Alopecia Areata Linked to Sensorineural Hearing Loss

Alopecia areata (AA) is associated with sensorineural hearing loss (SNHL), especially at high frequencies, according to a study in Dermatology.

Researchers conducted a systematic review and meta-analysis to evaluate the evidence of the association of AA with SNHL. They searched the MEDLINE and Embase databases for relevant articles from inception until July 25, 2022.

Inclusion criteria for the review included observational studies assessing the association of AA with hearing loss, including cross-sectional, case-control, or cohort studies. The non-AA comparison group was composed of age-matched control individuals. The study excluded participants with previous ototoxic drug use, otologic surgery, chronic noise exposure, otologic pathology, head trauma, or any other neurologic or vascular disease.

The analysis included 5 case-control studies and 1 cohort study with a total of 55,419 participants. All the studies included sex- and age-matched control individuals, and the risk of bias was generally low. The participants had a disease duration of 2.9±4.6 to 18.7±39.5 months.

Pure-tone threshold (PTT) data were reported in 4 case-control studies at specific frequencies from 250 to 8000 Hz, and 2 studies included extended high frequencies  over 8000 Hz.

The PTTs of the AA and control groups were not significantly different at 250 Hz (mean difference [MD], 1.23; 95% CI, -1.03 to 3.49; I², 67%), 500 Hz (MD, 1.59; 95% CI, -0.73 to 3.92; I², 58%), 1000 Hz (MD, 1.03; 95% CI, -0.20 to 2.25; I², 0%), 2000 Hz (MD, 1.08; 95% CI, -0.43 to 2.60; I², 0%), and 8000 Hz (MD, 1.53; 95% CI, -0.96 to 4.01; I², 0%), respectively.

Among the AA and control groups, PTTs were significantly different at 4000 Hz (MD, 2.96; 95% CI, 0.63-5.29; I², 0%) and 12,000 Hz to 12,500 Hz (MD, 10.26; 95% CI, 5.41-15.12; I², 0%).

The participants with AA had increased odds for SNHL (odds ratio [OR], 3.18; 95% CI, 2.06-4.89; I², 0%). A sensitivity test of 3 case-control studies with 131 participants with AA and 125 control individuals also demonstrated significantly increased odds of SNHL in the participants with AA (OR, 2.55; 95% CI, 1.40-4.66; I², 0%).

Limitations of the study include the fact that otoacoustic emissions to evaluate hearing in participants with AA were not calculated owing to the absence of complete and standardized data. In addition, confounders may exist, and no consistent criteria were applied, such as the Severity of the Alopecia Tool (SALT) and SALT II.

The researchers conclude, “Consultation with otolaryngologists may be needed when AA patients complain of hearing loss or tinnitus. Further investigation especially direct evidence of AA influencing inner ear is still needed to support our findings.”