Why is Outlook taking over my CPU??!?!?!?

Arggh.  Anyone, please help. 

I have having this problem on my Latitude laptop where after launching my MS Outlook email here at work, within anywhere from 1 to 30 minutes the CPU is max'd out at 100% and MS Outlook freezes up at that point.  I have to restart to resume work with email.

This does NOT happen if Outlook is not running.  Anyone here of anything like this??  I verified that both the SOBIG and SASSER viruses are not on the machine.  I also installed a couple of anti-adware / spyware programs, so I don't think those are causing the problem. 

What can I do to avert this issue?

Thanks!