Clinical Findings That Differentiate Co-Occurrence of Hyperacusis and Tinnitus from Tinnitus Alone

Abstract

Purpose We aimed to assess the characteristics of patients with concurrent tinnitus and hyperacusis, determine the best audiological criteria for predicting hyperacusis, and confirm whether objective evidence of changes in the brain exists. Materials and Methods The medical records of patients with tinnitus who visited the hospital between March 2020 and December 2021 were reviewed. Data on accompanying hyperacusis, audiological profiles, and questionnaires including the Tinnitus Handicap Inventory (THI), Beck Depression Inventory, and numerical rating scale were analyzed. Resting-state quantitative electroencephalography (qEEG) using power spectral density (PSD) and event-related spectral perturbation (ERSP) were performed to objectively quantify changes in the brain. Results A total of 194 patients were analyzed. Among them, 51 (26.3%) reported combined subjective hyperacusis with tinnitus. However, the proportions widely varied from 7.4% to 68.4% based on three audiological criteria for assessment. A higher score on the THI questionnaire was independently associated with the co-occurrence of tinnitus and hyperacusis. Fair agreement was observed between subjective hyperacusis and the audiological criterion based on a loudness discomfort level (LDL) of ≤90 dB at two or more frequencies for the diagnosis of hyperacusis. An increased beta-PSD and decreased levels of gamma-PSD, all-ERSP, and delta-ERSP were observed in patients with hyperacusis ( p <0.05). Conclusion Patients with co-occurring tinnitus and hyperacusis had more severe tinnitus distress. An LDL of ≤90 dB at two or more frequencies may be applicable to predict accompanying hyperacusis in subjects with tinnitus, and qEEG also provides more objective information.

Audiological and psychological assessment of tinnitus patients with normal hearing

“…As described above, decreased LDL was the most common abnormal finding in this study. Similar to this study, in our previous study with 194 tinnitus patients, 26.3% had subjective symptoms, and 68.4% also showed lower LDL by the same criteria ( 7 ). Therefore, we assumed that hyperacusis is not a unique symptom observed only in tinnitus patients with normal hearing but seems to be a common symptom in tinnitus patients regardless of the hearing level.…”

“…Patients with concomitant tinnitus and hyperacusis complained of more severe tinnitus distress, and a criterion for the co-occurrence of LDL ≤ 90 dB at two or more frequencies can be applied to predict accompanying hyperacusis ( 7 ). As described above, decreased LDL was the most common abnormal finding in this study.…”

“…A threshold exceeding 30 dBnHL was defined as an increased threshold of wave V of ABR ( 29 ). Decreased LDL was defined as LDL ≤ 90 dB at two or more frequencies ( 7 ). Increased SP/AP ratio was defined as a ratio ≥0.4 ( 30 ).…”

“…A recent review highlighted the role of the triple network in tinnitus distress ( 6 ). Tinnitus distress is also aggravated by accompanying hyperacusis ( 7 ). Taken together, these findings suggest that various changes in the auditory, emotional, and somatosensory systems may be involved in the generation and maintenance of tinnitus.…”

“…Taken together, these findings suggest that various changes in the auditory, emotional, and somatosensory systems may be involved in the generation and maintenance of tinnitus. These changes include decreased loudness discomfort level (LDL), extended high-frequency hearing loss (EHFHL), increased summating potential (SP)/action potential (AP) ratio, decreased distortion product otoacoustic emission (DPOAE), altered wave V thresholds of auditory brainstem response (ABR), somatic modulation, and accompanying psychiatric symptoms ( 4 , 7 – 28 ). In addition, various subclinical auditory dysfunctions may be hidden.…”