Why should it matter what he died from? Luther Vandross suffered a massive stroke April 2003 and had lain with the effects of it undiscovered for 8 hours. He had lost his ability to walk, to speak etc. Complicating matters, he was diabetic and hypertensive. When he made an appearance on the Oprah Show months before his death, he had severely slurred speech ( worse than Dick Clark's) Debilitating strokes also have the effect of making the person severely depressed.