The sense of smell could help doctors diagnose Parkinson’s disease early, if a study currently underway at Halifax is anything to go by. Researchers leading this study are using scratch and sniff tests to understand the role the sense of smell could play in picking up early signals of the disease.
“We are interested in finding ways to pick out people in early stages of Parkinson’s disease, even before the motor symptoms set in.” said Kim Good, co-principal investigator of Predict Parkinson’s and an associate professor in the Dalhousie Department of Psychiatry.
“The study being conducted uses a scratch and sniff test. Forty scratch and sniff strips are given to participants and they are then asked to identify the correct smell of each. Each page of the strips has four potential answers that participants can choose from.
“Smell deficits appear in Parkinson’s patients many years before they start noticing motor problems. If you ask people post-diagnosis … how long back did you start having difficulties with your sense of smell, they would most likely say ‘Oh it’s been years’,” says Good.
The response of the participants to the scratch and sniff tests will allow researchers to pinpoint biomarkers, which in turn, may help them identify who may be at risk of the disease. The test was developed at the University of Pennsylvania and has been in vogue for years in Parkinson’s research. However, never before has it been used for early diagnosis of pre-clinical Parkinson’s. “This study will break new ground,” Good said.
Good is also looking at first-degree relatives of Parkinson’s patients because the likelihood of their developing the disease is about two per cent as compared to one for the general population. The study began in 2007 and is expected to be completed by 2017 and also involves an MRI scan and a cognitive assessment.