Diseases & Conditions

 

Alzheimer's disease

Diseases & Conditions

Alzheimer's disease

What is Alzheimer’s disease?

Alzheimer’s disease is a non-reversible, progressive brain disorder that develops over a period of years destroying memory and other important mental functions. In this disease, the brain cells degenerate and die leading to changes in behavior and personality and a decline in cognitive abilities such as decision-making and language skills. Alzheimer’s disease ultimately leads to a severe loss of mental function and the inability to carry out the simplest tasks. It is the most common cause of dementia among people age 65 and older. 1

In the Kingdom of Saudi Arabia, there are no official statistics on the spread of Alzheimer's disease, but experts estimate that there are at least 50,000 patients living with this disease in the country. The Saudi Alzheimer's Disease Association indicates that the chances of getting the disease double every 5 years among individuals aging more than 65 years, while that half of those aging over 85 years were found affected by the disease.2

What causes Alzheimer's disease?

The causes of Alzheimer's are not yet fully understood, although people with Alzheimer's disease have been found to have abnormal amounts of protein (amyloid plaques) and fibers (neurofibrillary tangles) in the brain:3

  • Amyloid plaques are fragments of a protein called beta-amyloid peptide that may damage and destroy brain cells in several ways.
  • Neurofibrillary tangles are abnormal collections of a protein called tau. Normal tau is required for healthy neurons. However, in Alzheimer’s disease, tau protein twists into abnormal tangles inside neurons. As a result, neurons fail to function normally and eventually die.

Amyloid plaques and tangles will lead to a loss of connections between neurons, which will be responsible for memory and learning decline. Neurons cannot survive when they lose their connections to other neurons. This loss of connection is strongly implicated in the shrinkage of the affected brain regions. People in the final stages of the disease have a widespread damage with significant shrinkage of their brain tissue.

Who is at risk for getting Alzheimer's disease?

Although it is still unknown what triggers Alzheimer's disease, several factors are known to increase the risk of developing the condition. These risk factors are of two types: unavoidable risk factors and modifiable factors (someone can reduce his risk of getting Alzheimer’s disease by keeping these conditions under control).4

  • Unavoidable or sporadic risk factors4
    • Age: The greatest risk factor of Alzheimer’s disease is advanced age. A greater proportion of people over 85 years have it than those over 65 years of age.
    • Family history: Individuals who have a parent, brother or sister with Alzheimer’s are more likely to develop the disease. This is the second biggest risk factor after age.
    • Genes: Having a certain gene (the apolipoprotein E or APOE gene) puts a person, depending on their specific genetics, at three to eight times more risk than a person without the gene. Numerous other genes have been found to be associated with Alzheimer's disease.
  • Modifiable risk factors4
    • Factors that increase blood vessel (vascular) risk - including diabetes, high cholesterol and high blood pressure: These also increase the risk of stroke, which itself can lead to another type of dementia.
    • Mental stimulation: Studies suggest that remaining mentally and socially active may support brain health and possibly reduce the risk of Alzheimer’s disease.
    • Healthy diet and regular exercise may be a beneficial strategy to reduce your risk of developing Alzheimer's disease.

What are the signs and symptoms of Alzheimer’s disease?

Alzheimer’s disease affects people in different ways. The most common initial symptom is a gradually decreasing ability to remember new information. This occurs because the first neurons to malfunction and die are usually neurons in brain regions involved in forming new memories.

The following are common symptoms of Alzheimer’s disease:5

  • Memory loss that disrupts daily life especially forgetting recently learned information
  • Problems in planning or solving problems such as working with numbers and difficulty concentrating
  • Difficulty completing familiar tasks at home, at work or at leisure like driving to a familiar location
  • Losing track of time and place
  • Difficulty in reading, judging distance and determining color or contrast
  • Problems with words in speaking or writing and struggling to follow a conversation or repeating themselves
  • Misplacing things and losing the ability to retrace steps
  • Decreased or poor judgment
  • Withdrawal from work or social activities
  • Changes in mood and personality, including apathy and depression

A person in the earlier stages of Alzheimer's will often have changes in their mood. They may become anxious, irritable or depressed. Many people become withdrawn and lose interest in activities and hobbies.

