Would it be possible for someone to die from alzheimer's disease or not?

Yes/no: Alzheimer's disease, per se, is not what kills people. It is typically an infection - like pneumonia or a dessiminated infection from bed sores, or simply cardiovascular collapse from old age. The brain damage, as far as i know, does not shut down critical deep brain mechanisms which are required to sustain life, but it (tragically) robs one of cognitive awareness and that which makes us human.