Comparison of Pure-Tone Average Methods for Estimation of Hearing Loss Caused by Environmental Exposure to Lead and Cadmium: Does the Pure-Tone Average Method Which Uses Low-Frequency Ranges Underestimate the Actual Hearing Loss Caused by Environmental Lead and Cadmium Exposure?

Abstract

Previous studies have reported that exposure to lead and cadmium can damage the inner ear receptor, which perceives high-frequency sounds. However, few studies have used the pure-tone average (PTA), including high-frequency ranges, for the estimation of hearing loss caused by lead and cadmium exposure. We estimated hearing loss using the PTA test, in low-frequency, speech frequency, and high-frequency ranges and compared the differences in the results using 3 PTA calculation methods. We analyzed the data of 2,387 participants, between the ages of 19 and 85 years, that were obtained from the Korea National Health and Nutrition Examination Survey (KNHANES) of 2010–2012. A dose-response relationship between hearing loss and heavy metal exposure was observed in the high-frequency method after adjustment for confounding factors. When using the high-frequency PTA, it was found that doubling of the levels of lead and cadmium in the blood was associated with a 1.88- (95% CI 1.11–3.17) and 1.89-fold (95% CI 1.02–3.50) increase in the OR for hearing loss. In the case of the low-frequency and speech frequency PTA, however, there were no significant relationships between hearing loss and the concentrations of lead and cadmium in the blood. The outcomes of the present study suggest that the estimation of hearing loss caused by environmental exposure to lead and cadmium is affected by the frequencies used in the PTA calculation.

Progression of Contralateral Hearing Loss in Patients With Sporadic Vestibular Schwannoma

“…Given that splitting the VS patients by age, sex or tumor size showed no significant difference in SNHL progression, none of these subgroups seem to be confounders for contralateral hearing loss progression. Directionality and significance of results are shown to be consistent regardless of whether three-or fourtone PTA is used as the primary metric for threshold hearing; this finding is particularly valuable given that three-tone PTA measurements are most closely associated with speech reception thresholds, and thus of highest clinical utility, while mechanisms for progressive SNHL can often first affect only higher-threshold frequencies (36,37). The high degree of alignment in outcomes, regardless of PTA metric used, supports the clinical value of using either three-or four-tone PTA metrics to assess contralateral hearing in VS patients.…”

Sporadic Vestibular Schwannoma Size and Location Do not Correlate With the Severity of Hearing Loss at Initial Presentation

“…High-frequency PTA was determined using thresholds at 3 kHz, 4 kHz, and 6 kHz. Low-frequency PTA was determined using thresholds as 0.5 kHz, 1 kHz, and 2 kHz ( 17 , 18 ).…”

Measuring health-related quality of life in chronic otitis media in a Chinese population: cultural adaption and validation of the Zurich Chronic Middle Ear Inventory (ZCMEI-21-Chn)

“…The pure-tone average (PTA) at speech frequency (0.5 kHz, 1 kHz, 2 kHz, and 4 kHz) [28] were collected from the patient's concurrent audiometry testing. Criteria validity of ZCMEI-21-Chn was assessed with correlations to the PTAs of worse-and better-hearing ear.…”