New test of odor pleasantness in Parkinson's disease

The New Test of Odor Pleasantness (NTOP) evaluates the hedonicity of olfactory stimulants. The aim of this study was to compare results of the NTOP, the Sniffin' Sticks test, and the Odorized Marker Test (OMT) in patients with Parkinson's disease (PD). The study sample comprised 30 PD patients (mean age 71±7.36 years) and the control group made up of 31 non-PD subjects (mean age 68±12.39 years). Sociodemographic data, medical history and tests of cognitive function were investigated. Olfaction was evaluated using the NTOP, Sniffin' Sticks test and OMT. The PD patients, compared with the control group, recorded significantly lower scores on all three tests: NTOP (p=0.00), Sniffin' Sticks (p=0.02), OMT (p=0.00). The NTOP was the test preferred by 55% of the subjects. This preference was more marked in the PD group. This study shows that the NTOP is a valuable method within the complex array of olfactory screening tools used in PD.