Memory loss is the first symptom of dementia. Other symptoms of dementia include difficulty remembering recent events, difficulty finding the right words, problems regulating emotions, an inability to use good judgment when needed, and a lack of personal hygiene, according to WebMD.
Falling, hallucinations and personality changes are less common symptoms of dementia, notes WebMD. Some of these symptoms overlap with symptoms of depression and other disorders.
Common causes of irreversible dementia are Parkinson's disease, dementia with Lewy bodies, frontotemporal dementia and severe head injury, adds WebMD. Vascular dementia and Alzheimer's disease are the most common causes of irreversible dementia. Patients presenting symptoms of early-onset Alzheimer's are likely to have an inherited form of the disease. Late-stage syphillis, multiple sclerosis or amyotrophic lateral sclerosis, leukoencephalopathies and Huntington's disease are rarer causes of irreversible dementia.
Some forms of dementia are reversible if there is a treatable cause, advises WebMD. Vitamin deficiencies, heavy metal poisoning, hypothyroidism, alcoholism and encephalitis are treatable causes of dementia. HIV/AIDS is another treatable cause.
People who suffer from diabetes, high blood pressure, high cholesterol or atherosclerosis have an increased risk of vascular dementia, notes WebMD. Older adults have the highest risk of developing symptoms of dementia. Men also have a higher risk of developing symptoms.