Why Jimmy Sullivan (the Rev) died?

I’m sure lots already know about how the drummer of Ax7 died in December. Does anyone know why he died or what could have caused it? I have only heard of natural causes, which at his young age doesn’t make much sence. Was anyone else upset when they heard about his death if so what did you do about it? I myself coped with it buy listening to their music and became suddnly interested in learning more about famous peoples lifes so bought a few autobiographys to read.