The problem as I see it, is that as we age the wear and tear on our bodies, accumulates. People with fibro, and those without both have symptoms of wearing out joints, aging cell tissue. I personally believe there is a deficiency of Human Growth Hormone and other important hormones diminishing as we age, and the HGH is what helps cells heal. So, we don't "heal normally". Therefore, as we age, there is more wear and tear, we don't heal as well, therefore, progression. I don't know about
the fatality bit.