There is a greater prevalence of hearing loss among alopecia areata patients compared to healthy controls, which can be attributed to the involvement and destruction of follicular melanocytes.
Alopecia areata (AA) is characterized by the autoimmune destruction of hair follicles. The autoimmune process may also involve the follicular melanocytes, eventually leading to hearing changes in AA patients.
This cross-sectional study evaluated the hearing changes in AA patients compared to healthy controls. The findings are published in the Indian Journal of Dermatology, Venereology, and Leprology.
Baseline Characteristics
A total of 42 AA patients and 42 healthy individuals were recruited after the clinical diagnosis of the disease. The Severity of Alopecia Tool mean score was utilized to evaluate the severity of AA, estimated to be 41.13 ± 18.76 out of a 100-point scale. Twenty-two subjects had patchy hair loss, whereas 20 subjects had total alopecia. The mean duration of the disease was 4.11 ± 3.24 years. Two AA patients also reported nail involvement.
Auditory Test Results
According to the vestibular evoked myogenic potential (VEMP) test, normal response, unilateral involvement, and bilateral involvement were observed in 81%, 14.3%, and 4.8% of patients, respectively. There were no significant differences across healthy controls and AA patients for the amplitude and latency values of the VEMP test.
The otoacoustic emission (OAE) test indicated that 17 AA patients did not demonstrate a normal response, with left ear and bilateral involvement in six and 11 patients, respectively. The pure tone audiometry (PTA) test results were normal in 76.2% of AA patients, and the frequency corresponding to the greatest hearing loss was 4000–8000 Hz.
Speech Recognition Threshold
There was no significant difference across the case and control groups for the most comfortable speech values. The mean speech recognition threshold for healthy controls and AA patients was 12.02 ± 2.48 and 12.26 ± 4.71, respectively. In addition, the mean speech discrimination score values in healthy controls and AA patients were 97.7 ± 2.75 and 99.40 ± 1.97, respectively. The AA patients demonstrated significantly higher speech discrimination scores and mean speech recognition thresholds.
Differences in the Hearing Threshold
There was no significant difference in hearing thresholds between healthy controls and AA patients for frequencies of 250 Hz and 500 Hz in the right ear and 1000 Hz in the right and left ears. Conversely, there was a significant difference in the hearing thresholds of healthy controls and AA patients for frequencies of 250 Hz in the left ear and 2000 Hz, 4000 Hz, and 8000 Hz in both the right and left ears.
The involvement and destruction of follicular melanocytes in AA patients result in impaired hearing function; however, hearing loss is not significantly associated with the severity and duration of AA.
Source
Shakoei, S., Mohammadnia, E., Saedi, B., Ghandi, N., & Khamisabadi, S. (2023). Hearing impairment in patients with alopecia areata. Indian Journal of Dermatology, Venereology and Leprology, 0, 1–5. https://doi.org/10.25259/ijdvl_416_2022
