Funding agencies: This study was supported by NIH NS060722, Penn State Hershey Medical Center CTSI (NIH UL1 TR000127), GCRC Construction (C06 RR016499), and CTSI (TL1 TR000125) research grants. Dr. Chen is supported by the intramural research program of the NIH, the National Institute of Environmental Health Sciences (Z01-ES-101986).
History of smoking and olfaction in Parkinson's disease
Article first published online: 16 MAY 2014
© 2014 International Parkinson and Movement Disorder Society
Volume 29, Issue 8, pages 1069–1074, July 2014
How to Cite
Lucassen, E. B., Sterling, N. W., Lee, E.-Y., Chen, H., Lewis, M. M., Kong, L. and Huang, X. (2014), History of smoking and olfaction in Parkinson's disease. Mov. Disord., 29: 1069–1074. doi: 10.1002/mds.25912
Relevant conflicts of interest/financial disclosures: Nothing to report.
Full financial disclosures and author roles may be found in the online version of this article.
- Issue published online: 17 JUL 2014
- Article first published online: 16 MAY 2014
- Manuscript Accepted: 8 APR 2014
- Manuscript Revised: 2 APR 2014
- Manuscript Received: 10 JAN 2014
- Parkinson's disease;
Olfactory dysfunction is the most common pre-motor symptom in Parkinson's disease (PD), and smoking is known to be associated with lower risk of PD. This study tested the hypothesis that smoking is associated with better olfaction in PD.
Smoking history was obtained from 76 PD subjects (22 with a history of smoking [smokers], 54 who never smoked [nonsmokers]), and 70 controls (17 smokers, 53 nonsmokers). Olfaction was assessed using the 40-item University of Pennsylvania Smell Identification Test (UPSIT). The olfactory scores between groups and subgroups were compared using analysis of covariance with adjustment for age, gender, and monoamine oxidase B (MAO-B) inhibitor usage.
Overall the olfactory score was lower in PD compared with controls (olfactory scores: 21.5 vs. 33.5, P < 0.0001). Among controls, there was no significant difference in olfaction between smokers and nonsmokers (olfactory scores, 33.2 vs. 34.2; P = 0.95). Among PD subjects, however, smokers scored significantly better regarding olfaction compared with nonsmokers (olfactory scores: 24.4 vs. 19.9, P = 0.02).
These data suggest that a history of smoking is associated with better olfaction among PD patients. The finding may be related to why smoking may be protective against PD. Further studies are needed to confirm this finding and investigate the underlying mechanisms. © 2014 International Parkinson and Movement Disorder Society