Signposts for depression

To detect depression in people who have Alzheimer's disease, doctors must rely more heavily on nonverbal cues and caregiver reports than on self-reported symptoms. If a person with Alzheimer's displays one of the first two symptoms in this list, along with at least two of the others within a two-week period, he or she may be depressed.

• Significantly depressed mood — sad, hopeless, discouraged, tearful
• Reduced pleasure in or response to social contacts and usual activities
• Social isolation or withdrawal
• Eating too much or too little
• Sleeping too much or too little
• Agitation or lethargy
• Irritability
• Fatigue or loss of energy
• Feelings of worthlessness, hopelessness or inappropriate guilt
• Recurrent thoughts of death or suicide