“How would you define dementia?” Dr. Dheeraj Mahajan, medical director of geriatrics, asks the audience at this month’s Learning Café.
Responses range from forgetting one’s keys to an inability to complete simple activities that constitute daily living, such as dressing and eating. One woman suggests that dementia means forgetting what you ate, where you are in space or time, or who you are.
“I hear a lot of the word ‘forgetting,’” Dr. Mahajan says. He defines dementia as severe memory loss that prevents people from conducting the simplest of daily activities.
“Once considered rare, dementia is now seen as a major public health problem seriously affecting millions of Americans and their families,” he says. “It’s an irreversible, progressive brain disease. We cannot yet reverse it, but we can slow it down or halt it.”
Types of dementia include:
- Lewy body dementia—The second most common type of dementia, LBD affects an estimated 1.3 million individuals and their families, but is widely underdiagnosed. It causes a progressive decline in mental abilities and may lead to visual hallucinations. People with LBD may develop rigid muscles, slowed movements and tremors. The disease is caused by abnormal, round structures in the parts of the brain responsible for thinking and movement.
- Creutzfeldt-Jakob disease—This rare form of dementia affects one in every 1 million people per year worldwide. Onset of the disease happens quickly, resulting in death among 90 percent of individuals within the first year. CJD is the most common in the family of diseases called “transmissible spongiform encephalopathies.” It may lead to failing memory, behavioral changes, lack of coordination, visual disturbances, involuntary movements, blindness, weakness of extremities, and coma.
- Huntington's disease—This genetically programmed degeneration of brain cells leads to uncontrolled movements, loss of intellectual faculties, and emotional disturbance. One out of every 10,000 Americans has HD, and every child with a parent who has HD has a 50/50 chance of developing the disease.
- Parkinson's disease—Most often developed after age 50, Parkinson’s leads to tremors and difficulties with walking, movement and coordination. This occurs when the nerve cells in the brain that make dopamine (the chemical used in controlling muscle movement) slowly deteriorate. Nearly 1 million people in the U.S. live with Parkinson’s.
Dementia takes its most common form, however, in Alzheimer’s disease. A progressive disorder that results in severe memory loss, Alzheimer’s accounts for 50 to 80 percent of all dementia cases. Scientists estimate that 4.5 million people have Alzheimer’s, and their care costs have climbed to $100 billion annually.
“The sad part is that we still have to go a long way to find what is causing it,” Dr. Mahajan says. “What we know now is that we have to find it early and do things to preserve the memory.”
So far, researchers have concluded that two basic biological factors cause dementia: plaques and/or tangles (clumps of nerve cells unable to convey information) gathering in the brain. Affected regions of the brain begin to shrink as nerve cells die.
Screening tests exist, which show if certain areas of the brain are shrinking. Though these tests are expensive, Dr. Mahajan says they can lead to preventative therapies that can extend memory for 15 years. The therapies may include drugs such as Aricept, Exelon or Razadyne—and they will involve brain exercises to help keep the mind sharp.
“The point is not adding years to your life, but adding life to your years. It’s not like I’m going to make you live to 90 years old with somebody feeding you. You’re going to do what you do today and feel good about your life,” he says.
For more information on dementia and specifically Alzheimer’s disease, visit the Alzheimer’s Association at www.alz.org. You also can call Dr. Mahajan at (773) 878-8700.