Berendse HW, Roos DS, Raijmakers P, Doty RL.
J Neurol Sci. 2011 Jun 24. [Epub ahead of print]
"We know that smell sense is abnormal in the majority of people with Parkinson's and is at least as common as the tremor. It has previously been suggested that abnormal smell sense (hyposmia) does not worsen with progression of Parkinson's and therefore whilst a useful marker for Parkinson's overall, it might be less useful for monitoring disease. However, this study suggests that in the early stages of Parkinson's, deterioration in smell sense did correlate with disease severity - the movement symptoms, the other symptoms and the imaging. This is a useful finding and suggests that smell sense could possibly be used to monitor Parkinson's in the early stages"