Dementia is an umbrella term for conditions that impair a person’s ability to think, reason and remember to levels that interfere with daily life. Although the risk of dementia rises a great deal after age 65, it is not an inevitable part of aging. It’s important to know it’s a disease; it’s not just normal aging or getting old. Dementia can be caused by several different diseases, including Alzheimer’s. At the core of any dementia, brain cells die. In the early stages, a person initially can compensate, by using labeled pillboxes, for example, or keeping notes, and often still can function. But gradually — often over years — the person begins to have trouble doing things for themselves.
Alzheimer’s disease is by far the most common form, causing 60 to 80 percent of dementia cases, according to the Alzheimer’s Association. But there are other forms, each with different causes and sometimes strikingly different symptoms. These include vascular dementia, Lewy body dementia and frontotemporal dementia. Some people can suffer from a combination of two or more of these, a condition known as mixed dementia. What these illnesses have in common is that they result from a progressive destruction of brain cells, affecting thinking, memory and behavior in various ways.
Dementia is not the same as mild cognitive impairment, or MCI, an early stage of memory and cognitive loss not serious enough to impair a person’s daily activities. Some people with MCI — 10 to 15 percent — will progress to full-blown dementia each year. Others will not.
With Alzheimer’s, people “have trouble remembering the answers to questions, so they end up asking them again and again and again. Other times, patients with Alzheimer’s can have false memories. For example, someone could have watched a TV show about going on a trip to Europe, then tell their family they went on this wonderful trip to Europe.
Dementia in its various forms can impair judgment, affect mood and personality, prompt odd behavior and distort how a person perceives what he or she sees. Occasionally forgetting a name or misplacing a set of keys is normal as we age. The deficits associated with dementia are greater, and more devastating, since they seriously affect how a person lives and functions.
What causes dementia?
Dementia occurs when neurons, or nerve cells, in the brain quit working. They lose their connection to other brain cells and eventually die. We all lose neurons as we age, but the loss is much greater in dementia. Some risk factors for dementia, such as age and genetics, are impossible to change. But there are other factors that you can act upon — including diet and exercise, hearing loss and social isolation.
How is dementia diagnosed?
There is no single diagnostic test to say whether a person has dementia. So doctors use a variety of tests and tools to learn what’s going on with the patient, look for signs of disease and, most importantly, rule out other treatable conditions that may be causing the cognitive problems. Brain scans may be used, as well as other tests — on blood and spinal fluid — to detect changes within the brain and identify the presence of certain substances associated with dementia. Paper-and-pencil or computer-based tests of memory and thinking are also often used to help make a dementia diagnosis.
Reducing risk for dementia
Researchers say there are things you can do to reduce your risk, along with avoiding head injuries and maintaining hearing. These include stopping smoking, eating a healthy Mediterranean-style diet and exercising, controlling diabetes and managing heart disease risks, such as high cholesterol and hypertension.
