Alzheimer's Disease

Welcome to the Affordable Drugs Alzheimer's disease information page. Alzheimer's disease is sometimes referred to as Alzheimer's dementia. The information about Alzheimer's disease contained on this page is intended for Alzheimer's patients and their families as well as Alzheimer's caregivers. Here you can learn about Alzheimer's symptoms, Alzheimer's stages, Alzheimer's treatments and more. You can also find the best prices available on Alzheimer's medications. The information on this page is not intended to replace the professional advice of your physician. For the latest Alzheimer's articles visit our health news section.

What Is What is Alzheimer's Disease?

Alzheimer's disease is an incurable, degenerative type of dementia which generally affects people over the age of 65, although an early-onset form may strike younger men and women. The disease was diagnosed in 1906 by German physician Alois Alzheimer.

The disease causes progressive loss of memory and cognitive function as a result of neural and other tissue atrophy of the brain, eventually resulting in death caused by related factors.

What is Alzheimer's disease caused by?

The causes of Alzheimer's are not known, but there are several mechanisms which are suspected to be associated with the development of the disease.

The underlying causes and mechanisms of Alzheimer's disease are not understood. Currently, there are three theories addressing possible causes, although none presents a complete explanation.

In the earliest posited initial hypothesis of the disease, called the cholinergic hypothesis, researchers supposed the development ofAlzheimer's disease is related to a decrease in the body's natural production of a neurotransmitter called acetylcholine. Many drug therapies have been developed based on this hypothesis, but due to their relative inefficacy in halting the disease progression, the hypothesis is no longer widely supported. Researchers who adhere to this hypothesis also believe other cholinergic factors may cause general inflammation of the neural system and components.

In the late 2oth century, researchers developed a competing hypothesis which focused on the protein called amyloid-�. Researchers believe built-up deposits of this protein have a genetic influence that triggers the onset of the disease. In early trials, a vaccine developed to clear amyloid buildup did not have an effect on the development of dementia. Further research has indicated that related amyloid-� factors, and not necessarily amyloid-� specifically, may cause degenerative brain disease by binding to gene receptors on neurons.

A third hypothesis regarding the genesis ofAlzheimer's disease is known as the tau hypothesis, named for the tau protein. In this theory, the protein begins to irregularly bind with other tau protein strands, forming tangles that can interfere with neural transmission and eventually cause areas of the brain to malfunction and atrophy.

What isAlzheimer's disease characterized by?

Alzheimer's disease generally is recognized to comprise several distinct stages. In the first stage, called pre-dementia, early symptoms of memory loss and mild cognitive insufficiency may occur nearly a decade before definitive symptoms ofAlzheimer's. The most common symptom is short-term memory loss, and there may also be impairment in abstract thinking, attentiveness, and planning functions.

In early dementia, the next stage of Alzheimer's disease, cognitive function continues to decline and a definitive diagnosis can be made. Some individual may experience language deficiencies, notably within the context of vocabulary and fluency. Short-term memory loss also becomes more acute and the patient may also begin to lose certain fine motor skills, making movement and daily tasks difficult to complete smoothly.

Early dementia eventually resolves into moderate dementia, where patients lose significant fine motor skills use and are usually unable to complete the tasks of day-to-day living. Language and memory continue to decline, and patients may fail to recognize family members. Incontinence, delusion, and certain behavioral problems, such as wandering and emotional outbursts are common. Many of these symptoms worsen as the evening progresses.
In advanced dementia, the final stage ofAlzheimer's disease, speech declines significantly and may be lost entirely. Aggression may still be present, but is generally much less prevalent as patients become easily exhausted and less responsive to their environment. Motor skills decline rapidly and patients may become bedridden. Help is needed with feeding and other basic activities. Eventually, death occurs as a result of external factors, such as pneumonia or other illness.
 

Stages of Alzheimer's Disease

Here we will detail the progressive stages of Alzheimer's Disease. We will view these in terms of seven developmental stages, broken into three categories: mild, moderate, and severe.

Mild Stages: The early stages of Alzheimer's Disease are the most manageable. For the first two-to-four years, an Alzheimer's patient might start to show signs of memory loss.

1. Initially, there will be no noticeable symptoms. Memory will not have deteriorated to the point of impairment.

2. As the disease progresses, mild loss of memory will begin. Initially, this will be more noticeable to the patient. This will still be difficult to distinguish from the ordinary affects of aging on the cognitive process.

3. Towards the end of the early stages of Alzheimer's Disease, symptoms might become noticeable to family and medical professionals. For example, you might notice the patient placing personal effects such as keys or eyeglasses in unusual locations and losing them on a regular basis. They might repeat the same questions. Using objects with their hands might become more complicated. They will need help remembering their daily responsibilities. This is one of the more manageable of the defined Alzheimer's stages, though you must be prepared for some mood swings and depression.

Moderate Stages: These progressing stages of Alzheimer's Disease can last up to a decade. This is where the onset of the disease becomes clear to friends and family.

4. Major memory problems start to affect every aspect of life. This will manifest itself initially in the form of unusual problems with complex memory or cognitive processes. Organizing a plan which requires the management of several details or challenging math will slip out of reach.

