Pathophysiology of Alzheimer’s Disease

Introduction of Alzheimer’s Disease

Alzheimer’s Disease is named after Dr. Alois Alzheimer, in 1906 when he noticed changes in the brain tissue of a woman who had died of an unusual mental illness (Alzheimer’s Association, 2019). This mental illness was found to consist of amyloid plaques and tangles in the brain to be considered one of the things present in an individual’s brain that is a clear sign of the disease makeup. Alzheimer Disease is a brain disease that causes problems with memory, thinking and behavior most closely associated with dementia. 10% of individuals greater than 65 years of age has Alzheimer’s Disease and this increases 25% more with individuals greater than 85 years (Hubert, 375, 2018). The disease is commonly affecting the senior population. Intervention amongst Alzheimer patients is a great need for supervision and attention. Intervention amongst caregivers and registered nurses must be a top priority amongst the elderly population. “In Alzheimer’s disease, there is a progressive loss of intellectual function that eventually interferes with work, relationships, and personal hygiene” (Hubert, 375, 2018). Alzheimer’s disease affects 5.3 million individuals in the United States with the elderly population continuing to increase. With the continuing increase of Alzheimer Disease affecting the elderly population, intervention and education are greatly needed.

 Alzheimer’s disease is currently ranked as the sixth leading cause of death in the United States. Early onset of the disease consists of memory loss and forgetting recent conversations and it will develop into severe memory loss.

Etiology and Risk Factors

Alzheimer’s disease is a progressive deterioration of memory and cognitive functions in which it has a late onset (Annaert, 2015). This neurological disorder causes the death of brain cells causing memory loss and cognitive decline in which the first symptoms are mild and will gradually become more severe overtime. The disease affects individuals 65 years or older. The risk factors are age, genetics, sex, and head injury. Age is the greatest risk factor in Alzheimer’s disease. Family history and genetics also play a major role because it is connected to the genetic gene called apolipoprotein E gene when present increases the risk of Alzheimer’s disease (NIH, 2018). Females are more likely to develop Alzheimer’s Disease (AD) compared to males because they generally live longer. Individuals who’ve had severe head trauma are at greater risk in developing Alzheimer’s disease because they are at an increased risk of developing dementia and AD due to the decreasing number of neurons caused by head injuries (Li, 2017).

Pathophysiological Process

 Alzheimer’s Disease affects the 3 processes that keep neurons healthy: communication, metabolism, and repair (Chawla, 2019). Changes in AD include progressive cortical atrophy which leads to the neurofibrillary tangles in the neurons and senile plaques. Both neurofibrillary tangles and senile plaques are found in large numbers in the affect’s parts of the brain in which “the plaques disrupt neural conduction containing fragments from beta-amyloid precursor protein” (Hubert, 375, 2018). Amyloid plaques consist of abnormal proteins and fragments of nerve cells that are attached to other nerve cells. When a nerve cell dies the amyloid protein is embedded in the cell membrane and when it breaks off a fragment of the protein is still present, and it builds up in the brain. It’s the destruction and death of the nerve cells and the deposits of the protein on the membrane that causes memory failure, personality changes and carrying out activities of daily living.

Clinical Manifestations and Complications

One of the first signs of cognitive impairment is memory problems and the symptoms of Alzheimer’s vary from person to person. As we get older and our bodies change so does our brain. Memorization is an early symptom in which individual’s with Alzheimer’s disease have difficulty learning new material and increasingly severe symptoms start to appear. In the early years, gradual loss of memory becomes apparent, language skills continue to decline, managing activities of daily living become difficult, and in the late stage, the individual does not recognize his or her family members.

There are three stages of Alzheimer’s disease and they are mild, moderate and severe. Mild AD is memory loss and cognitive difficulties while moderate AD is when areas of the brain that control language and reasoning become damage and in severe AD the brain tissue shrink significantly affecting the communication between patient and family members.  Alzheimer’s disease can complicate treatment for other health conditions and when it professes to its last stages it affects physical functions and increase health problems such as fall, aspiration, and pneumonia.

Diagnostics

A key component of a diagnostic assessment is self-reporting about symptoms (Mayo Clinic, 2018). A diagnostic assessment that a doctor would perform is a physical/neurological exam, lab test, and brain imaging. During the physical/neurological exam, the doctor will assess the individual’s physical/neurological health by observing their coordination and ability to walk across the room. A blood test may help the physician rule out any potential cause of memory loss due to vitamin deficiency or a thyroid disorder. And brain imaging consists of an MRI (magnetic resonance imaging) and CT (computerized tomography) which may enable physicians to detect specific brain abnormalities.

References

• Alzheimer’s disease. (2018, December 08). Retrieved June 13, 2019, from https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/diagnosis-treatment/drc-20350453
• Alzheimer’s Disease Fact Sheet. (2019, May 22). Retrieved from https://www.nia.nih.gov/health/alzheimers-disease-fact-sheet#symptoms
• Chawla, J. (n.d.). Alzheimer Disease. Retrieved June 14, 2019, from https://emedicine.medscape.com/article/1134817-overview#a4.
• Hubert, R. J., & VanMeter, K. (2018). Goulds pathophysiology for the health professions(6th ed.). St. Louis, MO: Elsevier.
• Li, Y., Li, Y., Li, X., Zhang, S., Zhao, J., Zhu, X., & Tian, G. (2017). Head Injury as a Risk Factor for Dementia and Alzheimer’s Disease: A Systematic Review and Meta-Analysis of 32 Observational Studies. PloS one, 12(1), e0169650. doi:10.1371/journal.pone.0169650
• What is Alzheimer’s? (2019). Retrieved June 13, 2019, from https://www.alz.org/alzheimers-dementia/what-is-alzheimers
• Peric, A. & Annaert, W. Acta Neuropathol (2015) 129: 363. https://doi.org/10.1007/s00401-014-1379-7