Depression sometimes presents with forgetfulness and memory loss. Lethargy is also associated with Alzheimer's Disease. Of course all these are also associated with aging. There are several brain syndromes that mimic Alzheimer's Disease. Parkinson's Disease has some similarities to Alzheimer's Disease, but it affects movements, walking, hand-coordination, and sometimes speech, more often. Other conditions like Senility are confused with Alzheimer's and may be as debilitating. The difference may lie in the symptoms and potential remedies.
Both Parkinson's and Alzheimer's Diseases have support organizations that offer aid to victims and family members and support research into the causes and cures. For more information about Alzheimer's Disease click this link. To learn more about Parkinson's Disease click link Parkinson's Disease