[Laryngeal manifestations in patients with Parkinson disease]

Impairments of articulation, respiration, and phonation are a common symptom of Parkinson's disease and may result in reduced communication. Previous observations have shown a high incidence of laryngeal abnormalities. However, no relevant data were available for gender differences of laryngeal abnormalities in Parkinson's disease.

Thirty-nine female and 61 male patients with Parkinson's disease were examined. The laryngeal function was explored by laryngoendoscopy and laryngostroboscopy in respiration and production of [i:] during normal pitch and normal loudness.

Abnormal function of vocal cord abduction and adduction were observed in 54% of the women and 39% of the men; more patients had reduced abduction. Bilateral vocal fold atrophy was seen in 36% of the women and 56% of the men, while 41% of the women and 57% of the men had a bilateral hypertrophy ventricular fold. Phase closure incompetence was found in 60.5% of the women and 49% of the men. Abnormal amplitude and mucosal waveform were seen in more male patients, while 30.7% of the women and 25% of the men had a laryngeal tremor. Gender differences were observed with respect to common laryngeal symptoms.

This study concludes that laryngeal abnormalities in Parkinson's disease show a high degree of gender differences. The percentage of patients with abnormal abduction of the vocal cord was higher than has been reported in other studies. Vocal-fold bowing appear to be related to vocal fold atrophy. Although patients with Parkinson's disease frequently exhibit vocal fold atrophy, other mechanisms and causes should be discussed. Patients with tremor and common laryngeal symptoms were observed. These findings were not expected and further studies of this phenomena would be useful.