well, now that fiddling with FS has been mentioned, its quite safe and does not really take away anything you need, to remove atime. There are other settings that may also help but I would be less enthusiastic if its not a specialist mount for just one purpose. But, atime is easy and safe, Windows users for example don't have an atime available any way.
Edit, as root, /etc/fstab, your home dir will probably be like -
UUID=a748839c-84fb-40cc-9b5b-caa902ab00ad /home ext4 defaults 0 2
Add 'noatime', ahead of 'defaults', no space between. Remount, easiest way to do that is reboot if you can.
UUID=a748839c-84fb-40cc-9b5b-caa902ab00ad /home ext4 noatime,defaults 0 2
It will make a difference, I just don't know how big a difference !
Davo