Can Ginkgo Biloba Prevent or Slow Down Alzheimer's Symptoms

Ginkgo biloba is a plant extract containing several compounds that may have positive effects on cells within the brain and the body. Ginkgo biloba is thought to have both antioxidant and anti-inflammatory properties, to protect cell membranes and to regulate neurotransmitter function. Ginkgo has been used for centuries in traditional Chinese medicine and currently is being used in Europe to alleviate cognitive symptoms associated with a number of neurological conditions.

The difficulty of stating absolutes about ginkgo's effectiveness is that research findings vary in their results. Some clinical trials do show some small positive effects on people with Alzheimer's disease, other studies no effect.

Gold, Carhill and Wenk (2003) say in their prospective study (extensive review) that, "Our overriding impression, however, is that we do not have enough information to say conclusively whether ginkgo does or does not improve cognition".

The final results of a large, multicenter Phase III study published in the Journal of the American Medical Association  (November 19, 2008) has also showed that gingko was no better than placebo in delaying changes in memory, thinking and personality and had no impact on the development of dementia and Alzheimer’s.

The Gingko Evaluation and Memory (GEM) Study enrolled 3,000 individuals age 75 or older who either had no dementia or mild cognitive impairment. Participants were randomly assigned to receive twice daily doses of either a placebo or 120 milligrams of gingko biloba extract. They were followed up every six months for six years.

Researchers found no statistical difference in dementia or Alzheimer’s rates between the groups. Among those receiving gingko, 277 developed dementia. Among those receiving placebo, 246 developed dementia. Mortality rates were also similar.

"It just continues to show that in properly designed, placebo-controlled studies, we can't seem to find an effect for ginkgo biloba," says Lon Schneider, an Alzheimer's and gerontology expert at the University of Southern California. The size of this study is larger than all previous ginkgo biloba studies combined, he says.

Douglas MacKay, vice president for scientific and regulatory affairs at the Council for Responsible Nutrition, a supplement industry trade group, disputes the study's findings.

"There is a large body of previously published evidence, as well as ongoing trials, which suggest that ginkgo biloba is effective for helping to improve cognitive impairment in older adults," he says.

U.S. sales for ginkgo biloba were $99 million in 2008, down 8% from 2007 but still placing it the 8th most popular herb and botanical that the Nutrition Business Journal tracks.

Is Ginkgo Harmless?

The findings strongly argue against the use of ginkgo biloba for the prevention of mental decline in older populations, claims professor Lon S. Schneider, MD from University of Southern California psychiatry and neurology. He notes that the GEM study is far larger and longer than any previous placebo-controlled ginkgo biloba trial. "The message to take from this is that this intervention doesn't work," he says.

In an editorial accompanying the study, Schneider pointed to earlier trials suggesting a slight increase in strokes and mini-strokes in patients taking ginkgo biloba.

In the GEM study, there was no difference in heart attack or ischemic strokes between the ginkgo and placebo-treated patients. Ischemic strokes, the most common type of stroke, are caused by a blockage in an artery that supplies blood to the brain. There were more hemorrhagic (bleeding) strokes in the ginkgo group, but the overall number of cases was small and the difference was not found to be significant.

"The potential adverse effects of ginkgo biloba extract illustrate why it is untenable to recommend a drug or nutraceutical in the absence of efficacy evidence simply because it could possibly help and initially appears harmless," Schneider writes.

Although he acknowledges that the GEM study was well designed, Mark Blumenthal, who is founder and executive director of the American Botanical Council, tells that the trial does not represent the last word on ginkgo biloba and dementia.

"There are other trials that will be coming out," he says. "Whether or not they will show a positive result or not remains to be seen." He cited several studies suggesting a role for ginkgo biloba in slowing the progression of dementia in elderly people already experiencing cognitive decline. "In reporting the news that ginkgo biloba didn't work for prevention in this study, it is important not to mislead people into thinking that there is no evidence to support treatment," he says.

