified Randt memory test, a reaction time test, a finger-tapping test, ratings of motor and neurological function, and selected verbal and performance subtests of the Wechsler Adult Intelligence Scale--Revised. Data from 38 patients with Parkinson's disease who received odor detection threshold testing were also evaluated. The intercorrelation matrix was subjected to a principal components factor analysis which yielded six clear-cut factors: cognitive/memory, gross motor, oral motor, fine motor, olfactory, and tremor. The olfactory factor received strong and nearly exclusive loadings from the olfactory measures (which did not evidence meaningful loadings on any of the other factors). A ten-trial jackknife procedure revealed the factor structure to be stable. Further support of the independence of the olfactory variables from the other measures was provided by multiple regression and canonical correlation analyses. Overall, these findings lend support to the hypothesis that the olfactory disorder of parkinsonism is independent of the cognitive, perceptual-motor, and memory manifestations of the disease.
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PMID:The olfactory and cognitive deficits of Parkinson's disease: evidence for independence. 291 66

Olfactory and gustatory disorders increase with advancing age. Moreover, olfactory disorders are common in neurodegenerative disorders, especially in idiopathic Parkinson's disease (IPD) and Alzheimer's Disease (AD). Since the decrease in olfactory function is usually gradual, it often remains undetected. Given the poor self-assessment of olfactory function, olfactory testing is mandatory in suspected cases to establish the diagnosis of hyposmia or anosmia. The high rate of anosmia over the age of 70 is suspected to be due to several factors such as changes in the olfactory epithelium (reduced mucus secretion, hormonal changes, changes in epithelial thickness, for example), and the reduced neuroregeneration rate in olfactory receptor cells themselves. There is no known adequate treatment for stopping or reversing this age-related decline in olfaction. In IPD, olfactory impairment precedes motor symptoms by years and is independent of dopaminergic loss. Using fMRI, altered neuronal activity in the amygdaloid complex and hippocampal formation during olfactory stimulation have been demonstrated, as has a link between the expression of olfactory event-related potentials and olfactory-induced brain activity. In AD--by contrast with IPD--the severity of the disease and the olfactory disorder correlate. The olfactory disorders alone, however, cannot distinguish between AD and IPD. A complete loss of gustatory function is rare, while dysgeusia is common, especially with increasing age. There are multiple possible explanations, including concomitant disease and the side-effects of medication. These need to be established on the basis of exact history and examination. Treatment remains difficult.
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PMID:Ageing, neurodegeneration, and olfactory and gustatory loss. 2008 14