http://content.nejm.org/cgi/content/short/338/3/171 (you may have trouble accessing this article).
http://www3.interscience.wiley.com/journal/120755487/abstract?CRETRY=1&SRETRY=0 (This is the abstract)
http://psychservices.psychiatryonline.org/cgi/content/full/54/9/1223 (cognitive decline resulting from stress)
There's heaps of stuff around now on the damage which stress can do to the immune system. I can't think of anything off the top of my head but I'll do a Google search and see what I come up with that might interest you. How much technical medical jargon can you cope with?