What is Dementia?

Dementia is a general term describing a category of diseases that result in impairment of memory, language, personality, behavior and judgment, along with a decline in physical functions such as self-care, continence, and mobility. Dementia can be caused by several different illnesses or conditions, the most common type being Alzheimer's disease. Studies estimate that 12% of people 65 years and older, and nearly half of persons 85 years and older, are now affected by dementia . Currently, Alzheimer's disease affects 5.1 million Americans. With the increasing number of older adults in our society, 11.3 million to 16 million Americans could have the disease by 2050.

There are many types of dementia. The four most common types are:

  • Alzheimer's disease is the most common form of dementia accounting for 50-60% of all dementias. It is typically characterized by gradual onset of memory loss followed by a continued decline in other areas of mental, and eventually physical, functioning. Common losses begin with difficulty in managing everyday activities, followed by the ability to care for oneself. Verbal communication gradually decreases over time, along with the abilities to walk and control bowel and bladder. The greatest risk factor for Alzheimer's disease is advanced age.
  • Lewy Body Dementia is a form of dementia that shares symptoms of both Alzheimer's and Parkinson's disease. Lewy body dementia is characterized by gradual onset and fluctuating mental alertness/abilities, along with physical symptoms of Parkinson's (such as a shuffling walk or tremors). Vivid visual hallucinations, brief periods of unexplained loss of consciousness, repeated falls, sleep disturbance, and sensitivity to some anti-psychotic medications may occur.
  • Vascular dementia, often in combination with Alzheimer's, is a deterioration of mental function caused by multiple strokes (infarcts) in the brain. The onset may appear sudden, depending on the size and location of the stroke. Although Vascular dementia is not reversible, treatment of risk factors, particularly high blood pressure, may modify or slow the progression. Losses in function, memory, and language may appear much like Alzheimer's, although; due to continued strokes, sudden changes may be more evident.
  • Frontotemporal dementia is characterized by two clinical patterns: changes in behavior and problems with language. Initial symptoms often include uninhibited or inappropriate social behavior, which loved ones and caregivers may find very distressing. The person with Frontotemporal dementia may appear apathetic and/or lack insight into the consequences of their actions. Spatial skills and memory usually remain relatively intact. Frontotemporal dementia typically occurs between the ages of 35 and 75, and family history is a risk factor.

Diagnosis

Diagnosis of dementia involves a careful history, review of symptoms, and thorough physical exam, which may include blood work, head scans and neuropsychological testing. These measures provide information that helps to rule out treatable conditions that may cause memory impairment including depression, medication side effects, thyroid conditions, problems with vision and hearing, excess use of alcohol and nutritional imbalances.

Clinicians specializing in memory disorders are now able to diagnose Alzheimer's disease with greater than 90% accuracy. Still, brain autopsy remains the only way to definitively confirm that an individual had Alzheimer's disease or another type of dementia. Arrangements for brain autopsy should be set up well in advance of the person's death. For further information, speak with your healthcare provider or social worker.

Treatment

Treatment of dementia is limited, and currently, there is no cure. However, two classes of medications approved to treat Alzheimer's disease appear to provide some benefit in certain patients. The first class of medications is cholinesterase inhibitors [donepezil (Aricept), rivastigmine (Exelon), galantamine (Razadyne)]. The second class, NMDA receptor antagonists, currently includes one drug called memantine (Namenda). These medications may slow the course of disease by about six to twelve months in 30%-50% of patients.

Progression

Progression of dementia can vary according to the type. Life expectancy can range from two to 20 years, the average being four to six years after diagnosis. Because dementia progresses through the brain, physical and mental functions are affected, such as thinking, memory, self-care abilities, continence and mobility.

By the advanced stage, people with dementia usually have lost the ability to communicate verbally, walk independently, control bladder and bowel function and participate in self-care. At this stage, hospice care can be very beneficial for both the patient and the family. The focus is on comfort and quality of life. Infection, such as pneumonia, is the most common cause of death.