About Ginkgo Biloba

Ginkgo Biloba is sometimes called a living fossil and the only surviving member of the Ginkgo family. It is one of the oldest living tree species, a deciduous conifer, dating back over three-hundred million years. Individual trees may live for one thousand years, as they are resistant to viruses, fungi, insects, pollution and even radiation, and they may reach 122 feet in height. Native to China, it has been included in Chinese herbal medicine's repertoire for almost five thousand years, where it was used for respiratory tract ailments and for memory loss in older adults. The trees were introduced to Europe in 1730 and the United States in 1784 as ornamentals, but since the 1980s, Western medical interest in the plant has grown dramatically since its potent actions on the cardiovascular system were identified. Different parts of the plant have different properties with different medical applications. Most commercial growth of Ginkgo is centered in plantations in South Carolina, France and China. Some of Ginkgo's constituents include amino acids, tannins, quercetin, beta-carotene, flavone glycosides, bioflavones, sitosterol, lactones, anthocyanin, calcium, iron, magnesium, manganese, phosphorus, potassium, zinc, B-vitamins and vitamins A and C. Ginkgo is now among the leading prescription medicines in both Germany and France. 

Sources and Additional Information:

http://www.alz.org/alzheimers_disease_alternative_treatments.asp

http://alzheimers.about.com/od/treatmentoptions/a/ginkgo_biloba.htm

http://www.usatoday.com/news/health/2009-12-30-ginkgo30_ST_N.htm

http://www.webmd.com/alzheimers/news/20081118/ginkgo-biloba-doesnt-prevent-dementia

Is there a Link Between Level of Education and Alzheimer's Disease?

An interesting association between low education level and Alzheimer’s disease has been noticed by the professional, however the exact reason for this phenomenon is not clear. Some scientists believe it has to do with synaptic concentration (the amount of alternative routes a neuron can use to communicate with other neurons). The suggestion is that the higher your education level, the more synaptic connections your neurons have had to make in order to process all the information stored in your brain, and this is considered as cognitive or neurological reserve.

This threshold model proposes that a more educated person might have more synapses to lose before behavioral problems how up or that they exhibit dementia only if their cognitive reserve capacity falls below a specific threshold.

A 2008 research confirmed the theory that education can delay the onset of the dementia and cognitive decline that are characteristic of the disorder. Scientists at the Alzheimer's Disease Research Center at Washington University School of Medicine in St. Louis found that some study participants who appeared to have the brain plaques long associated with Alzheimer's disease still received high scores on tests of their cognitive ability. Participants who did well on the tests were likely to have spent more years in school.

"The good news is that greater education may allow people to harbor amyloid plaques and other brain pathology linked to Alzheimer's disease without experiencing decline of their cognitive abilities," says first author Catherine Roe, Ph.D., research instructor in neurology.

Roe and her colleagues at the Alzheimer's Disease Research Center used the study participants' education levels to approximate a theoretical quality called cognitive reserve: improved abilities in thinking, learning and memory that result from regularly challenging and making use of the brain. Neurologists have long speculated that this quality, roughly equivalent to the benefits that accrue in the body via regular physical exercise, can help the brain cope with the damage caused by Alzheimer's disease.

Doctors still cannot conclusively diagnose Alzheimer's disease in any manner other than post-mortem brain examination. But Washington University scientists have shown that an imaging agent for positron emission tomography scans, Pittsburgh Compound B (PIB), can reveal the presence of amyloid plaques, a key brain change that many neurologists suspect either causes Alzheimer's or is closely linked to its onset.

In addition to scanning the participants' brains with PIB, the participants took several tests that assessed their cognitive abilities and status. They also ranked their educational experience: high-school degree or less, college experience up to an undergraduate degree, and graduate schooling.

As expected, those whose brains showed little evidence of plaque buildup scored high on all the tests. But while most participants with high levels of brain plaque scored poorly on the tests, those who had done postgraduate work still scored well. Despite signs that Alzheimer's might already be ravaging the brains of this subgroup, their cognitive abilities had not declined and they had not become demented.