How is Alzheimer’s disease diagnosed?

Alzheimer disease is usually diagnosed on physical and neurological exams, and checking for signs of intellectual impairment through standard tests of mental function. For a diagnosis of Alzheimer’s disease, new criteria were published in 2011.6 In this guideline, the physician obtains a medical and family history, including psychiatric history and history of cognitive and behavioral changes. The deficits should include impairment in learning and recall of recently learned information, deficits in word-findings and visuospatial cognition and impaired reasoning, judgment, and problem solving.

In addition, the physician conducts cognitive tests and physical and neurologic examinations. Moreover, he may request that the individual undergo computed tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET), to rule out other possible causes for symptoms.

What treatment and management options are available for Alzheimer's disease patients?

There is currently no cure for Alzheimer’s disease, and drug therapy is still in its early stages. Approved medications help control the symptoms of Alzheimer’s disease but do not slow down the progression or reverse the course of the disease itself. At present, only drugs that target neurotransmitter systems in the brain are used for treating Alzheimer’s disease.7

Doctors can offer pharmacological treatment and non-pharmacological interventions:8

  • Pharmacological treatments

As discussed above, there is currently no medical treatment to stop or reverse the progression of Alzheimer’s disease. However, six drugs have been approved by the U.S. Food and Drug Administration that temporarily improve symptoms of Alzheimer’s disease by increasing the amount of chemicals called neurotransmitters in the brain. These medications have been shown to improve quality of life through all stages of the disease for individuals with Alzheimer’s disease.8

  • Non-pharmacological interventions

The primary goals of non-pharmacological interventions are to maximize the patient’s ability to function in daily life, maintain quality of life, slow the progression of symptoms, and treat depression or disruptive behaviors. Such interventions comprise physical therapy and reminiscence therapy (therapy in which photos and other familiar items may be used to help the patient remembers). It is important to note that this kind of therapy does not alter the course of the disease but it can help the brain compensate for impairments and enhance the patient’s quality of life.

References:

  1. Alzheimer’s, Association. "2015 Alzheimer's disease facts and figures." Alzheimer's & dementia: the journal of the Alzheimer's Association 11.3 (2015): 332.
  2. "Dementia: A Journey of Caring." Ministry of Health Portal: Kingdom of Saudi Arabia. Web. 16 Nov. 2015. <http://www.moh.gov.sa/en/HealthAwareness/healthDay/2013/Pages/HealthDay-019.aspx>.
  3. Serrano-Pozo, Alberto, et al. "Neuropathological alterations in Alzheimer disease." Cold Spring Harbor perspectives in medicine 1.1 (2011): a006189.
  4. Beier, M. T. "Alzheimer’s disease: Epidemiology and risk factors." University of Tennessee Advanced Studies in Pharmacy, ASIP 2 (2005).
  5. Shivanand, Pandey. "A review on Alzheimer’s disease: its cause, symptoms, and treatments at worldwide.” (2010).
  6. McKhann, Guy M., et al. "The diagnosis of dementia due to Alzheimer’s disease: Recommendations from the National Institute on Aging-Alzheimer’s Association workgroups on diagnostic guidelines for Alzheimer's disease." Alzheimer's & Dementia 7.3 (2011): 263-269.
  7. Korolev, Igor O. "Alzheimer’s Disease: A Clinical and Basic Science Review." Medical Student Research Journal 4 (2014): 24-33.
  8. Zec, Ronald F., and Nicole R. Burkett. "Non-pharmacological and pharmacological treatment of the cognitive and behavioral symptoms of Alzheimer disease." NeuroRehabilitation 23.5 (2008): 425.