Alzheimer's disease (AD), the most common cause of dementia, is the loss of intellectual and social abilities severe enough to interfere with daily functioning.
AD which usually develops in individuals aged 65 or more, slowly leads to memory impairment, behavioral changes and dementia; it affects how people understand, think, remember and communicate.
Researchers believe the number of AD cases will quadruple to around 106 million people by the year 2050. More than half of the world's AD sufferers are in Asia and the number is predicted to rise to 62.8 million by 2050.
Many believe Alzheimer's begins to attack the brain years before symptoms appear, therefore determining what causes the disease and who's susceptible to it are critical in preventing or slowing down the disease.
Etiology While the causes of Alzheimer's are not very clear, it is obvious that the neurons in certain brain locations begin to die in sufferers leading to lowered neurotransmitter levels. Dr. Alois Alzheimer, a German neurologist, discovered the disease in 1906 while examining the brain of a woman who had died after years of progressive dementia.
He found abnormal clumps and irregular knots in the woman's brain tissue. Today, these clumps (now called plaques) and knots (now called tangles) are considered hallmarks of Alzheimer's disease.
Alzheimer's sufferers tend to have lower SORL1 levels in their blood which in turn leads to the deposition of greater amounts of amyloid beta peptide (plaques) in brain nerve cells and the inflammatory response subsequently causes Alzheimer's.
Risk Factors Alzheimer's is a complex disease caused by a combination of factors including infection, reduced circulation and genetic susceptibility. The main risk factors include, - Age.
Alzheimer's usually affects people older than 65, but can also affect younger individuals. The number of affected persons, in individuals beyond the age of 65, doubles every 5 years. The risk is increased by 50% in individuals older than 85 years old. - Heredity.
The risk of developing Alzheimer's appears to be slightly higher if a first-degree relative has the disease. Although the role of genetics is unexplained in AD, there are a number of genetic mutations believed to be responsible for increasing the risk of the disease in certain families. - Gender.
The disease is about twice as common in women as they live longer. - Lifestyle. Factors like high blood pressure, high cholesterol and poorly controlled diabetes, which increase heart disease risk, are responsible for developing Alzheimer's.
It is believed that remaining mentally active throughout one's life, especially in the later years, reduces the risk of AD. - Obesity. High insulin levels in obese people can increase the risk of AD. Diabetics are also at a higher risk for the disease. - Nutritional deficiencies. People with AD tend to have low levels of vitamin B12, B3 and Zinc. - Education levels.
Some researchers claim the more educate a person is the less likely he/she is to develop AD, as they have more brain synapses. - Mood disorders. People who tend to experience psychological distress and negative emotions such as depression and anxiety are more prone to develop AD. - Toxicity.
Many believe overexposure to certain trace metals or chemicals (deposits of aluminum in the brain) can cause Alzheimer's. - Head injury. Serious traumatic head injuries (a concussion with a prolonged loss of consciousness) have been linked to future Alzheimer's. - Hormone replacement therapy (HRT).
The exact role of hormone replacement therapy in the development of dementia is not yet clear. - Down syndrome. Individuals with Down syndrome experience premature aging; therefore, they are at a higher risk for age-related health conditions like Alzheimer's. Signs and Symptoms Alzheimer's disease, an irreversible, progressive, degenerative brain disease, causes more than simple forgetfulness that everyone may experience.
As the early Alzheimer's symptoms progress slowly, diagnosis is often delayed. Individuals who are frightened by the signs keep them hidden; therefore families often fail to realize the problem until it is too late.
The course of the disease varies from one person to another. Eight years is the average length of time between the diagnosis of Alzheimer's to death. Survival begins to decline three years after diagnosis, however many live more than a decade with the disease.
Alzheimer's which may start with slight memory loss and confusion, eventually leads to irreversible mental impairment that destroys a person's ability to remember, reason, learn and imagine. Most AD sufferers show certain symptoms:
1. Memory loss affecting daily function- At its onset, Alzheimer's disease is marked by periods of forgetfulness, especially of recent events or simple directions. But what begins as mild forgetfulness persists and worsens. AD sufferers may repeat actions and forget conversations or appointments. They frequently forget names even the names of family members and everyday objects. As Alzheimer's disease progresses, severe short term memory loss becomes more apparent. Individuals are able to recall past events but are incapable of remembering recent events.
2. Problems with abstract thinking- People with Alzheimer's initially have trouble balancing their checkbook, eventually they have difficulty recognizing and dealing with numbers, and finally they cannot remember what the numbers mean.
3. Misplacing things- Sufferers routinely misplace things, often putting them in illogical locations: an iron in the freezer or a wristwatch in the sugar bowl.