5. As the disease further encroaches upon the useful faculties of the patient, more ordinary tasks will become too challenging. Current details about the sufferer's life, such as telephone number, may be hard to recall. Simpler math will become challenging. The patient will still have the cognitive ability necessary to carry out many of their daily tasks.

6. As the cognitive reasoning begins to fail, simpler tasks will become challenging. Communication becomes very difficult. Time distortion becomes a major problem. The patient may appear to be lost in places they typically frequent. Motor function will deteriorate, and this will restrict ease of movement. Most patients will begin suffering from behavioral problems as a result of coping with these new complications. This part of the Alzheimer's stages will require assistance for the sufferer.

Severe Stage: The final of the stages of Alzheimer's Disease is the most difficult. This step is categorized as severe and will involve a deterioration of all motor skills leading eventually to death.

7. Motor skills will fail to the point of incapacitation. This will make it difficult for the patient to even swallow food. Incontinence will manifest as a problem. Memory will fail to the point of delirium. Mood and behavior will become very erratic, and the power of speech will slip away. In the final of Alzheimer's stages, it is imperative that a patient have constant care from someone who understands what they need.
 

Causes of Alzheimer's Disease

Alzheimer's Disease is an irreversible disorder that causes progressive failure of brain cells. It affects an estimated 2-5% of people over the age of 65, and approximately 20% of people age 85 and older. Causes of Alzheimer's Disease are not fully understood by medical professionals. However, there are primary characteristics of the disease, genetic components, and risk factors that can impact upon the likelihood of developing Alzheimer's.

Research has shown that some causes of Alzheimer's Disease may be due to the existence of excessive protein deposits in the brain. These proteins, known as amyloid plaques and neurofibrillary tangles, manifest themselves most often in the hippocampus and the cortex regions of the brain. Amyloid plaques tend to gather between between neurons. Although the human body normally produces amyloids or protein fragments, these fragments become insoluble and accumulate in Alzheimer's patients.

Neurofibrillary tangles are found in brain cells of Alzheimer's patients as insoluble, twisted fibers. A protein known as "tau" comprises the majority of the tangles. Elements of tau proteins play a role in the composition of microtubules, which, in healthy people, carry nutrients among the components of brain cells. In patients with Alzheimer's Disease, these microtubules collapse because of abnormalities in the tau proteins.

There is a genetic element in Alzheimer's causes. Scientists have identified several genes that are definitely associated with Alzheimer's, and are constantly working to discover more. An inherited, early-onset version of the disorder has been caused by at least two types of genetic mutations. Another gene, known as apolipoprotein E-e4, or APOE-e4, has been identified as a main Alzheimer's risk gene. Copies of the APOE gene are inherited by all people from their parents. If a person inherits one copy of the APOE-e4 gene, he or she has a greater chance of developing Alzheimer's. If two copies of APOE-e4 are inherited, the risk of Alzheimer's increases, but there is still no certainty of developing the disorder.

In rare cases, causes of Alzheimer's are due to the existence of a deterministic gene. This gene, found in only several hundred extended families throughout the world, has the capability of affecting multiple generations.

In addition to genetic components, there are several risk factors that contribute to the development of Alzheimer's. Advanced age is the key risk factor. The likelihood of being diagnosed with the disorder nearly doubles every five years after a person reaches age 65. Family history also plays a role. If a member of an immediate family (parent or sibling) has been diagnosed with Alzheimer's, other members of that family are two to three times more likely to develop the disease. Lifestyle factors may also influence the onset of the disorder. People who have experienced severe head injuries may be at increased risk, as are those who have elevated cholesterol levels and high blood pressure. Diets which are deficient in essential vitamins may contribute to the development of Alzheimer's. There is also a loose correlation between lack of exercise, both physical and mental, and the onset of Alzheimer's. 

Alzheimer's Diagnosis

Overview

Diagnosing Alzheimer's is a complex, multiple-approach process due to the very nature of this disease. Unlike some illnesses in which one or two laboratory tests can be employed to establish their existence, Alzheimer's diagnosis will require a series of diagnostic procedures that will simply rule out all other possible causes of the observed symptoms. When no other physiological reason is discovered to explain the symptoms of memory loss, radical mood changes, and disorientation, then the physician will suspect the presence of Alzheimer's disease. Even then, only an autopsy of the brain can provide irrefutable proof of Alzheimer's. This is why Alzheimer's diagnosis only has 90 percent accuracy.

Nevertheless, diagnosing Alzheimer's at its earliest stages is still regarded as vital. Early Alzheimer's diagnosis can help the patient slow down the progress of the disease because medications are most effective during the early stages. Alzheimer's diagnosis will also give patients and their families enough time to make future plans and to cope with the worsening symptoms of this disease.

Diagnostic Procedures

Medical History - In this procedure, the doctor wants to find out about previous health problems and the medications taken to address these problems. Some infections such as meningitis may produce symptoms similar to that of Alzheimer's. Some medications will have side effects and/or drug interactions that may produce Alzheimer-like symptoms. This Alzheimer's diagnosis will also involve a questionnaire or personal interview with close family member to discover any abuse of drugs and other similar situations.

