What is the author's style in I Know This Much Is True by Wally Lamb?

I Know This Much Is True the incorporates reflections of a deeply embittered college-educated man seeking to understand his dysfunctional family and deliver his paranoid schizophrenic twin brother from a brutal and politically-motivated bureaucracy. It is filled with narrator Dominick Birdsey's intense fear, angst, frustration, and rage. His mentally afflicted brother has become a "holy-roller," quoting scripture as his motivation for cutting off his right hand, and railing against conspirators, including President George W. H. Bush, the CIA, the FBI, and even the manufacturers of Special K cereal. He is Jesus' new Simon Peter, determined to warn the world of Armageddon.