Silence of the Strands: Unveiling the Link Between Alopecia Areata and Sensorineural Hearing Loss

Original Article: Association of Alopecia Areata with Sensorineural Hearing Loss: A Systematic Review and Meta-Analysis

What are the key takeaways of this article?

In the vast field of dermatology, intriguing discoveries often emerge from the intricate web of connections between various conditions. One such captivating link that has recently captured the attention of researchers revolves around the enigmatic relationship between alopecia areata (AA) and sensorineural hearing loss (SNHL). AA is an autoimmune condition that results in sporadic, patchy hair loss compared to the more common hair loss condition, androgenic alopecia (a well-defined pattern of hair loss). SNHL is hearing loss caused by damage to the inner ear or the auditory nerve. Melanocytes, which are targeted in AA, play a role in maintaining the inner ear's function, including regulating auditory signal transmission and neutralizing harmful substances. Thus, the auto-immune destruction of melanocytes within the inner ear is a possible explanation for the connection between AA and SNHL.

To determine if a relationship between AA and SNHL exists, the authors of the article conducted a systematic review and meta-analysis of relevant studies. The systematic review included cross-sectional, case-control, and cohort studies from MEDLINE and Embase that examined the association of AA with SNHL. The key experiments and findings involved a meta-analysis of five case-control studies and one cohort study. The researchers utilized a random-effects model meta-analysis to determine the mean differences in hearing thresholds between AA patients and healthy controls, as well as the odds ratio for SNHL in relation to AA.

The main conclusions of the study indicate that there is a significant association between AA and SNHL, particularly at high frequencies. The meta-analysis revealed that AA patients exhibited elevated mean differences in pure-tone hearing thresholds at 4000 Hz and 12000-12500 Hz, signifying potential hearing impairment. Moreover, the odds for SNHL were also increased among AA patients, with 3.18-fold higher odds than controls. Significant elevations in hearing thresholds were primarily observed at higher frequencies, while the range where most daily conversations occur showed a significant difference only at 4000 Hz. While the included studies do not establish a significant association between the severity or duration of AA and SNHL, it is important to note that the subjects studied exhibited relatively low severity and a short mean duration of AA.

In conclusion, this study provides evidence of a significant association between AA and SNHL, with a particular emphasis on the impact at higher frequencies. While further research is required to establish a direct causal relationship between AA and inner ear damage, these findings have profound implications for dermatologists and otolaryngologists alike. The findings emphasize the importance of considering hearing loss or tinnitus in AA patients, particularly at the initial presentation when high-frequency SNHL might be the only noticeable symptom. The article suggests consulting with otolaryngologists when AA patients complain of hearing loss or tinnitus to ensure appropriate evaluation and management.

Publication Date: July 9th, 2023

Reference: Kuang-Hsu Lien, Tzong-Yun Ger, Ching-Chi Chi; Association of Alopecia Areata with Sensorineural Hearing Loss: A Systematic Review and Meta-analysis. Dermatology 2023; https://doi.org/10.1159/000530784

Summary By: Sascha Azoulay