Myths Surrounding Alzheimer's Disease
By: Melissa Medalie
Updated: February 2, 2009
In-depth interview with Dr. Maria Carillo
RESEARCH SUMMARY
BACKGROUND: There are many myths surrounding Alzheimer's disease, the most common form of dementia. Many think memory loss is a natural part of aging, but according to the Alzheimer's Association, severe memory loss is now recognized by experts as an indication of a serious illness. Many also don't realize the disease is fatal. The truth: It will kill you. It robs patients of brain cells, which leads to memory problems, erratic behaviors and the inability of the body to function properly. It also takes away your identity and ability to relate to others.
PROTECTING YOURSELF: There is currently no cure for the disease, and in only half of the patients who take the available FDA-approved Alzheimer's drugs, symptoms slow or stop for six to 12 months. Experts say, however, there are ways to protect yourself. For example, Alzheimer's disease is directly linked to cardiovascular and metabolic health. Obese people are twice as likely to develop dementia and those with heart disease have a much higher risk of AD. Recent research shows people with high blood pressure, one of the precursors of heart disease, are up to 600 percent more likely to develop dementia. The Alzheimer's Society of the United Kingdom says treating the condition in midlife can cut the number of deaths from dementia by up to 15,000 people a year. Other studies show having high cholesterol increases someone's chance of developing dementia by 43 percent and having diabetes increases it by 65 percent.
High glucose levels are also linked to the debilitating disease. A nine-year study of 1,173 diabetes-free people over age 75 showed those with high glucose levels had a 77 percent greater chance of getting AD. Insulin levels decrease with age, making it more difficult for glucose to enter cells, which causes a spike in glucose levels. That results in more waste products like free radicals, in the cells, which can harm blood vessels.
Some experts say Alzheimer's is a new type of diabetes. In the past few years, researchers at Rhode Island Hospital and Brown Medical School have discovered that insulin and insulin receptors are considerably reduced in the brains of early-stage Alzheimer's patients. As the disease progresses, insulin levels continue to deplete. They also found that a deficiency in the neurotransmitter acetylcholine, a characteristic of the disease, is associated with insulin loss. They went on to illustrate that potential Alzheimer's treatments are those that target insulin and its action on the brain. "We have demonstrated that a loss of insulin in the brain triggers the onset of Alzheimer's, probably because as the brain loses insulin, the cells that require insulin to function and survive also eventually die," Suzanne M. de la Monte, M.D., senior author of the study, a neuropathologist at Rhode Island Hospital and a professor of pathology at Brown Medical School in Providence, R.I., was quoted as saying. "The consequences are increased oxidative stress, brain deterioration, loss of cognitive function, and a buildup of plaques and tangles in the brain -- all hallmarks of Alzheimer's."
GIVE YOUR BRAIN A BOOST: GET MOVING! Experts say exercise can protect you from Alzheimer's disease, but according to the Centers for Disease Control (CDC), only a small number of older adults follow the recommended 30 minutes or more, five days a week guideline. Twenty-eight to 34 percent of adults aged 65 to 74 and 35 to 44 percent of adults over age 75 do not engage in leisure-time physical activity. One reason exercise may prevent AD is by thwarting the buildup of plaque, as shown in mice injected with a gene predisposing them to plaque accumulation. In addition, exercise combats depression. Research by Rush Alzheimer's Disease Center revealed lonely people are twice as likely to develop AD. According to John J. Ratey, M.D., author of Spark: The Revolutionary New Science of Exercise and the Brain, exercise causes a rush of the neurotransmitter dopamine, which is associated with feelings of pleasure. Dopamine has been shown to slow metabolism in areas of the brain linked to cognition, but with age, dopamine levels taper off.
