Laterality of sudden sensorineural hearing loss

Area of Science:

• Otolaryngology
• Neuroscience
• Epidemiology

Background:

• Sudden sensorineural hearing loss (SSNHL) and other otoneurologic conditions like Ménière disease exhibit a known left-ear predominance.
• The underlying reasons for this lateralization in SSNHL remain largely unelucidated.
• Understanding laterality patterns can offer insights into disease mechanisms and potential risk factors.

Purpose of the Study:

• To investigate the lateralization patterns of sudden deafness in a patient cohort.
• To determine if there are sex-specific differences in the laterality of sudden deafness.
• To explore potential contributing factors, such as hormonal influences, for observed asymmetries.

Main Methods:

• Retrospective analysis of 489 patients diagnosed with sudden deafness between January 2004 and December 2009.
• Data collection included patient demographics and affected ear side (left vs. right).
• Statistical analysis to compare the frequency of left-sided versus right-sided sudden deafness, stratified by sex.

Main Results:

• A male-to-female ratio of 1:1.24 was observed in the study population.
• A statistically significant predominance of left-sided sudden deafness was identified exclusively in female patients.
• No significant left-sided predominance was noted in male patients.

Conclusions:

• The findings suggest a potential sex-specific vulnerability of the left inner ear in women regarding sudden deafness.
• Hormonal factors may play a role in the pathogenesis of sudden sensorineural hearing loss, particularly in females.
• Further research is warranted to confirm these findings and elucidate the precise mechanisms behind sex-based lateralization in SSNHL.