Why are many elderly people forgetful? It may be the blues.
April 17, 2000 (Berkeley, Calif.) -- For years, Maria Cusenza's three children didn't worry much about her. Through her 60s and early 70s, Cusenza was a busy woman living in her own apartment in San Francisco. But in recent years the situation has changed. Cusenza, now 80, has marked memory loss. By afternoon, she forgets a conversation she had that morning. During the week she forgets a weekend outing.
"We have to check on her more often, to make sure she is healthy and safe," says Dorothy Cusenza, 57, one of Maria's two daughters. For the first time Cusenza and her family are talking about home helpers, retirement homes, or having Mom move in with one of her kids. As her forgetfulness increases, she sinks farther and farther into depression.
"Could you be depressed and not know it?" This sounds like a ridiculous question. After all, wouldn't you know if you were depressed? Possibly not. Depression can take hold gradually, without a person realizing that depressive thoughts and feelings are increasingly dominating her perspective - and her life.
Many people assume that depression is easily identifiable, manifesting itself as persistent sadness that doesn't lift. In fact, symptoms of depression can take a variety of forms. Chances are...
Doctors are still trying to determine why Cusenza's memory is fading; they say there's little they can do. But her family wonders if her depression might be causing her memory problems rather than the other way around.
They are intrigued by new research showing that stress and depression may cause some forms of memory loss. The research is important because it suggests that not all memory loss is an inevitable part of aging. '"If you look at a patient as having irreversible dementia, you won't do anything," says Sonia Lupien, PhD, a neuroscientist at Douglas Hospital in Montreal. "If you treat the depression, you can stop the increase of cortisol and prevent the memory loss."
Studies show that prolonged depression or stress leads to elevated levels of cortisol, a "stress" hormone produced by the adrenal glands. This in turn appears to shrink or atrophy the hippocampus, the sea-horse shaped part of the brain associated with many kinds of memory and learning.
"The hippocampus is an organ of the brain that is particularly vulnerable to stress and stress hormones," says Bruce McEwen, the head of neuroendocrinology at Rockefeller University in New York.
While cortisol levels normally fluctuate over the course of a day and night, they often soar when a person is faced with a stressful situation, such as a job interview or a school test. Studies have shown that this affects memory. For example, researchers reported in the April 2000 issue of Nature Neuroscience that people taking cortisone pills (which metabolizes to cortisol in the body) were not as good at remembering a list of words as people taking placebo pills.