Bayat Arash, Saki Nader, Mirmomeni Golshan, Yadollahpour Ali
Hearing Research Center, Imam Khomeini Hospital, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
Department of Biostatistics and Epidemiology, School of Health, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
Front Neurol. 2019 Jul 16;10:749. doi: 10.3389/fneur.2019.00749. eCollection 2019.
Methadone maintenance treatment (MMT) as the most effective treatment for opioid addictions could induce both reversible and permanent hearing loss. Therefore, early detection of methadone-induced hearing loss is necessary to prevent irreversible cochlear damage. The present study aims to identify the early onset of hearing loss in patients who underwent MMT and to compare them with the age and gender matched normal hearing peers. This was an analytic cross-sectional study conducted on patients ( = 27 males; age range: 18-53 years old) who received 3 months MMT course (MMT group) and a control group consisting of age and gender matched healthy individuals ( = 27 males). Before MMT, all patients underwent conventional audiometry (250-8,000 Hz) and those with normal hearing threshold participated into the study. One month after MMT termination, the patients were assessed for possible hearing loss using conventional pure tone audiometry (PTA), extended high frequency (EHF) audiometry, and distortion product otoacoustic emissions (DPOAEs). Our results demonstrated that the mean EHF thresholds in the MMT patients were significantly greater than the age- and gender-matched healthy controls across all frequencies ( < 0.001). However, there was no statistically significant difference in conventional PTA thresholds between both groups ( > 0.05). DPOAE amplitudes significantly reduced at higher frequencies (3,000-8,000 Hz) in the MMT group, compared to the healthy control group. In contrast to the conventional PTA audiometry, the EHF and DPOAE assessments identified hearing impairments in 11 (40.74%), and 14 (51.85%) of the MMT patients, respectively. The main mechanisms proposed for methadone induced hearing loss are cochlear ischemia following vasospasm or vasculitis, direct effect of opioids on opioid receptors present in cochlear stria vascularis of inner ear, blood-labyrinth selective transport of opioidproteins and receptors, and genetic polymorphism and mutations. The EHF and DPOAE tests have the potential to detect earlier changes in auditory function than conventional frequency audiometry in the MMT patients.
美沙酮维持治疗（MMT）作为治疗阿片类药物成瘾最有效的方法，可能导致可逆性和永久性听力损失。因此，早期发现美沙酮引起的听力损失对于预防不可逆的耳蜗损伤很有必要。本研究旨在确定接受MMT治疗的患者听力损失的早期发作情况，并将他们与年龄和性别匹配的听力正常的同龄人进行比较。这是一项分析性横断面研究，对象为接受3个月MMT疗程的患者（27名男性；年龄范围：18 - 53岁）（MMT组）以及由年龄和性别匹配的健康个体组成的对照组（27名男性）。在MMT之前，所有患者均接受常规听力测定（250 - 8000Hz），听力阈值正常者纳入研究。MMT终止1个月后，使用常规纯音听力测定（PTA）、扩展高频（EHF）听力测定和畸变产物耳声发射（DPOAE）对患者进行可能的听力损失评估。我们的结果表明，MMT患者的平均EHF阈值在所有频率上均显著高于年龄和性别匹配的健康对照组（P < 0.001）。然而，两组之间常规PTA阈值无统计学显著差异（P > 0.05）。与健康对照组相比，MMT组在较高频率（3000 - 8000Hz）时DPOAE振幅显著降低。与常规PTA听力测定不同，EHF和DPOAE评估分别在11名（40.74%）和14名（51.85%）MMT患者中发现了听力障碍。美沙酮引起听力损失的主要机制包括血管痉挛或血管炎后的耳蜗缺血、阿片类药物对内耳耳蜗血管纹中存在的阿片受体的直接作用、阿片蛋白和受体的血迷路选择性转运以及基因多态性和突变。与常规频率听力测定相比，EHF和DPOAE测试有可能在MMT患者中更早地检测到听觉功能的变化。