Physical Examination - In this procedure, the patient's senses, blood pressure, and other physiological conditions are evaluated. Since diagnosing Alzheimer's is eliminating all other possible causes of symptoms, the physical examination will determine if the patient is not suffering from impaired sensations due to vitamin deficiencies, malnutrition, organ failure, and even chronic sleep deprivation.

Laboratory Tests - There are no special laboratory tests for diagnosing Alzheimer's. But standard laboratory tests such as blood tests, urine tests, and depression screening can be employed to verify the presence of other medical conditions that may explain the observed symptoms. Diseases such as Parkinson's, Huntington's, and epilepsy will have symptoms that are similar to that of Alzheimer's.

Neuro-psychological Testing - In this Alzheimer's diagnosis, the physician will determine if there are no other psychological or neurological problems that could have caused the symptoms. This diagnostic test evaluates the patient's visual discrimination, hand-and-eye motor coordination, abstract thinking, and problem solving abilities. The physician wanted to find out if the patient is suffering from illnesses such as vascular dementia, psychosis, and emotional trauma.

Brain imaging scan - This Alzheimer's diagnosis may utilize imaging techniques such as CT (Computerized Tomography), MRI (Magnetic Resonance Imaging) or PET (Positron Emission Tomography). There are two major purposes for the brain scan. First, the physician would like to rule out the presence of a brain tumor. And second, the physician wanted to observe brain activity. Low brain activity, such as shown in numerous blue and black areas in a PET brain image, indicate the destruction of brain cells.

Alzheimer's Medications

There are several Alzheimer's medications which are currently approved by the U.S. Food and Drug Administration.  None of these medications can actually cure or stop the disease; they can only slow down the symptoms.  The drugs currently approved (at the time of writing) are: Aricept (donepezil), Razadyne (galantamine), Exelon (rivastigmine), Cognex (tacrine), and Namenda (memantine).

Medications approved for the treatment of mild to moderate Alzheimer's disease includes Aricept, Razadyne, Exelon, and Cognex.

Aricept's active ingredient is donepezil, which is an acetylcholinesterase inhibitor.  Acetylcholinesterase is an enzyme which breaks down acetylcholine, a neurotransmitter thought to play a role in memory and other cognitive functions. Aricept works by inhibiting the enzyme acetylcholinesterase, so that the neurotransmitter acetylcholine is not broken down and remains available to the nerve cells of the brain for longer periods of time. While scientists are not completely certain just how and why acetylcholinesterase inhibitors work, they have found through multiple studies that it has proven to decrease the effects of Alzheimer's.

Razadyne, also known as the galantamine, is a chemical alkaloid that originated in the bulbs of certain flowers. Galantamine, like donepezil, is also a cholinesterase inhibitor, and also increases the amount of acetylcholine in patients' brains. Studies have also shown galantamine to have some effect in boosting acetylcholine release from nicotinic cholinergic receptors.

Exelon also goes under the name of rivastigmine. This chemical is used not only with patients suffering from Alzheimer's disease but also Parkinson's disease. Rivastigmine, unlike the drugs mentioned above, is both an acetylcholinesterase inhibitor and a butyrylcholinesterase inhibitor. However, rivastigmine works in a similar manner as the other cholinesterase inhibitors. It has proved to be useful in improving behavioral, cognitive, and functional difficulties caused by both Alzheimer's and Parkinson's disease.

Cognex is the least commonly prescribed drug for patients suffering from mild to moderate Alzheimer's disease. It was the first of the cholinesterase inhibitors to be developed for the treatment of Alzheimer's disease. Also known as tacrine, Cognex works in the same way as all the other acetylcholinesterase inhibitors.

There is only one drug approved for moderate to severe cases of Alzheimer's disease.  That drug is memantine, also known by the trade name Namenda.

Memantine is an N-methyl D-aspartate (NMDA) receptor antagonist.  This means it blocks NMDA receptors. It is hypothesized that overstimulation of NMDA receptors by glutamate (a neurotransmitter) may play a role in Alzheimer's disease.  The reason scientist think this is because glutamate plays an important role in the neural pathways associated with learning and memory.  Abnormal levels of glutamate is thought to cause to much excitement of nerve cells leading to neuronal cell dysfunction and the eventual cell death. Namenda is thought to selectively block the harmful effects contributed to abnormal transmission of glutamate, while still allowing for the physiological transmission associated with normal cell functioning.

Though memantine has not been proven to stop or slow the progression of Alzheimer's disease itself, many symptoms of the disease can be slowed. For example, patients in later stages of Alzheimer's who are on Namenda may be able to retain the ability to use the restroom by themselves for a longer period of time. However, some doctors may not recommend memantine; they may believe that the exorbitant cost of the drug predominates over the benefits they drug may cause in patients.

Memantine is often used in conjunction with Aricept (donepezil) for treatment of mild to moderate cases of Alzheimer's. Because memantine works by a different mechanism of action than donepezil does, they can be combined safely. When used together in cases of moderate to severe Alzheimer's, they are much more effective and show greater gains in behavioral, cognitive, and functional abilities.