Early Diagnosis of Hearing Loss in Patients Under Methadone Maintenance Treatment

Abstract

Background and Objective: 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. Methods: This was an analytic cross-sectional study conducted on patients ( n = 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 ( n = 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). Results: 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 ( p < 0.001). However, there was no statistically significant difference in conventional PTA thresholds between both groups ( p > 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. Conclusion: The EHF and DPOAE tests have the potential to detect earlier changes in auditory function than conventional frequency audiometry in the MMT patients.

Hearing and Vestibular Loss with Misuse of Opioids and Illicit Drugs: A Review of the Literature

“…Vestibular function was not addressed. Bayat et al [2019] reported permanent bilateral HL in a group of 11 of 27 men in a treatment program undergoing methadone maintenance. HL onset (sudden vs. progressive), degree, and vestibular function were not reported.…”

“…One additional study [Józefowicz-Korczynska et al, 1994] reported vestibular and audiometric results for people addicted to "drugs" that were not specified beyond noting inclusion of opiates, barbiturates, and inhalants. The remaining 27 studies (61%) reported ototoxicity from prescription of opioids including morphine, oxymorphone, hydrocodone, oxycodone [Kurnatowski and Garganisz, 1996;Ho et al, 2007;Rawool and Dluhy, 2011;Kopec and Nelson, 2012;Boyle and Rosenbaum, 2013;Helander et al, 2014;MacDonald et al, 2015;Leache et al, 2016;Ntranos et al, 2017;Mozeika et al, 2020], the combination of an opioid (hydrocodone, codeine, oxycodone, or dextropropoxyphene) and acetaminophen [Ramsay, 1991;Friedman et al, 2000;Oh et al, 2000;Blakley and Schilling, 2008;Rigby and Parnes, 2008;Freeman et al, 2009;Novac et al, 2015], and maintenance medications that included methadone or propoxyphene [Lupin and Harley, 1976;Harell et al, 1978;van Gaalen et al, 2009;Christenson and Marjala, 2010;Shaw et al, 2011;Vora-subin et al, 2013;Bayat et al, 2019;Ghasemi et al, 2019;Repple et al, 2021].…”

“…Most publications (35/44 or 79.5%) were case reports of 1-9 patients. Of the remaining 9 studies (20%) involving larger cohorts, 2 reported results for use of illicit drugs [Iqbal, 2002b;Moreira et al, 2012], 6 reported on misuse of prescription opioids [Kurnatowski and Garganisz, 1996;Friedman et al, 2000;Freeman et al, 2009;Rawool and Dluhy, 2011;Bayat et al, 2019;Mozeika et al, 2020], and 1 reported on "drugs" that included both opioids and illicit substances [Józefowicz-Korczynska et al, 1994]. Results from Józefowicz-Korczynska et al [1994] are not included in Table 1 because data for all substances were reported in aggregate.…”

“…The underlying cause of opioid-induced HL, however, is not known. Potential mechanisms have been proposed, including ischemic damage, hypoxic changes within the cochlea, genetic variations in metabolic processes, or effects on homeostasis such as a disruption of the endocochlear potential [Kopec and Nelson, 2012;Saifan et al, 2013;Oroei et al, 2018;Bayat et al, 2019]. Given the heterogeneity of onset, degree, and symmetry among cases, individual differences could be mediated by type of substance(s) used, age, gender, route of ingestion (e.g., oral, injected, inhaled), genetic and metabolic factors, and comorbid medical conditions such as cardiac or renal failure [Ganesan et al, 2018].…”

Novel homozygous variants in the TMC1 and CDH23 genes cause autosomal recessive nonsyndromic hearing loss

“…Audiological tests were executed to categorize HL as mild (20-40 dB HL), moderate (41-70 dB HL), severe (71-95 dB HL), or profound (>95 dB HL) (Shinagawa et al, 2020). These assessments were executed in a standard anechoic chamber with a pure-tone audiometer at frequencies ranging from 250 to 4000 Hz (Bayat et al, 2019). Imaging investigations, for example, computed tomography (CT) scans and magnetic resonance imaging (MRI), did not reveal any abnormalities in anatomical structures of middle and inner parts of the ear in each patient.…”