Dementia is a medical condition that interferes with the way the brain works. Symptoms include anxiety, paranoia, personality changes, lack of initiative, and difficulty acquiring new skills. Besides Alzheimer’s disease, some other types or causes of dementia include: alcoholic dementia, depression, delirium, HIV/AIDS-related dementia, Huntington’s disease (a disorder of the nervous system), inflammatory disease (for example, syphilis), vascular dementia (blood vessel disease in the brain), tumors, and Parkinson’s disease.
Alzheimer’s disease is the most common form of dementia. It proceeds in stages over months or years and gradually destroys memory, reason, judgment, language, and eventually the ability to carry out even simple tasks.
Delirium is a state of temporary but acute mental confusion that comes on suddenly. Symptoms may include anxiety, disorientation, tremors, hallucinations, delusions, and incoherence. Delirium can occur in older persons who have short-term illnesses, heart or lung disease, long-term infections, poor nutrition, or hormone disorders. Alcohol or drugs (including medications) also may cause confusion.
Delirium may be life-threatening and requires immediate medical attention.
Depression can occur in older persons, especially those with physical problems. Symptoms include sadness, inactivity, difficulty thinking and concentrating, and feelings of despair. Depressed persons often have trouble sleeping, changes in appetite, fatigue, and agitation. Depression usually can be treated successfully.
Source: Agency for Health Care Policy and Research (AHCPR)
Publication No. 96-0704
Clinical Practice Guideline, Number 19, Consumer Version