Mental lapses linked to depression in middle-aged and older adults
When an older person forgets how to cook a meal or balance a checkbook, or becomes lost on familiar driving routes, the person’s family members may blame normal aging for these problems, or chalk them up to the possible onset of Alzheimer’s disease or another form of dementia.However, depression may be the culprit instead, says a University of North Texas psychologist. Dr. Charles Guarnaccia, associate professor of psychology, says depression is often not diagnosed and treated in older Americans because older Americans are less likely to cry and seem depressed than younger people.“Younger people also lose interest in things that formerly gave them pleasure,” he says. “In older people, depression has an impact on cognitive functioning.”The National Institute of Mental Health estimates than more than 15 percent of older Americans experience depression at some point, while an additional 25 percent have periods of persistent sadness that last two weeks or longer.Guarnaccia and Lauren Innes, a UNT doctoral student in clinical psychology, examined data from the National Institute on Aging’s Health and Retirement Study, a national survey. They wished to determine if depression plays a role in both activities of daily living (ADLs) and instrumental activities of daily living (IADLs) in people ages 50 to 62.Guarnaccia explains that ADLs are defined in the study as simple physical activities such as walking, climbing stairs and bathing and dressing, while IADLs include activities with a greater cognitive component, such as balancing a checkbook or cooking a meal.“This age group is considered to be more middle-aged than elderly. However, we wanted to find if depression is linked to cognitive functioning at those ages before we studied an older population,” he says.The researchers examined data from 2,578 men and 2,446 women with a mean age of 55.8 years. Levels of depression in the group were measured with the Center for Epidemiological Study’s Depression Scale. The study participants also completed a test to recall certain words to measure their cognitive functioning, reported on their abilities to perform activities with a cognitive component to measure IADLs, and answered questions about their abilities to perform physical activities to measure their level of ADLs. Both men and women with higher levels of depression showed greater declines in ADLs and IADLs than men and women with lower levels of depression, Guarnaccia says.In addition, women showed higher levels of depression than men. Guarnaccia believes lack of spousal support may have contributed to this finding.“The study included individuals with spouses as well as those without, and 69 percent of those without spouses were women,” he says. “On average, married individuals tend to experience less depression than single individuals. It’s healthier to be married than to not be married.”Guarnaccia now plans to examine similar data in a related study for men and women ages 75 and older.“It seems likely that more people in this age group with high levels of depression would exhibit the same cognitive and physical problems than the middle-aged group did,” he says.He points out that identifying cognitive problems and physical mobility problems as possible symptoms of depression in older people is important because older people usually don’t seek treatment for depression on their own.“When those who are now elderly were young adults, mental health problems were thought to be shameful, and those with mental health problems were institutionalized,” Guarnaccia says. “That was before anti-psychotic medicines were developed and federal legislation passed to mandate mental health treatment in the least restricted environment possible.”He adds that conditions other than Alzheimer’s disease and other forms of dementia can also lead to impaired cognitive functioning in older Americans, further leading to depression being ignored as the cause of these problems.“Older people may take more than one medication for physical problems, and because medication stays in older people’s systems longer than in younger people, there’s a greater likelihood of the medications interacting with each other and causing cognitive problems. It’s known as pseudodementia,” he says.Guarnaccia presented his research at the annual meeting of the American Psychological Association this summer.