Dementia Care

Alzheimer's Disease

Alzheimer's disease is a progressive neurodegenerative disease that affects the memory and other cognitive functions. Currently ranked as the sixth leading cause of death in the United States overall, it is the third leading cause of death among the elderly. This difficult disease affects roughly 5.7 million Americans, and that number is expected to climb to 14 million by the year 2050.

Though some changes in memory and cognition are a natural consequence of aging, Alzheimer's disease is not a normal part of aging. In its early stages, symptoms typically include mild confusion and changes in memory. Over time, these symptoms worsen and physiological changes in the brain cause the patient to lose their memory and most of their mental function.

Over the course of the disease, the most common symptoms of Alzheimer's include the following:

• Having trouble remembering names or dates
• Repeating statements or asking the same questions
• Forgetting appointments or events
• Getting lost in familiar places
• Having trouble finding the right words
• Difficulty managing daily tasks at home or at work
• Trouble making decisions or judgments
• Difficulty planning multi-step activities
• Depression, apathy, or social withdrawal
• Mood swings and/or angry outbursts
• Irritability, agitation, or aggressiveness
• Changes in sleeping habits
• Loss of inhibitions
• Inability to perform daily tasks or basic hygiene
• Sundowning

These symptoms typically start out very mild but progress and become compounded over time. As the most common form of dementia, Alzheimer's disease follows a predictable pattern when it comes to the progression of symptoms. There are three stages of Alzheimer's:

• Early Stage (Mild Alzheimer's) – In the early stages of Alzheimer's, the patient may show few noticeable symptoms and may still be able to function independently. As the disease progresses, however, the patient may have trouble recalling names, performing daily tasks, and finding the right words for each situation.
• Middle Stage (Moderate Alzheimer's) – The middle stage of Alzheimer's can last for many years, during which time the patient may become increasingly more confused and agitated. The patient may become forgetful, moody, and confused, may need help with daily tasks and personal hygiene, and might start to develop personality or behavioral changes.
• Late Stage (Severe Alzheimer's) – In the final stage of Alzheimer's, the patient loses the ability to interact with their environment. In this stage, patients are typically unable to carry on a conversation or control their own bodily movement.

In most cases, patients with Alzheimer's disease live between 4 and 8 years after the diagnosis has been made, though some live as long as 20 years. While this disease most commonly affects adults over the age of 65, over 200,000 Americans under the age of 65 develop early-onset Alzheimer's each year.

Alzheimer's disease is not a normal consequence of aging but the result of physiological changes in the brain. Scientists are still struggling to fully understand these changes, but they have largely been attributed to the development of abnormal protein deposits that damage nerve cells. Though these changes are microscopic, they begin long before the first outward signs of Alzheimer's and they become compounded as the disease progresses.

The human brain has roughly 100 billion nerve cells, or neurons, in a giant network of connections. Within this network are a number of specialized nerve cells – each group is involved in certain functions, such as learning and memory. When the nerve cells responsible for memory and cognition sustain damage, it leads to the early symptoms of Alzheimer's.

Though they can only be identified through autopsy, a human brain affected by Alzheimer's shows abnormal deposits of proteins throughout the brain. Scientists believe that these deposits are somehow responsible for damaging and killing off nerve cells. Deposits of beta-amyloid protein that build up in the spaces between neurons are called plaques, and tangles are twisted tau fibers that accumulate inside the nerve cells themselves.

Scientists have yet to pinpoint the exact role plaques and tangles play in Alzheimer's disease, but it is clear they develop most heavily in areas of the brain responsible for memory before spreading to other regions. Because these deposits physically damage and eventually kill the affected nerve cells, the effects of Alzheimer's disease are irreversible.

Vascular Dementia

Once known as post-stroke dementia or multi-infarct dementia, vascular dementia is the second most common type after Alzheimer’s, accounting for about 10% of cases. This type of dementia is caused by a blockage or reduction in blood flow to the brain, which deprives it of oxygen and vital nutrients. Many medical experts believe this form of dementia is highly underdiagnosed, partially because its diagnosis can be challenging.

According to the American Heart Association (AHA), there are three criteria that suggest dementia symptoms are caused by vascular dementia:

1. Evidence of mild cognitive impairment can be confirmed by neurocognitive testing
2. Brain imaging tests show evidence of a recent stroke or brain blood vessel changes
3. There is no evidence that factors other than vascular damage are contributing to the decline

Symptoms of vascular dementia vary depending on the part of the brain affected by the blockage and the severity of the damage caused to the blood vessel. Cognitive impairment is very common with this form of dementia, though memory loss may or may not be a symptom. Because this is a vascular condition, early symptoms are not always noticeable except when they occur following a major stroke.