The obtained results were reproduced by the recent 2009 study at the Department of Psychiatry, Klinikum rechts der Isar, Technische Universität München, investigated the effects of formal education on the symptoms of Alzheimer's disease. They researchers were able to show that education diminishes the impact of Alzheimer's disease on cognition even if a manifest brain volume loss has already occurred. Dr. Robert Perneczky explains: "We know that there is not always a close association between brain damage due to Alzheimer's disease and the resulting symptoms of dementia. In fact, there are individuals with severe brain pathology with almost no signs of dementia, whereas others with only minor brain lesions exhibit a considerable degree of clinical symptoms."

These phenomena are often ascribed to the theoretical concept of cognitive reserve. A high level of cognitive reserve results in a strong individual resilience against symptoms of brain damage; cognitive reserve can therefore be seen as protective against brain damage.

However, while education level and brain activity has proven to allow certain delay (protection) for the Alzheimer’s disease development, but it is not able to slow memory loss once it starts, says another study. Reporting in the Feb. 3, 2009 issue of Neurology, scientists say they found that education does not appear to protect against how fast people lose memory once forgetfulness begins.

"This is an interesting and important finding because scientists have long debated whether aging and memory loss tend to have a lesser effect on highly educated people," says study author Robert S. Wilson, PhD, with the Alzheimer's Disease Center at Rush University Medical Center in Chicago. "While education is associated with the memory's ability to function at a higher level, we found no link between higher education and how fast the memory loses that ability."

He and colleagues tested the thinking skills of 6,500 people from the Chicago area with an average age of 72 and varying levels of education. The level of education of people in the study ranged from eight or fewer years of school to 16 or more years. Interviews and tests about memory and thinking functions were given every three years, up to 14 years.

When the study started, people with more education were found to have better memory and thinking skills than those with lesser education. The results remained the same regardless of other factors related to education, such as job status, race, and the effects of practice with the tests.

Further analysis, however, showed that the "rate of cognitive decline at average or high levels of education was slightly increased" during early years of follow-up study, but then decreased slightly later, compared to people with low levels of education. "The results suggest that education is robustly associated with level of cognitive function, but not with rate of cognitive decline," they conclude.

Sources and Additional Information:

http://mednews.wustl.edu/news/page/normal/12951.html

http://www.webmd.com/alzheimers/news/20090202/education-protects-against-alzheimers

http://www.medicalnewstoday.com/articles/164056.php

http://esciencenews.com/articles/2009/08/11/formal.education.lessens.impact.alzheimers.disease

17 Myths and Facts about Alzheimer's Disease

According to the Alzheimer's Association, about 5 million Americans are living with Alzheimer's disease today -- a figure that's expected to increase as the baby boom generation ages. The disorder causes neurons, or cells in the brain, to malfunction and die. The onset of Alzheimer's usually happens after the age of 60, but early-onset Alzheimer's can affect younger people. Though scientists have learned much about the illness in the last decade, many questions remain about the causes, stages, and treatment of Alzheimer's. It's not surprising, then, that patients' and caregivers' understanding of the disease is often off-target. Myths and half-truths only add to fear of the disease, which can prevent people from getting help that could improve their quality of life.

Here are 17 common myths about Alzheimer's -- busted.

Myth: If you're forgetful, you're getting Alzheimer's disease.

Reality: Memory loss is a key symptom of Alzheimer's, but forgetfulness doesn't mean you have the disease. Even if your forgetfulness is due to more than simple aging, there are still many causes for dementia that lead to a decrease in cognitive function; physicians will make an Alzheimer's diagnosis only after other conditions have been ruled out.

Myth: Memory loss is a natural part of aging.

Reality: In the past people believed memory loss was a normal part of aging, often regarding even Alzheimer’s as natural age-related decline. Experts now recognize severe memory loss as a symptom of serious illness. Whether memory naturally declines to some extent remains an open question. Many people feel that their memory becomes less sharp as they grow older, but determining whether there is any scientific basis for this belief is a research challenge still being addressed.

Myth: Most people with Alzheimer’s are oblivious to their symptoms.

