When depression occurs in late stages of Alzheimer's, the person may be combative or agitated and may often refuse food and drink. Depression makes brain function much worse than it otherwise would be, but treatment is available and effective. There is no cure for Alzheimer's. The goal of treatment is to preserve mental and physical function as much and as long as possible. The best approach seems to include control of other illnesses, good nutrition, regular exercise, and appropriate activities.
Medication is sometimes helpful.
Both of these medications are expensive and have side effects that can be difficult to tolerate. Community resources are very important. They also provide home health aides for personal care. The brain function of a person who has Alzheimer's disease continues to get worse until the person dies. Death may occur after as few as 3 years or as long as 20 years after the disease is diagnosed.