My wife works for the state as a Nurse Practitioner Supervisor and she requires a hearing aid to function. Would her deafness qualify as a disability?

[Vanessa]

If you are asking if she can deduct this as a job-related expense, no.  Only special accommodations for someone to do their job would be deductible.

This would be deductible as a medical expense because it is a general health/hearing requirement and is used more than incidentally in her personal activities.

"You can deduct impairment-related expenses as business expenses if they are: 

•  Necessary for you to do your work satisfactorily; 
• For goods and services not required or used, other than incidentally, in your personal activities; and 
•  Not specifically covered under other income tax laws." https://www.irs.gov/pub/irs-pdf/p463.pdf