Reality: Typically someone in the early stage of Alzheimer’s disease does realize, at least part of the time, that something’s wrong. (Whether they recognize it as Alzheimer’s is another matter.) Most people with the disorder are aware that they’re experiencing memory lapses, for example, or that they’re starting to have trouble doing certain familiar tasks (following a favorite card game, cooking a particular recipe). Insight varies by individual, and the degree of awareness can shift from day to day.

Depending on their level of awareness and attitude toward correction, people with Alzheimer’s may appreciate being gently told when they make a mistake due to memory loss, disorientation, or another disease symptom. On the other hand, self-awareness of symptoms can make someone frustrated, angry, scared, or socially withdrawn. As the disease progresses and symptoms worsen, awareness of the situation is likely to decline.

Myth: An x-ray of the brain can diagnose Alzheimer's disease.

Reality: Unfortunately, the brain changes that cause Alzheimer's can not be seen with an x-ray. However, promising new tests using MRI and other imaging techniques are in development. Physical examination is important to rule out other conditions; the disease is then most often diagnosed by a series of tests of mental status.

Myth: If you have a family member with Alzheimer's, you'll get it, too.

Reality: In rare cases, early-onset Alzheimer's is inherited through genes. This familial form of Alzheimer's causes just 7% of all Alzheimer's cases. Genetics plays a small role for those people who don't have this form of Alzheimer's but who do get the disease later in life. If you have a parent, brother or sister with the disease, you have a slightly higher risk of getting it.

Myth: Aluminum in products we use causes Alzheimer's.

Reality: Most of us use products every day that contain aluminum. Food prepared in aluminum pots and pans carries trace amounts of the metal. Many underarm antiperspirants also contain aluminum. There is no scientific evidence that aluminum exposure causes Alzheimer's. Although the disease's exact cause is unknown, most research suggests that several factors, such as age, genetic susceptibility and overall quality of health, ultimately contribute to whether or not someone develops the disease.

Myth: Aspartame causes memory loss.

Reality: This artificial sweetener, marketed under such brand names as Nutrasweet and Equal, was approved by the U.S. Food and Drug Administration (FDA) for use in all foods and beverages in 1996. Since approval, concerns about aspartame's health effects have been raised.  According to the FDA, as of May 2006, the agency had not been presented with any scientific evidence that would lead to change its conclusions on the safety of aspartame for most people. The agency says its conclusions are based on more than 100 laboratory and clinical studies.

Myth: Flu shots increase risk of Alzheimer’s disease

Reality: A theory linking flu shots to a greatly increased risk of Alzheimer’s disease has been proposed by a U.S. doctor whose license was suspended by the South Carolina Board of Medical Examiners. Several mainstream studies link flu shots and other vaccinations to a reduced risk of Alzheimer's disease and overall better health. 

• A Nov. 27, 2001, Canadian Medical Journal report suggests older adults who were vaccinated against diphtheria or tetanus, polio, and influenza seemed to have a lower risk of developing Alzheimer’s disease than those not receiving these vaccinations.
• A report in the Nov. 3, 2004, JAMA found that annual flu shots for older adults were associated with a reduced risk of death from all causes.

Myth: Silver dental fillings increase risk of Alzheimer's disease.

Reality: According to the best available scientific evidence, there is no relationship between silver dental fillings and Alzheimer's. The concern that there could be a link arose because "silver" fillings are made of an amalgam (mixture) that typically contains about 50 percent mercury, 35 percent silver and 15 percent tin. Mercury is a heavy metal that, in certain forms, is known to be toxic to the brain and other organs.

Many scientists consider the studies below compelling evidence that dental amalgam is not a major risk factor for Alzheimer's. Public health agencies, including the FDA, the U.S. Public Health Service and the World Health Organization, endorse the continued use of amalgam as safe, strong, inexpensive material for dental restorations.

• March 1991, the Dental Devices Panel of the FDA concluded there was no current evidence that amalgam poses any danger.
• National Institutes of Health (NIH) in 1991 funded a study at the University of Kentucky to investigate the relationship between amalgam fillings and Alzheimer's. Analysis by University statisticians revealed no significant association between silver fillings and Alzheimer's. 
• October 30, 2003, a New England Journal of Medicine article concluded that current evidence shows no connection between mercury-containing dental fillings and Alzheimer's or other neurological diseases. 

