Seasonal Variation in Autoimmune Inner Ear Disease: A Preliminary Study

To determine whether there is seasonal variation in the audiogram data of patients with autoimmune inner ear disease (AIED).

Retrospective chart review.

Academic.

One hundred forty-one adult patients with a diagnosis of AIED from January 2010 to June 2023 were included.

Audiometry.

For patients' better- and worse-hearing ears, as defined by audiogram metrics, pure tone average (PTA), high-frequency PTA (HFPTA), low-frequency PTA (LFPTA), and average word discrimination score (WDS) were calculated for each season.

For better-hearing ears, hearing was, on average, 0.9 dB worse in the summer than in the winter (P=0.04). High-frequency hearing was 1.18 dB worse in the spring (P=0.047) and 1.11 dB worse in the summer (P=0.03) compared with the winter. Low-frequency hearing was 0.68 dB worse in the spring (P=0.04) and 0.89 dB worse in the summer (P=0.04) than in the winter. For worse-hearing ears, low-frequency hearing was 1.10 dB worse in the spring (P=0.01), 1.83 dB worse in the summer (P=0.0003), and 1.57 dB worse in the autumn (P=0.005) compared with the winter. WDS showed no significant differences across seasons. However, more patients were found to have "flares," sudden decreases in hearing or increases in subjective symptoms, as indicated by patient complaints and prednisone prescriptions, in the winter compared with other seasons. Control patients showed no seasonal variation. Paired t tests, repeated measures ANOVA, and Bonferroni post hoc tests were used.

AIED audiogram changes and flares may be influenced by complex interactions between environmental factors. The implications of seasonal factors as a consideration in the symptoms and treatment of AIED warrant further study.