For disabled adults:
There is an extra amount added to your standard deduction if you are legally blind. Your federal return does not provide any other credits or deductions for saying you are disabled, with one possible exception.
There is a credit for the Elderly and Disabled which is so small that very few people benefit from it—-it has not been updated/increased by Congress for decades.
ELDERLY OR DISABLED CREDIT https://www.irs.gov/help/ita/do-i-qualify-for-the-credit-for-the-elderly-or-disabled
There are some states that provide various credits to elderly/disabled folks, so watch for that when you prepare your state return. The states that I know of that have anything for elderly/disabled are AZ, CT, DE, IA, MO, ND, NY, VE. There may be others.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**