4. Difficulty in performing familiar tasks- AD patients have trouble with routine tasks requiring sequential steps, such as preparing a meal. Advanced cases forget how to do even the most basic tasks.
5. Disorientation of time and place- AD sufferers often lose their sense of time and date, and find themselves lost in familiar surroundings.
6. Problems with language- Sufferers forget simple words or substitute words, making sentences difficult to understand. Eventually, reading and writing are also affected.
7. Poor or decreased judgment- Alzheimer's is characterized by greater difficulty in doing things that require planning, decision making and judgment. Solving everyday problems, like what to do when food is burning on the stove, becomes increasingly difficult and sooner or later impossible. These individuals also do not pay much attention to their hygiene and health and are not dressed according to season.
8. Extreme changes in mood and behavior- Patients exhibit varied mood swings for no apparent reason.
9. Personality changes- AD patients become confused, suspicious or withdrawn. They may also become apathic, fearful or act out of character. Sufferers may express distrust in others, show increased stubbornness or withdraw from society. Depression and restlessness often coexists with Alzheimer's disease.
10. Loss of initiative- In advanced stages sufferers become passive, and require cues and prompting to become involved. They wander without purpose and experience incontinence.
A decline in the sense of smell often occurs as early as two years prior to the start of mental decline in AD patients. The rate at which the sense of smell is lost can predict how rapidly cognitive functioning is lost.
Diagnosis Alzheimer's disease often goes unrecognized or is misdiagnosed in its early stages. Early and accurate diagnosis of AD gives patients and their families, time to plan for the future.
There is currently no single test which can accurately diagnose Alzheimer's disease, therefore a range of assessments and laboratory tests are used to rule out other possible diseases causing memory loss (undetected strokes, Parkinson's disease, several medications).
Taking a complete medical history, performing thorough physical and mental examinations, and neuropsychological testing along with certain laboratory tests and brain imaging can help doctors rule out other potential causes of the dementia.
Genetic testing for Alzheimer's can tell whether or not a person carries the genetic mutations believed to be associated with the disease.
Prevention Delaying the onset of Alzheimer's is an important step in fighting the disease. While there is no proven way to prevent AD, there are a number of recommendations: - Healthy aging. Scientists believe improving the cardiovascular health by losing weight, exercising and controlling high blood pressure can help prevent Alzheimer's disease. - Nonsteroidal anti-inflammatory drugs (NSAIDs).
NSAIDs such as ibuprofen (Advil and Motrin), naproxen sodium (Aleve) and indomethacin (Indocin) can reduce the risk of developing Alzheimer's. - Statins.
These drugs (atorvastatin (Lipitor), rosuvastatin (Crestor) and simvastatin (Zocor)) are used to lower cholesterol levels and reduce the risk of Alzheimer's disease. - A selective estrogen receptor molecules (SERMs) called raloxifene (Evista) is used to protect against bone loss associated with osteoporosis; it lowers the risk of developing mild cognitive impairment which precedes Alzheimer's. - Healthy diet.
A well-balanced diet rich in fiber, antioxidants and polyphenols (fruit and vegetables) can help delay the onset of AD. - Herbal remedies. Herbs such as Butcher's broom, Ginkgo biloba extract, Kava Kava, Curcumin, rosmarinic acid, the Chinese herb (qian ceng ta) and valerian root are effective in preventing AD. - Avoiding alcohol, cigarette smoke, processed foods, environmental toxins especially aluminum and mercury. - Biking, walking, swimming and golf are the most effective sports which can reduce the risk of developing Alzheimer's disease. - Mental fitness.
Many believe advanced education, lifelong mental exercise (board games, cross word puzzles, reading) and learning can promote the growth of additional synapses and delay the onset of dementia.
Researchers claim being bilingual (speaking at least two languages every day for 50 years or more) can reduce the risk of developing Alzheimer's. - Many drugs should be avoided as they adversely affect CNS by increasing confusion and lethargy.
These drugs include sedatives (benzodiazepines), anticholinergic drugs (tricyclic antidepressants), antihistamines, antipsychotics and benztropine.
Treatment Although there is no cure for Alzheimer's, there are medications which can help improve the quality of life in sufferers by slowing down the process of the disease and improving symptoms secondary to AD such as insomnia, wandering, anxiety, agitation and depression. - Cholinesterase inhibitors This group of medications (donepezil (Aricept), rivastigmine (Exelon) and galantamine (Reminyl)) improves the brain's neurotransmitters levels.
Donepezil can delay the onset of Alzheimer's for about a year in people who have mild cognitive impairment (MCI) in the absence of dementia. - Memantine (Namenda) It is the first drug approved to treat moderate to severe stages of Alzheimer's.
Complications In advanced stages sufferers may lose all ability to care for themselves which makes them more prone to additional health problems such as pneumonia, infections and fractures.