What Is Dementia?

If someone suffers from dementia, it may mean they have Alzheimer’s. but not always. When talking about what is dementia, the term covers several conditions.

Dementia is not one, specific disease, but a term that describes a group of symptoms associated with several brain disorders.

So, what is dementia, exactly? When a person is diagnosed with dementia, it means they suffer from failing memory and a decline in thinking skills — problems in cognitive abilities so severe a person’s ability to perform basic, everyday activities becomes limited and, eventually, can become impossible.

In addition to memory problems, dementia negatively affects communication and the ability to focus. Some people with dementia lose control of their emotions and have disturbing personality changes, too.

It’s true that Alzheimer’s disease is the most common cause of dementia, comprising 60 to 80 percent of dementia cases and affecting over five million Americans. But there are many other types of dementia, and some can be potentially prevented and even reversed, according to the Alzheimer’s Association.

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Understanding Alzheimer’s disease dementia

Alzheimer’s disease involves parts of the brain controlling not only memory but thought and language, the Centers for Disease Control and Prevention (CDC) notes. It is an irreversible, progressive and devastating form of dementia that slowly destroys memory and thinking skills and, eventually, even the ability to talk and respond to the environment. In people with the most common form — late onset Alzheimer’s disease — symptoms usually first appear when they reach their mid-60s.

Scientists have learned that abnormal amyloid plagues and tangled bunched fibers know as neurofibrillary, or tau, tangles are some of the main identifying features of Alzheimer’s, along with a loss of normal connections between neurons — brain cells that transmit message between different parts of the brain, according to the National Institute on Aging (NIA).

Although researchers are gaining new insights into what is dementia caused by Alzheimer’s, there is currently no cure. However, some medications can temporarily improve symptoms.

Vascular dementia can be prevented

Vascular dementia results from conditions that block or reduce blood flow to the brain, robbing brain cells of vital oxygen and nutrients. Stroke and other vascular brain injuries are the main causes of vascular dementia. The resulting problems with thinking, memory, and other brain functions can vary in severity depending on the size, location, and extent of brain damage.

Vascular dementia, which is the second most common form of dementia, can begin suddenly and progress — or it can also subside in some cases, the NIA points out. Controlling conditions impacting the health of your heart and blood vessels can often slow any worsening of vascular dementia and can sometimes prevent further cognitive decline.

Although growing older raises the odds you’ll develop the condition, you can take steps to lower the risk of vascular dementia occurring. In fact, the CDC says vascular dementia is preventable.

The reason behind this hopeful assessment is brain health is tied to heart health. And the same strategies to prevent cardiovascular disease may prevent vascular dementia.

Advice from the CDC for preventing heart and vascular problems linked to vascular dementia include keeping your blood pressure under control, losing weight if you are overweight or obese, getting regular exercise, stopping smoking, limiting alcohol use, and eating a nutritious diet.

Preventing type 2 diabetes or keeping it under control with exercise and weight loss, if needed, is also important, because high blood sugar can damage blood vessels and nerves, upping the risk for heart disease, stroke — and vascular dementia.

Other types of dementia

When considering what is dementia, it’s important to note mixed dementia is not uncommon. Mixed dementia refers to more than one type of dementia (most often vascular dementia and Alzheimer’s disease) occurring in the same person.

In addition, there are several other forms of memory-robbing dementia including:

• Lewy body dementia. The third most common type of dementia, this form is associated with abnormal deposits of proteins, known as Lewy bodies. These abnormal proteins disrupt brain chemicals, causing problems with thinking, behavior, and mood, the NIA explains. Lewy body dementia is sometimes initially misdiagnosed as Alzheimer’s or a psychiatric disease. As the disease progresses, other symptoms develop, including movement problems, rigidity, hallucinations, tremors, screaming, and acting out during sleep. On average, people with this form of dementia live five to eight years after symptoms are evident, although some live much longer.
• Parkinson’s disease dementia. Many people living with Parkinson’s disease develop a decline in thinking and reasoning. The brain changes caused by Parkinson’s are linked to Lewy body deposits. Symptoms may gradually spread and impact memory and the ability to pay attention and plan steps needed to complete a task, according to the Alzheimer’s Association. However, not all people with Parkinson's disease develop dementia, and it is difficult to predict who will and how it will progress, the NIA points out.
• Frontotemporal disorders. Frontotemporal disorders are forms of dementia caused by a family of brain diseases known as frontotemporal lobar degeneration (FTLD) that cause parts of the brain associated with language, personality, and behavior (the frontal and temporal lobes) to shrink. This progressive damage causes difficulties in thinking, emotional problems, and trouble communicating. Some people with the disease may eventually be unable to walk, too. Unlike most other forms of dementia, FTLD often develops at a young age, typically between 40 and 45. The National Institute of Neurological Disorders and Stroke (NINDS) estimates FTLD may cause up to 10 percent of all cases of dementia. The course of the disease is difficult to predict for each patient, according to the NINDS, but it is incurable and progressive, although some people may live up to 10 years with this form of dementia.

Dementia is frightening — but there is hope

There’s no doubt dementia continues to destroy millions of lives and is often incurable. However, the CDC emphasizes mental decline and dementia are not inevitable, normal parts of aging — and scientists are making progress unraveling the causes of Alzheimer’s disease and other forms of dementia and working on potential treatments.

In the meantime, it makes sense to be proactive about your health to hopefully lower your risk of dementia. In fact, evidence has mounted in recent years a healthy lifestyle, including regular exercise and a nutritious diet, can play a significant role in preventing dementia.

What’s more, some symptoms of dementia may actually be the result of medical problems that can be treated successfully to reverse memory loss and mental confusion. For example, side effects to certain drugs, thyroid problems, vitamin B12 deficiency, and severe depression can all present with signs that suggest dementia but are, instead, treatable, the Alzheimer’s Association points out.

Bottom line: It’s important to talk to your doctor if you or anyone in your family shows symptoms of a declining or confused memory.

If you are diagnosed with Alzheimer’s or another form of dementia, you can start on medications to improve symptoms for as long as possible. An early diagnosis may make you eligible for a wide variety of clinical trials, too, which can advance research and may provide medical benefits. You can also work with your doctor on healthy lifestyle changes to help preserve your cognitive reserve for as long as possible, the Alzheimer’s Association explains.

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