EXAMINATION OF HEARING IN ALCOHOLICS

The Effects of Substance Misuse on Auditory and Vestibular Function: A Systematic Review

BACKGROUND

Chronic substance misuse is an ongoing and significant public health concern. Among a myriad of health complications that can occur, substance misuse potentially causes ototoxic effects. Case reports, retrospective chart data, and a few cohort studies suggest that certain prescription opioids and illicit drugs can have either temporary or permanent effects on auditory and/or vestibular function. Given the steady rise of people with a substance-use disorder (SUD), it is of growing importance that audiologists and otolaryngologists have an insight into the potential ototoxic effects of substance misuse.

OBJECTIVES

A systematic review was conducted to (1) synthesize the literature on the illicit drugs, prescription opioids, and alcohol misuse on the auditory and vestibular systems, (2) highlight common hearing and vestibular impairments for each substance class, and (3) discuss the limitations of the literature, the potential mechanisms, and clinical implications for clinicians who may encounter patients with hearing or vestibular loss related to substance misuse, and describe opportunities for further study.

DESIGN

Systematic searches were performed via PubMed, Scopus, and Google Scholar, and the final updated search was conducted through March 30, 2022. Inclusion criteria included peer-reviewed articles, regardless of study design, from inception until the present that included adults with chronic substance misuse and hearing and/or vestibular complaints. Articles that focused on the acute effects of substances in healthy people, ototoxicity from already known ototoxic medications, the relationship between hearing loss and development of a SUD, articles not available in English, animal work, and duplicates were excluded. Information on the population (adults), outcomes (hearing and/or vestibular data results), and study design (e.g., case report, cohort) were extracted. A meta-analysis could not be performed because more than 60% of the studies were single-case reports or small cohort.

RESULTS

The full text of 67 studies that met the eligibility criteria were selected for the review. Overall, 21 studies reported associations between HL/VL related to illicit drug misuse, 28 studies reported HL/VL from prescription opioids, and 20 studies reported HL/VL related to chronic alcohol misuse (2 studies spanned more than one category). Synthesis of the findings suggested that the misuse and/or overdose of amphetamines and cocaine was associated with sudden, bilateral, and temporary HL, whereas HL from the combination of a stimulant and an opioid often presented with greater HL in the mid-frequency range. Reports of temporary vertigo or imbalance were mainly associated with illicit drugs. HL associated with misuse of prescription opioids was typically sudden or rapidly progressive, bilateral, moderately severe to profound, and in almost all cases permanent. The misuse of prescription opioids occasionally resulted in peripheral VL, especially when the opioid misuse was long term. Chronic alcohol misuse tended to associate with high-frequency sudden or progressive sensorineural hearing loss, or retrocochlear dysfunction, and a high occurrence of central vestibular dysfunction and imbalance.

CONCLUSIONS

Overall, chronic substance misuse associates with potential ototoxic effects, resulting in temporary or permanent hearing and/or vestibular dysfunction. However, there are notable limitations to the evidence from the extant literature including a lack of objective test measures used to describe hearing or vestibular effects associated with substance misuse, small study sample sizes, reliance on case studies, lack of controlling for confounders related to health, age, sex, and other substance-use factors. Future large-scale studies with prospective study designs are needed to further ascertain the role and risk factors of substance misuse on auditory and vestibular function and to further clinical management practices.

Auditory assessment of alcoholics in abstinence

Alcoholism is considered the most relevant addiction in the international arena and few investigations have examined the association between sensorineural hearing loss and alcohol abuse, with conflicting results.

AIM

To analyze the effects of alcohol abuse on the auditory system of alcoholics in abstinence taking into account the duration of alcohol abuse and associated noise exposure.

METHOD

our series comprehended 75 individuals, divided into two groups: trial and control. The audiological assessment was made by means of: pure-tone audiometry, transient evoked otoacoustic emissions, tympanometry. The Wilcoxon and Mann-Whitney tests were used in the statistical analysis of the data.

RESULTS

the groups of patients who had been alcoholics evidenced a statistically significant worse performance in the audiological assessment. The combined exposure to alcohol and noise was not synergic on the auditory system.

CONCLUSION

long-term alcohol abuse can damage the cochlear function, specifically the outer hair cells.

Audiovestibular dysfunction in alcohol dependence. Are we worried?

PURPOSE

To study the audiovestibular function in patients of long-term alcohol dependence and compare these changes with social users of alcohol and complete abstainers.

MATERIAL AND METHODS

This was a prospective study of 20 randomly selected patients of long-term alcohol dependence fulfilling International Statistical Classification of Diseases, 10th Revision criteria of alcohol dependence. Audiovestibular function in this group was compared with social user of alcohol and complete abstainers.

