"A Beautiful Mind," last year's Academy Award winner for Best Picture, took us on an extraordinary journey into the mind of a brilliant man suffering from mental illness. As viewers, we were able to appreciate, admire, and sympathize with John Nash as he struggled to accept his illness. The movie delivered an important lesson…Mental illness can affect anyone and, if left untreated, it can harm both the mind and body.

As portrayed in the movie, mental illness in today's society is a serious and often undiagnosed health problem currently affecting the country's aging population. Unfortunately, even when mental illness is accurately diagnosed, it is often under treated. This neglect is due to a combination of factors, including restrictions on Medicare coverage, lack of education and the stigma that is still associated with mental illness. The impact that this can have on the elderly is significant.

"Most folks go through life being relatively healthy and then in later years, when they have psychiatric disorders such as anxiety, Alzheimer's, or depression, it's a tremendous burden for the patient and families to deal with," adds Dr. Christopher Colenda, chair of the Department of Psychiatry at Michigan State University and treasurer-elect of the American Association for Geriatric Psychiatry. "This is not how they've conceived their retirement years."

But unfortunately, this is the reality for many. Depression and related diseases affect approximately 15 out of every 100 adults over the age of 65 in the U.S. Due to the coming Baby Boom, these numbers are destined to rise in the coming years, making a major impact on our healthcare system.

"Mental illness increases disability, suicide rates, and institutionalization," says Dr. Kenneth Sakauye, professor of psychiatry at Louisiana State University and chair of the American Psychiatric Association Council on Aging.

While mental illness knows no age barriers, the elderly are most susceptible to the "three D's" -dementia, delirium, and depression. Currently, the "three D's" are treated with prescription medications, as opposed to other psychiatric methods.

Dementia, which includes Alzheimer's Disease, increases with age, and affects a high percentage of people in hospitals and nursing homes. Dementia can be treated with a variety of medications or medical management. There is still no cure for Alzheimer's, but new treatments - among them donapezil, rivistagamine, and galantamine - are capable of slowing down its progression and can decrease the behavioral problems that accompany certain stages of the disease.

Delirium is an acute state of confusion characterized by agitation and hallucination that occurs when someone is medically ill. Delirium itself is a secondary problem that only complicates the medical condition. Any ailment can be the catalyst.

"It's often brought on by something like a urinary tract infection. Most patients suffering from delirium come into the hospital from nursing homes and we find they have an infection or are dehydrated," says Dr. Sakauye. "Patients with dementia in nursing homes need psychiatric care but aren't getting it because it's seen as unnecessary."

However, the most common of the three "D's" is depression, a "mood disorder" that can be effectively treated with anti-depressants or psychotherapy. According to a recent Surgeon General's report, as many as 20 percent of older adults in the United States and nearly 40 percent of older adults that live in a primary care setting experience symptoms of depression.

"Depression prevalence rates are higher in people with chronic medical conditions and with people in institutional settings," says Dr. Colenda. "Chronic medical conditions increase the risk of having an affective mental disorder. Depression and anxiety commonly go hand-in-hand with medical conditions."

Besides the existence of other medical conditions, there are several other issues to consider when determining the cause of depression. Women with depression outnumber men by a 2 to 1 ratio. Experts offer several reasons for this disproportion, including psychological, social, biological and even emotional factors. Some even accredit it to the fact that statistically women live longer than men.

"Depression is the most common because it is tied in with chronic physical illness," says Dr. Josepha Cheong, associate chair for education at University of Florida's Department of Psychiatry and chief of geriatric psychiatry at the College of Medicine. "But just because someone has cancer or heart disease doesn't mean depression is a normal state - just that it is more likely to develop."

Unfortunately, depression is easy for the time-pressed family physician to miss during a routine examination because the elderly are adept at masking it with "culturally acceptable" complaints such as headaches, backache, and nausea.

"You have to talk to people before you realize how depressed they are," says Dr. Sakauye. "We have the medical equivalent of 'don't ask, don't tell.' All health professionals are qualified to screen for depression and should know if it's severe enough to refer. That's not being done very often."

Depression itself can be treated. Untreated, however, depression can lead to disability, worsen symptoms of other illnesses, lead to premature death and result in suicide. The elderly have the highest rate of suicide in the country and the risk of suicide increases with age.

There are also deterrents to be found within our own national health care system, which makes seniors have to pay more when being treated for a mental illness than when they would be treated for physical ailments.

Current Medicare law imposes a 50 percent co-payment requirement on outpatient psychiatric services, in contrast to the 20 percent out-of-pocket co-payment seniors pay for outpatient medical care. The American Psychiatric Association calls the 50 percent co-payment "blatantly discriminatory" and supports legislation that would provide parity for physical and mental treatments.

How can the family determine when it's time to step in because a loved one appears to be suffering from mental illness and needs treatment?

The first step, of course, is to be aware and look for the signs. "When it actually affects a person's ability to fully function on a daily basis - that's when you think about treatment," Dr. Cheong says.

For more information, please visit the American Psychiatric Association website at www.pysch.org.