Meteorological Factors in Idiopathic Sudden Sensorineural Hearing Loss: A Retrospective Study

Idiopathic sudden sensorineural hearing loss (ISSNHL), which is an otologic emergency characterized by rapid-onset inner-ear hearing loss without an identifiable cause, remains a clinically urgent but poorly understood entity. While environmental factors have been proposed as potential triggers, prior studies show conflicting results. This study aimed to examine associations between weekly ISSNHL incidence and meteorological variables, including temperature, wind speed, and atmospheric pressure, in a Mediterranean city over a six-year period.

We retrospectively analyzed 97 ISSNHL cases treated at the University General Hospital of Patras, Greece, from January 2019 to May 2025. Daily weather data were averaged into weekly values and aligned with weekly ISSNHL incidence. Welch's t-tests and Mann-Whitney U-tests were used to compare weather variables between high-incidence (weeks with >1 case) and low-incidence periods. Lag models were used to assess delayed effects.

No significant seasonal trend in ISSNHL was detected (p=0.973). However, lower wind speeds were consistently associated with higher ISSNHL incidence (p<0.05 across multiple comparisons). A trend toward lower atmospheric pressure in high-incidence windows was also observed. Temperature showed no significant relationships with ISSNHL.

In this Mediterranean setting, ISSNHL incidence was not seasonally patterned but was associated with low wind speed and possibly low atmospheric pressure in the days preceding onset. These findings suggest that calm atmospheric conditions may contribute to ISSNHL risk, potentially via mechanisms involving air quality, vascular reactivity, or inner-ear pressure dynamics.