Alzheimer’s Diagnosis and Risk Factors

Brain changes that lead to an Alzheimer’s diagnosis

New research in diagnosing Alzheimer’s disease has found that people with the disease show particular changes in the brain.  First, autopsies of Alzheimer’s patients’ show two kinds of lesions in the brain: plaques that clog the areas between the brain cells; and tangles that damage each brain cell from within.

With a build-up of plaques, communication between brain cells may be compromised.  The tangles appear to destroy the brain cells from the inside.  Some autopsies have revealed plaques and tangles in people who never developed symptoms. This suggests that changes in the brain may go on for years or decades before symptoms appear, and that some people’s positive attitudes or healthy lifestyles may help their brains compensate for the deficits and maintain normal functioning.

Another feature of Alzheimer’s is that the brain doesn’t produce enough of the chemical that enables communication between brain cells.  The changes in brain chemistry and structures slowly spread to many areas of the brain.  Parts of the brain slowly shrink and can no longer be in charge.  Recent developments in brain scanning technology have made it possible to see some of these changes to the brain as Alzheimer’s progresses.   Brain scans now have the potential to contribute to a diagnosis by showing such changes and ruling out other causes of dementia-like symptoms.

Risk factors that can contribute to an Alzheimer’s diagnosis

Even though we don’t yet know the cause of Alzheimer’s, a number of factors have been found over and over again in Alzheimer’s patients.  It may turn out that several things must occur together to cause the disease.  Experts suspect that some combination of the following could predispose a person to develop Alzheimer’s:

• Family history of the disease (especially a parent or a sibling)
• Heart-disease risk factors: high blood pressure, smoking, obesity, diabetes, high cholesterol
• Previous head injury
• Environmental toxins
• Advancing age
• Stress; high levels of anxiety; high levels of pessimism
• Genes: A gene variant called APOE E4 may be a risk factor, but only about thirty per cent of people with Alzheimer’s have this gene; other people with Alzheimer’s do not have the gene.  Early-onset Alzheimer’s is determined by a set of mutated genes.

The presence of any of these risk factors does not mean that you will get Alzheimer’s disease.  In fact, researchers can say only that these factors have been associated with many Alzheimer’s patients.  Take advancing age as an example: it’s listed as a risk factor only because Alzheimer’s disease usually strikes individuals after age 65.  Aging alone does not cause the disease.  Suppose we eventually discover that it’s caused by some combination of genes.  In that case, many people’s risk of getting the disease will remain low, no matter how old they get.  Until we know more about Alzheimer’s causes, we can’t be too sure about risk factors, so the best course of action is to eliminate any risk factors that you can control, as it could improve your chances of preventing Alzheimer’s or delaying its onset.

Are some people naturally protected from Alzheimer’s?

Scientists have reason to believe that certain gene variants play a role in protecting people against Alzheimer’s, especially a form of the APOE gene called APOE E2.  Another promising discovery is that some ethnic groups have a lower incidence of dementia than others.  One study found that among people with Cherokee ancestors, individuals with the highest percentage of Cherokee heritage had the lowest percentage of Alzheimer’s.  Scientists don’t yet know the exact way that these protective genetic factors work, and it seems likely that several genes influence the disease process.  Since research is ongoing, it may turn out that in groups with lower incidence of Alzheimer’s, lifestyle and environment are more influential than genes.  Even so, genetics holds some promise that we will one day understand this disease and find a cure.  

Diagnostic markers of Alzheimer’s

Diagnostic markers are clues in different body systems that a person has Alzheimer’s or is likely to get Alzheimer’s. Research results in this area may help physicians to diagnose and treat Alzheimer’s earlier. Researchers are learning about markers in three parts of the body – spinal fluid, the brain, and the genes.

Body systems that offer diagnostic markers of Alzheimer’s
Spinal Fluid	The Brain	The Genes
A high level of the protein ADDL in the spinal fluid of Alzheimer’s patients reflects higher-than-normal concentrations of ADDL in their brains.	Brain scans show anomalies characteristic of Alzheimer’s. EEGs display a difference in brain functioning.	Genetic testing can show whether a person has genes that may predispose them toward developing Alzheimer’s, or genes that might protect against the disease.

Both the brain markers and the genetic markers are signs that the disease may be present, but neither determines that the disease is present.   As scientists learn more about Alzheimer’s causes, brain and genetic markers may become a more important part of diagnosis than they are today.

Testing and screening to diagnose Alzheimer’s disease

Professionals now believe they can diagnose Alzheimer’s with a great deal of certainty by applying a number of tests and measures, even very early in the course of the disease.  A hands-on physical exam and in-depth interviewing of patient and family are part of the process, along with various medical and psychological tests.  When other causes of symptoms have been ruled out, the diagnosis is “probable” or “possible” Alzheimer’s, even though the certainty is in the ninety percent range.

Doctors can take a number of steps to diagnose Alzheimer’s:

1. Neuropsychological tests: Performance on a battery of tests is measured against contemporaries with a similar educational level and in a similar cultural setting. A wide range of functions is evaluated including: memory, attention, communication, orientation in time and space, language and math skills, mood and emotions, and problem solving.
2. Interviews with the patient and family members: Interviews delve into family health history, risk factors that are present, and cognitive or behavior changes that have led to seeking medical help
3. A physical examination: A thorough exam, including Blood, urine, and spinal fluid lab tests
4. Assessment of difficulties in the activities of daily living: This includes eating, dressing, and personal hygiene.
5. An examination of the nervous system: These procedures test sensation and balance.
6. An MRI or CT scan: A head scan can open up the possibility of Alzheimer’s, or eliminate the possibility of a stroke, brain hemorrhage, or brain tumor.
7. A medical history: Including general health, nutrition, prescription and nonprescription drugs taken, and current and past mental and physical health problems.

