Olfactory testing with "sniffin' sticks" in idiopathic parkinsonism

Olfactory dysfunction seems to be one of the most frequent symptoms in idio pathic parkinsonian syndrome (IPS). In contrast to the increasing number of studies providing evidence of the usefulness of olfactory tests in the dia gnosis of IFS, clinical assessment of olfactory function is rarely performe d. This may be due to the lack of an easy-to-use, inexpensive, standardized , and reliable test. In this study, we administered the newly developed "sn iffin' sticks" test to a group of 40 nondemented IFS patients and compared the results with 40 healthy controls matched for age, gender, and smoking h abits. In all three subtests including odor identification, odor detection threshold,and odor discrimination, the control group scored significantly b etter than the IFS group, yielding a specificity and sensitivity of 90% eac h. Our results indicate that olfactory disturbances in IFS can be found at early stages of the disease, appear bilaterally, and do not correlate with the dominant side of parkinsonism. Therefore, we emphasize that olfactory t esting may be a useful tool in the diagnosis of IPS.