RESULTS

Statistically significant elevations of thresholds were found at higher frequencies (4000 and 8000 Hz ) in the alcohol-dependent group (P < .001). Alcohol-dependent patients had elevated thresholds at 4 and 8 kHz. Brainstem-evoked response audiometry showed prolongation of latencies of waves I, III, and V alone with interpeak latencies of I-III and III-V. One third of alcohol-dependent patients had abnormal electronystagmographic (ENG) findings. Abnormal ENG findings were only seen in alcohol-dependent patients with vertigo. There was no significant correlation between duration of alcohol dependence and abnormal ENG.

CONCLUSIONS

Elevated thresholds at higher frequencies can be the only abnormality in alcohol-dependent patients. Presence of vertigo in alcohol-dependent patient may be associated with abnormal ENG findings. There is no correlation of duration of dependence and ENG abnormalities.

Alcohol, auditory functioning and deafness

This paper reviews studies of alcohol and auditory impairment and the treatment of deaf people with alcohol problems and concludes that: (a) alcohol affects auditory functioning, (b) prenatal exposure to alcohol is a risk factor for hearing impairment in FAS children,

Correlations between presbyacusis and extrinsic noxious factors

As part of the longitudinal gerontological and geriatric population study of 70-year-olds in Göteborg, Sweden, the possible correlation between presbyacusis and extrinsic factors affecting health in elderly persons was investigated. Participants from one cohort (F 01) were studied longitudinally at ages 70, 75, 79 and 85 years, and from another cohort (F 06) at age 70 years. A weak correlation between hearing loss and smoking, alcohol abuse and head trauma was found for men and between hearing loss and intake of pharmaceutical agents (especially salicylates) for women.

Acute ethanol effects on sensory/motor function in baboons with a history of chronic ethanol ingestion

Baboons with a history of chronic, daily ethanol ingestion were subsequently studied under conditions that assessed the effects of acute oral self-administration of ethanol on auditory and visual threshold functions and reaction times. During the post-chronic experiment reported herein, the animals consumed specific amounts of ethanol twice weekly (0.1, 0.32, 1.0 or 1.3 g/kg), following which they immediately performed psychophysical tests designed to assess ethanol's effects on sensory thresholds and reaction times. Clear, dose-related increases in reaction times were observed following ethanol doses greater than 0.32 g/kg. Trends within individual threshold functions were consistent with systematic changes in auditory and visual threshold sensitivities of 1-3 dB at the high ethanol doses. Reaction time increases ranged from 25 to 180 ms above baseline levels at the highest dose (a 15% average increase). These general findings however, were in contrast to data obtained in the same animals under conditions of daily, chronic ethanol administration which characteristically showed greater sensory/motor effects of up to twice the magnitude of those observed with single doses.

Ethanol's effects on auditory thresholds and reaction times during the acquisition of chronic ethanol self-administration in baboons

Baboons were trained to ingest ethanol at successively higher ethanol concentrations using oral self-administration techniques. Concurrently, animal psychophysical procedures were employed to determine auditory thresholds and reaction times daily. Maximal consumption of ethanol occurred at concentrations of 6-8% (w/v). During the initial period of ethanol self-administration, both auditory reaction times and auditory thresholds became elevated as animals consumed larger amounts of ethanol. For both the threshold and reaction time measures, the degree of elevation was correlated with the amount of ethanol consumed. These correlations decreased, however, with continued ethanol consumption. The elevations in sensory and motor function recovered to near-baseline levels when ethanol was no longer available.

Audiological investigation of chronic alcoholics

Pure tone audiometry performed on 67 alcoholics showed a sensorineural hearing loss in 70% of the ears examined. The prevalence of the hearing loss was related to the duration of heavy drinking. Twenty-two subjects with hearing loss were evaluated using impedance audiometry, SISI test, tone decay test and fixed frequency Békésy recording. The results of these tests are suggestive of a retrocochlear lesion in chronic alcoholics.

Is there an ototraumatic interaction between noise and solvents?

A review of the literature and four case reports are presented. The patients had all been exposed to noise as well as to organic solvents and they demonstrate a much more pronounced sensorineural hearing loss than would be expected from their noise exposure only. In one of the cases a psycho-organic syndrome due to solvent exposure was verified. Audiograms from 32 painters in a shipyard who had been exposed to noise and solvents did not, however, show any clustering of inexplicably pronounced sensorineural hearing losses. With reference to the above cases it is suggested that there might be a possibility of an ototraumatic interaction between solvents and noise. In view of the neurotoxic effects of organic solvents, such an interaction is conceivable.

Auditory effects of chronic alcoholism

Clinical reports of hearing loss, tinnitus, and auditory hallucinations, as well as empirical studies of auditory phenomena, have sparked interest in the auditory effects of chronic alcoholism. The auditory system, owing to its multi-synaptic course through the central nervous system and to the many techniques available for diagnostic evaluation, affords a special opportunity for examination of transmission breakdown in alcoholics. The present paper reviews several different approaches to the study of disrupted hearing: histologic evidence: threshold measurement, evoked potential data; acoustic reflex studies; and behavioral central auditory evaluation. The review explores effects attributed to both peripheral and central loci, and outlines the ramifications for research and treatment.