Requirements for a Diagnosis of Alzheimer’s disease

Many of the following items must be present before the symptoms would be classified as Alzheimer’s disease:

• Memory impairment
• At least one additional cognitive impairment from among the following domains:
  • language (understanding written or spoken words; speaking)
  • perception (despite intact sensory functioning)
  • voluntary motor control (despite intact motor functioning)
  • executive functioning (self-regulation)
• Both the memory impairment and the other cognitive deficits are progressively worsening
• The memory and cognitive impairments must cause difficulty in social or occupational settings
• Onset is gradual and progressively worsening
• Onset is after age sixty-five
• The cognitive impairments do not occur only during delirium
• The absence of another disorder: brain disease or brain injury, systemic disease, substance abuse, or other factors that could explain the dementia

Notice that the diagnosis requires the ruling-out of other causes for the dementia. This is difficult, and Alzheimer’s is sometimes mistakenly diagnosed as the cause of the dementia. If the diagnosis is not certain, a doctor will ask for a re-evaluation in six months to check for a progression of symptoms.

The importance of an early Alzheimer’s diagnosis

Once you recognize the signs and symptoms of Alzheimer’s, the sooner you get a diagnosis the better. You may find that the symptoms are from another disease or condition that is curable. For instance, if the dementia is caused by a brain tumor or a vitamin deficiency, you can seek out the proper treatment sooner.

If the diagnosis is Alzheimer’s, you can involve your loved ones in long-range planning and decision-making about their own care while you are still lucid, and arrange caregiving for yourself without undue pressure.

Early diagnosis leads to early treatment, which is important: the drugs and lifestyle changes that slow down or halt Alzheimer’s disease work better the sooner you begin them. You can also get an early start in treating psychiatric and other manageable symptoms that accompany Alzheimer’s disease.

What to do after receiving an Alzheimer’s diagnosis

If you have been diagnosed with Alzheimer’s disease, you may react with surprise, denial, depression, anger, loss of self-esteem, or fear.  It’s important to face these feelings and move forward with planning for your future. You will be more lucid in the first stages of the disease, so take some important steps right away. Educate yourself and your family about Alzheimer’s; learn about the disease and what can be done to slow down its progress.

See a doctor regularly

Come to your doctors appointments with a list of questions and concerns. Report any changes that you have noticed – it’s a good idea to keep a diary where you can track your symptoms, and share this with your physician.
Make sure that your doctor monitors your blood pressure, cholesterol, and weight. A healthy heart gives you a healthy brain.
You can ask your doctor if there are any medications that can lessen your symptoms, or discuss enrolling in clinical trials. Perhaps take along an advocate to take notes and to ask additional questions.

Prepare your home

Make your living space a safe and comfortable environment. Now is the time to recognize that you are likely to have more and more problems coping with everyday activities and that your surroundings can be set up to help compensate for the deficits that develop. Establish routines that will help you to stay well-oriented and functioning independently.

Continue to see friends and family, and find additional support

Help your family members to express their feelings about the diagnosis and to learn as much as they can about the progression of the disease.  Take time to enjoy family gatherings, social events and other activities as in the past, without constantly dwelling on the diagnosis. If you’re having a hard time talking with friends and family about Alzheimer’s, you may want to join a support group. People will want to help you with your feelings about the diagnosis, so don’t be afraid to ask.

Get started on long-range planning with your loved ones

Discuss who will be caregivers.  Family caregivers can become educated about the disease and set up a support and respite system for themselves with community services and other family caregivers. Consider the various long-term-care options, such as in-home care or care in an assisted living facility.

Plan financially for the years of caregiving by examining health insurance coverage, long-term-care insurance coverage, and assets. Prepare a will and designate who manages the finances as you become less able to do so.

Advice for loved ones and caregivers

If your loved one has just been diagnosed with Alzheimer’s disease, and you are one of the designated caregivers, you can take some steps to make the years ahead a little easier,

Related links on Alzheimer’s diagnosis and risk factors

Alzheimer’s Diagnosis

Alzheimer’s Diagnosis  A definitive diagnosis of Alzheimer’s is possible only by examining brain tissue after death. ... Alzheimer’s Diagnosis Truths Alzheimer’s Diagnosis Tests ... (ALZinfo.org)

Diagnosing Alzheimer’s: An interview with a Mayo Clinic specialist. Many doctors still believe that an early diagnosis of Alzheimer’s would overwhelm both families and physicians. It takes a lot of time and effort to manage .....(Mayo clinic )

Alzheimer’s Causes and Risk Factors 

Alzheimer’s Disease and Risk Factors – Comprehensive information on individual risk factors and reducing these risks. (Alzheimer’s Society of Canada)

Alzheimer’s Research on Causes and Risk Factors – Information on recent advancements in Alzheimer’s research. (Fisher Center for Alzheimer’s Research)

After an Alzheimer’s Diagnosis

Persons with Memory Loss – A set of articles written for the Alzheimer’s patient. Topics are managing your life, taking care of yourself, coping with the diagnosis, and planning for your future. (Alzheimer’s Association)

After the diagnosis – Offers tips on directions to take after receiving a diagnosis of Alzheimer’s. Sections include getting support, financial planning, healthcare directives, considering treatments, driving, and staying independent. (Alzheimer’s Society, UK)

Doug Russell, L.C.S.W., Suzanne Barston , and Monika White, Ph.D., contributed to this article. Last modified on: 12/20/07.