Myth: All old people have Alzheimer's disease.

Reality: Even though age is an important risk factor for Alzheimer's, the majority of old people do not have the disease. It's important to note that normal aging doesn't necessarily include dementia or Alzheimer's.

Myth: Alzheimer’s disease affects only old people.

Reality: Though the majority of patients with AD are above 65 years old, there are also cases, when the disorder affects people in their 50^th or even 40^th. That is why it is important to understand that the symptoms of AD, such as memory problems, are not part of normal aging. The earlier the disorder is detected – the more effective management of it could be.

Myth: Men are at higher risk of developing Alzheimer's than women.

Reality: Alzheimer's disease affects both men and women that is true but it is believed to be more common in women. The reason for this claim is based on the unrelated fact that women live longer than their opposite sex so are more likely to develop the disease at some stage of their life.

Myth: Alzheimer's disease is preventable.

Reality: There is no treatment that can prevent Alzheimer’s disease. There is, however, a growing amount of evidence that lifestyle choices that keep mind and body fit may help reduce the risk. These choices include being physically active; eating healthy foods including fresh fruits, vegetables and fish; keeping your brain challenged; reducing stress, keeping an eye on your blood pressure, blood sugar and cholesterol levels; avoiding traumatic brain injury; and keeping socially active.

Myth: Alzheimer’s disease can be cured with pills, herbs, or supplements.

Reality: Currently there is no cure for Alzheimer’s disease. Modern pharmaceutical options can only slow down the progression of the disorder. The effect of herbs, such as ginkgo biloba, vitamins E, B and C, as well as folic acid and selenium, on patients with Alzheimer’s disease is also not yet fully understood, and the history of their use for AD treatment contains many controversies and vagueness. There are some evidences of beneficial effect of the said remedies, but it is definitely too early to claim that they are able of curing Alzheimer’s disease.

Myth: Alzheimer’s disease makes people hostile, violent, and aggressive.

Reality: As a matter of fact, Alzheimer’s disease affects different people in different ways. Some patients develop certain changes in their behavioral patterns, like becoming violent or aggressive, and some do not. It is important to understand that the symptoms of AD may be frightening and scary first of all for a patient himself; that is why it is important to educate yourself, as well as a patient, about the disorder, and what to expect from it in order to prevent aggressive responses from a patient. Try to improve his usual surroundings in accordance with his specific demands, do not expose him to stressful events, and make him feel comfortable even with his gradually decreased abilities.

Myth: People with Alzheimer's disease cannot understand what is going on around them.

Reality: Some people with Alzheimer's disease understand what is going on around them; others have difficulty. The disease does affect a person's ability to communicate and make sense of the world around them, although it affects each person differently. When we assume someone does not understand, feelings can be hurt unintentionally. The fact is a person with Alzheimer's disease is still the same person as before and needs to be treated with dignity and respect.

Myth: Life with Alzheimer's disease isn't worth living.

Reality: There is no single course for Alzheimer's disease, which typically can be a part of a person's life for many years. Memory loss and communication problems can cause frustration and anger. With help, though, a person with Alzheimer's can have a meaningful and productive life. According to the National Institute of Neurological Disorders, several medications have been approved for early- and middle-stage Alzheimer's, including Aricept(donepezil), Exelon (rivastigimine),  Namenda (memantine), and Razadyne (galantamine; formerly Reminyl). A number of other medications can be used to control anxiety, depression, sleeplessness, and agitation, any or all of which may accompany the disease.

Sources and Additional Information:

http://alzheimers.about.com/lw/Health-Medicine/Conditions-and-diseases/Myths-and-Realities-of-Alzheimers-Disease.htm

http://www.pillwatch.com/info/alzheimers-disease-myths-and-realities.html

http://www.alz.org/alzheimers_disease_myths_about_alzheimers.asp

http://www.memorystudy.org/alzheimers_myths.htm

http://www.poststat.net/rightathome/pub.59/issue.1059/article.4339/