An analysis of Health and Retirement Study data found that higher levels of optimism were associated with a slightly lower risk of developing dementia over a study period of up to 14 years. This association remained even after the study authors took into account health behaviors, adjusted for possible reverse causality (the possibility that optimism is lower in the early stages of dementia), and excluded individuals with the poorest mental health. The paper was published in. Journal of the American Geriatrics Society.
Optimism is the general tendency to expect favorable outcomes and believe that difficulties can be managed or overcome. It involves positive expectations for the future, rather than just feeling positive about the present.
Research shows that optimistic people are more likely to use positive coping strategies, persevere toward goals, and seek help when needed. Higher levels of optimism are associated with better psychological well-being and lower perceived levels of depression, anxiety, and stress. It is also associated with healthier behaviors, such as increased physical activity, eating better, and following medical advice.
Some studies have linked optimism to improved cardiovascular health, stronger immune function, and lower risk of premature death. These health benefits may be due, in part, to the fact that optimistic people cope with stress more effectively and maintain stronger social relationships. However, optimism does not guarantee good health, and many associations may also reflect differences in personality, socio-economic status, or pre-existing health conditions.
Söde Stenlund, a researcher at Harvard University’s T.H. Chan School of Public Health, and colleagues noted that a number of previous studies, including some longitudinal studies, have already linked high optimism to improved cognitive health. However, they noted that these studies typically had relatively short follow-up periods, and the possibility of reverse causality between optimism and cognitive health was not fully accounted for.
Researchers analyzed data from the Health and Retirement Study with the aim of investigating the long-term association between optimism and the risk of developing dementia. The Health and Retirement Study is an ongoing, nationally representative cohort study in the United States that began in 1992 and has followed men and women aged 50 and older through biennial in-person interviews, phone calls, and mailed surveys.
For this analysis, the study authors used data from participants who completed cognitive assessments and provided data in face-to-face or telephone interviews who were over 70 years old. This information was needed for the dementia assessment algorithm, which determines whether a participant has dementia. Optimism was measured by self-report with the Life Orientation Test Revised Scale.
In total, data from 9,071 people who did not have dementia at study entry were used in the analysis. Their average age at the time was 74 years old. They were followed for an average of 6.7 years and up to 14 years. Approximately 57% of participants were women.
They found that 3,027 participants developed dementia during the study period. Participants who were more optimistic were less likely to develop dementia. More specifically, after accounting for age, gender, race/ethnicity, education, chronic health conditions, and likelihood of depression, each one standard deviation increase in optimism was associated with a 15% lower risk of developing dementia over the study period.
Interestingly, adding health behaviors (such as physical activity and smoking) did not qualitatively change the results. This finding held true even when the study authors adjusted for possible reverse causation by excluding individuals who developed dementia within the first two years of follow-up.
The study authors concluded that “higher optimism was associated with lower incidence of dementia.” “These findings suggest the potential value of optimism in supporting healthy aging and may be considered in future research on dementia prevention efforts.”
This study contributes to scientific knowledge about dementia risk and protective factors. However, the study authors note that many potentially eligible participants were excluded from the analysis due to missing data. These people tended to be younger, more likely to be non-Hispanic white, have some higher education, and generally be healthier. This may have some impact on the generalizability of the findings. Because this study is observational, there remains the possibility of unmeasured confounding variables.
The paper, “The Bright Side of Life: Optimism and Dementia Risk,” was authored by Säde Stenlund, Hayami K. Koga, Peter James, Justin Farmer, Colleen B. McGrath, Francine Grodstein, and Laura D. Kubzansky.
