Objective Patients with Parkinson's disease (PD) frequently complain of a diminished sense of smell. Less frequently, they may complain of taste impairment. In the present study, we investigated the symptoms, frequency, and severity of taste impairment as well as smell impairment in PD patients and compared the results with those of age- and sex-matched healthy controls.
Patients and Methods We interviewed 285 PD patients (120 men, 165 women) without dementia or nasal problems. Control subjects comprised 61 (20 men, 41 women) healthy spouses of the PD patients. Alteration of smell and taste sense lasting more than 3 months was defined as abnormal.
Results One hundred and sixteen patients with PD complained of smell impairment and 26 complained of taste impairment. Only 5 controls complained of smell impairment, and no control subjects reported taste impairment. Taste impairment was more marked in patients with smell impairment. Impaired taste included diminished taste perception in 21 patients, altered sense of taste in 4 patients and burning mouth in 1 patient.
Conclusion Taste as well as smell perception is impaired in patients with PD. The frequency of smell and taste impairments tended to increase with disease progression.