disk usage - How to remove unused or outdated folders?

I administrate a multi-user system that has had quite a lot of user turnover. The users who have left us still have a folder in the folder /home. I would like to remove the folders for the users that are no longer with us, but I don't want to have to sort through each and every folder and remove them one by one using '-rm'.

Is there a command to remove folders that have not been accessed in a certain amount of time?

Thanks!