Lightroom >> Preferences >> Performance
Then disable GPU acceleration.
LR will then just work from the CPU and that seems to make a difference to some users.
Also launch Creative Cloud, and go to the Apps tab to ensure you are up to date.
I am having this same problem since the latest Lightroom update back in March 2016. Ver 1067055. Light Room crashes within a few minutes of working with it. I have to reset the PRAM to get the Mac to stop crashing in other programs. I went in LR and disabled the GPU acceleration. I am running El Capitan, ver 10.11.4 on a MacBook Pro (Retina, 13-inch, Early 15, 2.9 GHz Intel i5, 8 GB of RAM, Graphics Intel Iris Graphics 6100 1536 MB, I talked with Apple and checked out the computer. Everything else works fine.
I found a solution to Light Room crashing on my Mac Book. I went to Finder, selected the Light Room file, then Command I, There is a box to open in Low Resolution and I checked it. I used Light Room for several hours with no crashes.