Speech discrimination is impaired in parkinsonian patients: Expanding the audiologic findings of Parkinson's disease

Background and objectives: Hearing impairment (HI) has been previously demonstrated in patients with Parkinson's disease (PD). Pure Tone Audiometry (PTA) gives no information about patients' ability to hear and understand speech. To find out hearing ability and speech discrimination of PD patients, we expanded audiological evaluation by means of speech audiometry (SA). Patients and methods: We screened a series of consecutive PD patients. Severity of motor symptoms and staging were measured by the UPDRS-III and the H&Y scales. Audiometric evaluation consisted of a standardized audiological examination, PTA and SA. Healthy age- and sex-matched subjects were selected as controls. Results: 45 PD patients and 45 healthy controls were enrolled. PTA confirmed our previous finding of high-frequency HI in PD patients. The mean values for the Speech Recognition Threshold were higher in PD patients as compared with controls. PD patients were more likely to have impaired speech discrimination profiles and higher disease stages. Neither the patients nor the controls showed a significant speech-tone dissociation and rollover phenomenon. Conclusion: Our results confirmed sensorineural HI in PD patients. Moreover, SA showed impaired speech discrimination abilities in PD patients as compared with control group thus expanding the audiologic findings of PD.