Alzheimer’s disease
Alzheimer’s disease is the most common type of dementia. Dementia is a term used to describe a variety of conditions and diseases that occur when the nerve cells in the brain degenerate or function abnormally. The degeneration of neurons results into changes in memory, behavior and cognitive functions. Alzheimer’s disease causes changes that eventually impair the ability of an individual to carry out bodily functions like walking and swallowing. The disease may ultimately lead to death. Early symptoms of the disease include gradual drop in the ability to recall new information. This is due to the disruptions of brain cells in the region of the brain involved with the formation of new memories. The spread of the damage leads to other problems such as: confusion with place and time; inability to understand visual images; problems with speaking or writing words and deterioration of cognitive abilities.
The number of people living with Alzheimer’s disease increases with an increase in the proportion of the U.S. population over 65 years of age. The number of Americans living with Alzheimer’s disease was estimated at 5,400,000 people in 2012. These included 5,200,000 people aged 65 years and older and 200,000 people under the age of 65. From the estimate it was determined that 1 in every 8 people aged 65 and older has Alzheimer’s disease. Close to half of the people of age 85 years and above have Alzheimer’s disease. Out of the total number of people with Alzheimer’s disease, 4% are below 65 years old, 6% are between 65-74 years old, 44% are between 75-84 years old, and 46% are 85 years old and above. The number of women with Alzheimer’s disease is more than that of men. About two thirds of those with the disease are women. 3,400,000 of the 5,400,000 Americans with Alzheimer’s are women, while 1,800,000 are men. 16% of women of age 71 years and above have Alzheimer’s disease, while only 11% of the men have the disease. The higher number of women living with Alzheimer’s disease compared to men has been linked to the fact that women live longer than men. The less educated people have a higher probability of developing Alzheimer’s disease than the more educated. Researchers explain that more years spent on education provides a “cognitive reserve”, which allows for better compensation for changes in the brain that could cause Alzheimer’s disease. Another explanation could be that low level of education is common with people of the lower socioeconomic class. These people have less access to quality medical care. Most of the people living with Alzheimer’s disease in the U.S are non-Hispanic whites, however, African-Americans and Hispanics are more likely than whites to develop Alzheimer disease. These differences are accounted for by health conditions that increase the risk for Alzheimer’s disease, and are common in African-American and Hispanic communities. The conditions include high blood pressure, and diabetes. The incidence rate of Alzheimer’s disease increases with age, from about 54 cases in every 1000 people aged between 65-74 years, to 170 cases in every 1000 people aged between 75-84 years, to 231 cases in every 1000 people over 85 years old. At this rate, it is projected that by 2050, the annual incidence of Alzheimer’s disease will be double the current rate. Between the years 2000-2025, the number of people with Alzheimer’s disease is expected to increase by double digit percentage in some regions in the country, which experience an increase in the proportion of the population aged 65 years and above. An increase of 50% and above is expected from the Southern and Western regions of the country. Currently, the Northeastern region has the highest number of those with Alzheimer’s disease.
Several genetic mutations increase the production of amyloid-beta and are linked to early onset of Alzheimer’s disease. Amyloid-beta is the major constituent of extracellular plaques, and is considered as one of the two indicators of Alzheimer’s disease. It is formed by cutting of larger amyloid precursor proteins into smaller fragments, oligomers, which have been shown to be toxic in cultured neurons. Sporadic form of Alzheimer’s disease has no genetic cause known. However, researcher’s show that ApoE4 gene increases the risk of developing Alzheimer’s by a factor of 2.83. The risk factor is increased to 11.42 with the considerations of lifestyle factors. These include alcohol drinking, smoking, physical inactivity, and increased intake of saturated fats. In other words, lifestyle factors may greatly increase the risk of Alzheimer’s in genetically susceptible people. Those in the lower socioeconomic class have increased risk for Alzheimer’s because they lack access to quality medical care. Environmental toxic chemicals also increase the risk to Alzheimer’s disease. Exposure to lead may harm the brain. Study shows that lead toxicity affects cognitive function, visual-motor function, verbal memory and learning. Lead is able to cross the blood brain barrier and disrupt the metabolism and release of neurotransmitters, and cause aggregation of amyloid-beta. Aluminum salts used to clarify water, make desserts and baked goods rise. Consumption of high varieties of aluminum from these foods may facilitate memory loss. High levels of aluminum are also associated with plague and tangle formation. A recent study showed that exposure of human neural cells to high concentration of aluminum triggered gene expression that increased inflammation and necrosis. Reports suggest that air pollution may facilitate brain inflammation and Alzheimer’s disease. The toxic gases are ozone, nitrogen, sulfur oxides, and carbon monoxide. Metals like lead and manganese also constitute the toxic complex. Evidence links air pollution to neurodegenerative disease. Brain tissue pathology of polluted city residents showed inflammation and Alzheimer’s type brain tissue.
During brain development, the decline in primitive infant reflexes is due to myelination of neurons in the brain. Myelination pattern is also linked to the progression of cognitive function losses in Alzheimer’s disease. Cognitive decline is linked to increased myelin degeneration. This may explain the reason behind memory loss in Alzheimer’s disease, and these changes increase as one grows older. The social needs of patients with Alzheimer’s disease are not well understood. With the progression of the disease, the patient requires love, acceptance, and socialization opportunities in order to maintain dignity.
The treatment of a patient diagnosed with Alzheimer’s disease involves the development of a plan. The patient and the family are involved, and it includes psychiatric, neurological, and medical evaluations to determine the cause and nature of the disease. The cultural background of the patient is also involved to determine any factor, genetic, socioeconomic or environmental, which could influence the occurrence of the disease. If the condition of the patient is mild at diagnosis, acetylcholinesterase inhibitor is administered. Reevaluation of the patient is done after two or three weeks to any treat adverse effects. If the patient does not tolerate the medication, a different acetylcholinesterase inhibitor is administered. If the condition of the patient is considered moderate to severe at diagnosis, acetylcholinesterase inhibitor is administered with or without memantine. If the patient’s condition deteriorates, the caregiver chooses to discontinue treatment.
Reference
Alzheimer's Association. (2012). 2012 Alzheimer's Disease Facts and Figures. New York: Public Policy Office.
State of California, Public Health Department. (2008). Guideline for Alzheimer’s Disease Management. California: Department of Public Health.
Stein, J., Schettler, T., Rohrer, B., Valenti, M., & Myers, N. (2008). Environmental Threats to Healthy Aging. Boston: GBPSR.
