The best way to go, many feel, is to get pneumonia in old age and to die quietly, peacefully. Most are not so lucky and some darn doc will try to treat your pneumonia at age 92 to extend your life for a few weeks in the ICU on a respirator. However, for many, if you outlive heart disease cancer will get you: Why Everyone Seems to Have Cancer.
We don't call it "dying of old age" anymore because we have much better diagnostic tools. Everybody has to die from something or other.