Public awareness of AD increased significantly when Ronald Reagan (1911–2004), the 40th president of the United States (1981–1989), was diagnosed with the disease in 1994. He died from complications of AD at the age of 93. Alzheimer’s disease (AD) is the most common form of dementia in those aged 65 and older. It is an irreversible and incurable progressive neurological disease caused by the degeneration and eventual death of a large number of neurons (nerve cells) in several areas of the brain, accompanied by diminished brain size. AD usually occurs in old age and begins with short-term memory loss. This is followed by the slow progressive loss of memory and cognitive and intellectual functions, leading to the deterioration of physical functioning and incapacitation. Alzheimer’s rarely occurs before the age of 60. Early-onset AD, affecting people in their 30s, 40s, and 50s, accounts for only about 5% of total cases.
Risk Factors of Alzheimer’s Disease
The most significant risk factor for Alzheimer’s disease is advancing age. The risk of developing AD begins to rise after age 65 and rises sharply after age 75. There are various other possible risk factors:-
- About 25%of AD cases are considered to be familial, The remaining 75% of cases are sporadic Alzheimer’s Disease (SAD) with no clear family history.
- African American and Caribbean Hispanics are at a higher than normal risk for AD, particularly if they have a family history of the disease.
- A family history of Parkinson’s disease is a risk factor for AD.
- There is some evidence that neuronal damage from small strokes may be linked to AD.
- Studies have found a clear correlation between low educational and occupational attainment (employment in jobs that are not mentally challenging) and an increased risk for AD.
- High Blood Cholesterol levels may increase the rate of plaque deposition. high-cholesterol, high-fat diet may increase the risk of AD
- High Systolic Blood Pressure combined with high Blood Cholesterol levels increases the risk of AD by three-four fold.
- Obesity is a risk factor for AD
- High levels of an amino acid called homocysteine may be a risk factor for late-onset AD.
- Symptoms of AD may develop faster in people who have had a head trauma or hypothyroidism.
Causes of Alzheimer’s Disease
It is most likely caused by a combination of genetic and environmental factors. Viral, immunological, and/or biochemical etiologies have also been proposed. Genetics almost certainly plays a role, even in sporadic AD. Brain inflammation and restriction of blood flow to the brain may play a role in the development of beta-amyloid plaques and neurofibrillary tangles. Highly reactive molecules called free radicals damage all types of cells through oxidative processes, especially brain cells, which have lower levels of protective antioxidants.
Symptoms of Alzheimer’s Disease
AD symptoms can be grouped into three categories:
- Cognitive deficits or losses in brain function related to memory and learning. There are four major cognitive deficits associated with AD:
- Amnesia or memory impairment, including a loss of the sense of time.
- Aphasia or loss of language. Patients may not remember the names of objects and use words like ‘‘thing’’ or ‘‘it’’ instead. They may echo what other people say or repeat a word or phrase over and over. Sometimes patients lose all language except curses.
- Apraxia—the inability to perform voluntary movements. Patients with apraxia may have trouble putting on a hospital gown or brushing their teeth.
- Agnosia—the inability to recognize familiar people and places. Agnosia comes from the Greek word meaning ‘‘to not know.’’ Patients with agnosia may even fail to recognize their own face in a mirror.
- Behavioral and psychiatric symptoms of dementia or BPSD. Symptoms associated with BPSD (behavioral and psychiatric symptoms of dementia) include:
- Depression. Depression in A Disbelieved to result,at least in part, from lowered production of serotonin.
- Delusions,or a false belief that ismaintained even in the presence of evidence to the contrary. For example, AD patients may believe that someone is stealing from them when they cannot remember where they put something.
- Wandering.This behavior may result from becoming disoriented or lost, but sometimes AD patients wander for no apparent reason.
- Hallucinations, or sensory experiences that seem real. Although hallucinations can affect any of the senses, most are visual or auditory. For example, AD patients may say that they see Martians in the corner of the room or hear the voices of their long-dead parents. Like delusions, hallucinations are believed to be related to the deterioration of brain tissue. However sometimes they are caused by medications.
- Aggression—hitting, shoving, pushing, or threatening behavior.
- Agitation. Emotionally excited behavior (screaming, shouting, cursing, pacing, fidgeting, etc.) that is disruptive or unsafe may result from brain tissue damage or be a symptom of depression. It is thought that the emotional overreactions of AD patients are related to destruction of neurons in the amygdala of the brain.
- Difficulties with activities of daily life or ADL. ADL (activities of daily life) or personal-care symptoms include difficulties with:
- Eating, including simple cooking and washing dishes
- Shopping for groceries and other necessities
- Bathing, showering, or shaving
- Grooming and dressing in clothing appropriate for the weather and activity
- Other aspects of personal hygiene such as teeth brushing, denture cleaning, or washing hair
Key Early Warnings of Alzheimer’s Disease
Key warning signs of early-stage AD include:
- Repeatedly asking the same question
- Repeatedly telling the same story, word for word
- Memory loss that affects job performance
- Loss of initiative
- Inability to pay bills or balance a checkbook
- Misplacing commonly used personal or household objects
- Difficulty performing familiar tasks such as cooking, making repairs, or playing games like cards or checkers
- Poor or decreased judgment
- Problems with abstract thinking
- Getting lost in familiar surroundings
- Relying on others to make decisions or answer questions
- Disorientation of time and place
- Problems with language
- Mood or behavior changes
- Personality changes
- Neglecting personal hygiene—not bathing or changing clothes regularly
Tests for Alzheimer’s Disease
- Blood and urine tests are used to help rule out other causes of dementia.
- Genetic tests are available to detect genes known to cause AD.
- Several types of oral and written tests are used to help diagnose AD and track its progression, including tests of mental status, functional abilities, memory, verbal fluency, and concentration. In early-stage AD the results of these tests are usually within the normal range.
- The widely used mini-mental status examination (MMSE) is a screening test. It is not particularly sensitive for detecting cognitive impairment in well educated individuals who have previously functioned at a high level. It may also not yield accurate results for poorly educated individuals or cultural minorities.
- The clock test asks patients draw the face of a clock, possibly includinga specific time such as 3:20. Patients with AD often put the numbers out of order, put them all in one part of the clock face instead of evenly spaced, or have difficulty drawing in the clock hands.
- Occasionally the cerebrospinal fluid is tested for the levels of two proteins, Tau and a specific beta-amyloid proteinfragmentcalledAbeta42.Increased Tauprotein and decreased A beta 42 in the cerebrospinal fluid are indicative of AD.
Treatment of Alzheimer’s Disease
Although there is no cure for Alzheimer’s disease, early diagnosis and prompt intervention can slow its progression and enable patients to function independently for a longer period. Health care professionals usually assess a patient’s ADL to determine what type of care is needed. The mainstay of treatment is the establishment of daily routines, good nursing care and/or home-care strategies, and providing physical and emotional support. In the initial stages, counseling by a psychologist or an AD support group is recommended.