Expert: Harriet B Jacobster, Au.D. - 10/21/2008

Question
I have been using CPAP for approx 5 years and lately have begun to notice a constant ringing in my ears that persists throughout the day.  Most forums I have visited on this issue discuss a possible hearing loss connection due to elevated noise levels experienced by the CPAP user.  I have begun to wonder if my ringing is caused - not by the noise level of my CPAP (which seems rather innocuous) - but by the constant exposure to differential pressure across the ear drum.  CPAP users experience a nightlong differential of up to 20 cm of H2O (~0.28 psi), depending on their prescription setting.  Are you aware of any studies or would you have an opinion about a possible link based on differential pressure rather than noise level?

Thanks, Gregg  

Answer
Hi Gregg,
Sorry to take so long in answering, but I have been checking into references.  I have yet to see any research on the effect of differential pressure of CPAP and its effect on hearing.  My own educated guess is that this has little effect, since we experience this differential almost on a daily basis anyway and that any effect would be more on the middle ear mechanism rather than the inner ear.  Do you have any other symptoms? I will continue to investigate, as this is an interesting theory, and will notify you if I do find anything.
Hope this helps
Harriet B. Jacobster, AuD
Board Certified in Audiology