Common symptoms of post-stroke vascular dementia include the following:

• Mental confusion
• Disorientation
• Difficulty speaking
• Trouble understanding speech
• Loss of vision

These symptoms may occur all at once and may be accompanied by other major stroke symptoms, such as paralysis on one side of the face or body, difficulty walking, and a sudden headache.

Patients who suffer multiple small strokes may develop different symptoms, such as gradual changes in cognition, impaired judgement or poor planning, increased difficulty paying attention, impaired social function, uncontrolled laughing or crying, and trouble finding the right words.

Factors that may increase a patient’s risk for vascular dementia include smoking cigarettes, high blood pressure, high cholesterol, unhealthy diet, infrequent exercise, excess weight, obesity, and excessive alcohol consumption.

Dementia with Lewy Bodies (DLB)

The third most common type of dementia after Alzheimer’s and vascular dementia, dementia with Lewy bodies, or DLB, accounts for between 10% and 25% of cases. Like Alzheimer’s, this form of dementia is characterized by the accumulation of abnormal protein deposits in the brain. The difference is that Alzheimer’s plaques are comprised of beta-amyloid proteins while Lewy bodies are made up of alpha-synuclein, the same type of protein implicated in Parkinson’s disease. It is no surprise, then, that the symptoms of these two conditions sometimes overlap.

Symptoms of dementia with Lewy bodies are caused by aggregations of alpha-synuclein proteins forming in the cortex of the brain. Common symptoms of dementia with Lewy bodies include the following:

• Mental confusion
• Changes in alertness
• Hunched posture and rigid muscles
• Difficulty initiating movement
• Shuffling gait
• Balance problems
• Changes in thinking and reasoning
• Visual hallucinations or delusions
• Acting out violent dreams

Additionally, patients who have dementia with Lewy bodies may experience memory loss that is significant but not quite as prominent as with Alzheimer’s. The overlap between Parkinson’s and dementia with Lewy bodies can sometimes make diagnosis a challenge. Many Parkinson’s patients eventually develop problems with thinking and reasoning while patients having dementia with Lewy bodies often develop problems with movement and balance.

Diagnosis for dementia with Lewy bodies is tricky not only because the symptoms overlap with other conditions, but because a definitive diagnosis can only be made via postmortem autopsy. A clinical diagnosis for this condition is usually made by administering numerous tests to rule out other conditions and may be indicated when:

1. The first dementia symptoms to develop are consistent with DLB
2. Both symptoms of dementia and movement symptoms are present at the time of diagnosis
3. Dementia symptoms appear within a year after movement symptoms develop

In cases where movement symptoms develop first, the patient is more likely to be diagnosed with Parkinson’s disease than dementia. When the brain changes associated with DLB are present at the same time as Alzheimer’s symptoms or symptoms of vascular dementia, the patient may be diagnosed with mixed dementia.

Mixed Dementia

Dementia is caused by changes in the brain, though scientists are still working to understand why and how those changes occur. Because there remains more to be learned about the cognitive abnormalities implicated in different forms of dementia, an exact diagnosis is sometimes difficult to achieve. When dementia symptoms and brain abnormalities can be linked to more than one cause of dementia, the patient is likely to be diagnosed with mixed dementia.

New research suggests that mixed dementia is much more common than once thought. In fact, it is estimated that as many as half of older individuals who have dementia exhibit evidence of more than one cause. Furthermore, the risk for mixed dementia increases with age, peaking at the age of 85.

Symptoms of mixed dementia vary depending on the brain changes involved.

In cases where dementia is caused by Alzheimer’s combined with vascular dementia, the patient may exhibit memory loss, difficulty concentrating, trouble with speech and understanding, and mental confusion or disorientation. Alzheimer’s combined with dementia with Lewy bodies (DLB) may produce these symptoms in addition to changes in movement and balance. It is also possible for symptoms of all three types of dementia to be present.

Because symptoms are so widely varied, and the underlying cause of brain changes implicated in dementia so poorly understood, researchers are starting to realize that many patients currently diagnosed with a single type of dementia may actually have mixed dementia. This hypothesis is supported by the fact that autopsies show a higher prevalence of mixed dementia than previously realized.

Though diagnosis of mixed dementia can be a challenge, researchers believe that an increased understanding of the condition will lead to better understanding of specific types of dementia and the brain and vascular changes that accompany them. This may also lead to an improvement in diagnostic tools and preventive measures.