Ronald Reagan shared his diagnosis with Alzheimer's disease publicly in 1994.
Ronald Reagan . While having planned an active post-presidency , in 1994 Reagan disclosed his diagnosis with Alzheimer 's disease earlier that year , appearing publicly for the last time at the funeral of Richard Nixon ; he died ten years later in 2004 at the age of 93 ; Reagan had the second-longest life out of all the presidents ; the current longest lifespan of a president is held by Gerald Ford , who died two years after Reagan .