STOCKHOLM – People who rely chiefly on interpersonal relationships for support into old age may have a high risk for depression when adverse life events disrupt those relationships, Carolyn Mazure, Ph.D., said at the 12th Congress of the International Psychogeriatric Association.
Researchers have known that younger adults who highly value a need for independence and control appear to have a higher risk for depression after adverse life events than do those who place great importance on interpersonal relationships.
The association between adverse life events and cognitive styles, however, appears to reverse itself in older age, said Dr. Mazure, professor of psychiatry at Yale University, New Haven, Conn.
Dr. Mazure and her colleagues have used the premises of Aaron T. Beck's cognitive theory of depression to predict late-life depression. His theory proposes that life events influence mood based on the meaning that an individual assigns to the life events and suggests that people use certain cognitive styles, or characteristic ways of looking at themselves in the world, to form stable belief systems that influence their interpretation of events.
The two cognitive styles that are inherent to the cognitive theory of depression are sociotropy and autonomy. Sociotropy is characterized by a high investment in interpersonal relationships, a desire to please others to avoid disapproval in order to secure attachments and build relationships, and a fear of separation and abandonment, she said
Autonomy focuses on a need for independence, control, and personal freedom to reduce the possibility of failure.
“If someone's cognitive style is particularly sociotropic, they are going to be more vulnerable to an adverse event that is interpersonal in nature, such as loss of a loved one.” Autonomous individuals, on the other hand, “are going to be more vulnerable to negative achievement events like a change in long-term residence,” as occurs when an individual is forced to leave his or her home of 40 years to go into an assisted-living facility, she said.
The interaction of sociotropy and autonomy with adverse life events has been studied extensively in U.S. samples of younger individuals, but models that explore the relationship of life stress in the context of cognitive styles generally have not been extended to older adults, she noted.
In one study, Dr. Mazure and her colleagues prospectively matched 42 outpatients who developed major depression at age 60 years or older with 42 nondepressed individuals from the community. Patients with a predominantly sociotropic cognitive style who had an adverse interpersonal life event were 11 times more likely to be diagnosed with depression than were patients without either characteristic. Those who had a predominantly autonomous cognitive style and suffered a negative achievement life event were six times more likely to be diagnosed with depression than were those without either characteristic (Am. J. Geriatr. Psychiatry 2002;10:297–304).
Medical illness and diminished physical functioning were associated with depression, but even in the context of these effects, the interaction between adverse life events and cognitive styles predicted the onset of depression.
The presence of a predominantly sociotropic cognitive style without an adverse life event made an individual three times more likely to be diagnosed with depression. A predominantly autonomous cognitive style without an adverse life event made individuals 55% less likely to be diagnosed with depression than were those without an autonomous cognitive style, which differs from findings in younger populations.
The investigators excluded patients with dementia or those who scored less than 24 on the Mini-Mental State Examination, as well as those with dysthymia, psychosis, or a history of substance abuse. The investigators asked patients about adverse life events that occurred in the 6 months prior to their diagnosis of depression and asked control individuals about life events in the 6 months prior to their interview.
In other studies that Dr. Mazure and her associates have performed using the same methods, they have found that the risk of depression in people with sociotropic cognitive styles stays the same over the course of life, while autonomy imparts a higher risk for depression at younger ages but gradually drops to contribute less risk for depression than does sociotropy in older people. The interaction of autonomy and negative achievement life events on the risk for depression follows the pattern for autonomy alone, but the interaction of sociotropy and adverse interpersonal life events increases the risk for depression as people age.
Questions to Consider
Dr. Mazure identified three areas for future research involving cognitive style and late-life depression:
▸ Can modifying cognitive styles reduce the risk for depression, especially when individuals are confronted with adverse life events?