A large US study, following women for 10 years and men for 30 years, found that individuals with greater optimism are more likely to live longer and to achieve “exceptional longevity”, that is, living to age 85 or older. The most optimistic achieved, on average, an 11% to 15% longer lifespan.
Researchers from Boston University School of Medicine (BUSM), National Centre for PTSD at VA Boston Healthcare System and Harvard TH Chan School of Public Health combined in the study.
Optimism refers to a general expectation that good things will happen, or believing that the future will be favourable because we can control important outcomes. Whereas research has identified many risk factors that increase the likelihood of diseases and premature death, much less is known about positive psycho-social factors that can promote healthy ageing.
The study was based on 69,744 women and 1,429 men. Both groups completed survey measures to assess their level of optimism, as well as their overall health and health habits such as diet, smoking and alcohol use. Women were followed for 10 years, while the men were followed for 30 years. When individuals were compared based on their initial levels of optimism, the researchers found that the most optimistic men and women demonstrated, on average, an 11% to 15% longer lifespan, and had 50%-70% greater odds of reaching 85 years old compared to the least optimistic groups. The results were maintained after accounting for age, demographic factors such as educational attainment, chronic diseases, depression and also health behaviours, such as alcohol use, exercise, diet and primary care visits.
“While research has identified many risk factors for diseases and premature death, we know relatively less about positive psycho-social factors that can promote healthy aging,” explained corresponding author Dr Lewina Lee, clinical research psychologist at the National Centre for PTSD at VA Boston and assistant professor of psychiatry at BUSM. “This study has strong public health relevance because it suggests that optimism is one such psycho-social asset that has the potential to extend the human lifespan. Interestingly, optimism may be modifiable using relatively simple techniques or therapies.”
It is unclear how exactly optimism helps people attain longer life. “Other research suggests that more optimistic people may be able to regulate emotions and behaviour as well as bounce back from stressors and difficulties more effectively,” said senior author Dr Laura Kubzansky, Lee Kum Kee professor of social and behavioural sciences and co-director, Lee Kum Sheung Centre for Health and Happiness at the Harvard TH Chan School of Public Health.
The researchers also consider that more optimistic people tend to have healthier habits, such as being more likely to engage in more exercise and less likely to smoke, which could extend lifespan. “Research on the reason why optimism matters so much remains to be done, but the link between optimism and health is becoming more evident,” noted senior author Dr Fran Grodstein, professor of epidemiology at the Harvard TH Chan School of Public Health and professor of medicine at the Channing Division of Network Medicine at Brigham and Women’s Hospital and Harvard Medical School.
“Our study contributes to scientific knowledge on health assets that may protect against mortality risk and promote resilient aging. We hope that our findings will inspire further research on interventions to enhance positive health assets that may improve the public’s health with aging,” added Lee.
Most research on exceptional longevity has investigated biomedical factors associated with survival, but recent work suggests nonbiological factors are also important. Thus, we tested whether higher optimism was associated with longer life span and greater likelihood of exceptional longevity. Data are from 2 cohorts, women from the Nurses’ Health Study (NHS) and men from the Veterans Affairs Normative Aging Study (NAS), with follow-up of 10 y (2004 to 2014) and 30 y (1986 to 2016), respectively. Optimism was assessed using the Life Orientation Test–Revised in NHS and the Revised Optimism–Pessimism Scale from the Minnesota Multiphasic Personality Inventory-2 in NAS. Exceptional longevity was defined as survival to age 85 or older. Primary analyses used accelerated failure time models to assess differences in life span associated with optimism; models adjusted for demographic confounders and health conditions, and subsequently considered the role of health behaviors. Further analyses used logistic regression to evaluate the likelihood of exceptional longevity. In both sexes, we found a dose-dependent association of higher optimism levels at baseline with increased longevity (P trend < 0.01). For example, adjusting for demographics and health conditions, women in the highest versus lowest optimism quartile had 14.9% (95% confidence interval, 11.9 to 18.0) longer life span. Findings were similar in men. Participants with highest versus lowest optimism levels had 1.5 (women) and 1.7 (men) greater odds of surviving to age 85; these relationships were maintained after adjusting for health behaviors. Given work indicating optimism is modifiable, these findings suggest optimism may provide a valuable target to test for strategies to promote longevity.
Lewina O Lee, Peter James, Emily S Zevon, Eric S Kim, Claudia Trudel-Fitzgerald, Avron Spiro III, Francine Grodstein, Laura D Kubzansky