De Groote Evelien, Bockstael Annelies, Botteldooren Dick, Santens Patrick, De Letter Miet
Department of Rehabilitation Sciences, Ghent University, Belgium.
Acoustics Research Group, Department of Information Technology, Ghent University, Belgium.
J Speech Lang Hear Res. 2021 Apr 14;64(4):1354-1368. doi: 10.1044/2020_JSLHR-20-00594. Epub 2021 Mar 26.
Purpose Several studies have demonstrated increased auditory thresholds in patients with Parkinson's disease (PD) based on subjective tonal audiometry. However, the pathophysiological mechanisms underlying auditory dysfunction in PD remain elusive. The primary aim of this study was to investigate cochlear and olivocochlear function in PD using objective measurements and to assess the effect of dopaminergic medication on auditory function. Method Eighteen patients with PD and 18 gender- and age-matched healthy controls (HCs) were included. Patients with PD participated in medication on and off conditions. Linear mixed models were used to determine the effect of PD on tonal audiometry, transient evoked and distortion product otoacoustic emissions (OAEs), and efferent suppression (ES). Results Tonal audiometry revealed normal auditory thresholds in patients with PD for their age across all frequencies. OAE signal amplitudes demonstrated a significant interaction effect between group (PD vs. HC) and frequency, indicating decreased OAEs at low frequencies and increased OAEs at high frequencies in patients with PD. No significant differences were found between patients with PD and HCs regarding ES. In addition, no significant effect of medication status was found on auditory measurements in patients with PD. Conclusions Altered OAEs support the hypothesis of cochlear alterations in PD. No evidence was found for the involvement of the medial olivocochlear system. Altogether, OAEs may provide an objective early indicator of auditory alterations in PD and should complement subjective tonal audiometry when assessing and monitoring auditory function in PD.
目的 多项研究已基于主观纯音听力测定法证明帕金森病（PD）患者的听觉阈值升高。然而，PD患者听觉功能障碍的病理生理机制仍不清楚。本研究的主要目的是使用客观测量方法研究PD患者的耳蜗和橄榄耳蜗功能，并评估多巴胺能药物对听觉功能的影响。方法 纳入18例PD患者和18例性别及年龄匹配的健康对照者（HCs）。PD患者参与药物开启和关闭状态的测试。使用线性混合模型确定PD对纯音听力测定、瞬态诱发耳声发射和畸变产物耳声发射（OAEs）以及传出抑制（ES）的影响。结果 纯音听力测定显示，PD患者在所有频率下的听觉阈值与其年龄相符，均正常。耳声发射信号幅度在组（PD与HC）和频率之间显示出显著的交互作用，表明PD患者低频耳声发射降低，高频耳声发射升高。PD患者与HCs在传出抑制方面未发现显著差异。此外，未发现药物状态对PD患者的听觉测量有显著影响。结论 耳声发射改变支持PD患者耳蜗改变的假说。未发现内侧橄榄耳蜗系统受累的证据。总之，耳声发射可能为PD患者听觉改变提供客观的早期指标，在评估和监测PD患者的听觉功能时应补充主观纯音听力测定。
