Young adults who either have hostile attitudes or problems coping with stress may be at an increased risk for experiencing memory and thinking problems in middle age, according to research published in Neurology.
“We may not think of our personality traits as having any bearing on how well we think or remember things, but we found that the effect of having a hostile attitude and poor coping skills on thinking ability was similar to the effect of more than a decade of aging,” Lenore J. Launer, PhD, of the National Institutes of Health in Bethesda, Maryland, and a member of the American Academy of Neurology, said in a statement.
To examine the relationship between the two factors, the researchers recruited 3126 black and white men and women born between 1955 and 1968 from the Coronary Artery Risk Development in Young Adults Study (CARDIA).
The researchers assessed the participants’ levels of hostility, levels of stress, and cognitive ability at baseline (mean age 25 years).
To measure hostility, the questionnaires assessed aggressive behavior, a lack of trust for others, and negative feelings associated with social relationships. Another question also measured “effortful coping,” defined as actively trying to reduce stress despite repeated barriers to success.
Based on the participants’ levels of hostility and stress, the researchers divided them into 4 groups for each trait, ranging from the lowest quartiles of hostility or stress to the highest: group 1 for low, group 2 for mid-low, group 3 for mid-high, and group 4 for high.
The researchers found that for both hostility and effortful coping, participants with the highest levels of both traits performed significantly worse on thinking and memory tests 25 years later compared with people who had the lowest levels of hostility and stress.
For example, in a cognitive test examining how well participants could recall a list of 15 words, “those in the fourth compared to those in the first quartile of hostility and effortful coping, respectively, recalled [an average of] 0.16 and 0.30 fewer words (i.e., RAVLT) (P=0.05), substituted correctly 1.88 and 2.33 fewer symbols (i.e., DSST) (P= 0.05), and had 0.57 and 0.38 higher interference score (i.e., Stroop Test) (P= 0.07).
These results remained when the researchers adjusted for depression, negative life events, and discrimination, but when they adjusted for diabetes and high blood pressure, the relationship between hostility and cognitive function was reduced.
The researchers also noted that while low hostility level was associated with higher cognitive functioning scores in midlife, those who had a moderate level of effortful coping (group 3) had higher midlife cognitive function; however, this association was progressively attenuated after adjusting for health and socioeducational characteristics.
“This seems plausible because moderate effortful coping can improve the response to challenges and demanding situations, which may be associated with healthier lifestyles and higher educational and professional achievements that in turn would benefit cognition,” the researchers wrote.
Dr Launer noted that this study is observational, and while it does show an association between levels of hostility and stress in young adults and reduced memory in midlife, it does not prove causality.
“If this link is found in other studies, it will be important to understand whether these personality traits are amenable to changes [that promote] positive social interactions and coping skills, to see if they could play a role in reducing people’s risk for memory and thinking problems in middle age,” she said.