This page is take from the Independent Lives website as it explains DRE very well

When starting out on a Direct Payment, your Local Authority will give you a financial assessment to see how much they will ask you to pay towards your care. This is called the Client Contribution.

In order to reduce the amount you have to pay for your care, your Local Authority should take into account any Disability Related Expenses (DRE) you have, which they should disregard as available income, reducing the amount of your client contribution.

Disability Related Expenses are any extra costs linked to any disability you have.

Read more here:

https://www.independentlives.org/disability-related-expenses-explained