Higher sense of purpose in life may be linked to lower mortality risk, study finds

Now, a new study led by a Boston University School of Public Health (BUSPH) researcher found that people with higher levels of purpose may have a lower risk of death from any cause, and that this association is applicable across race/ethnicity and gender.

Published in the journal Preventive Medicine, the study results did suggest that this association is slightly stronger among women than it is among men, but there was no significant difference by race/ethnicity.

"Having a purpose in life has been known to improve many health outcomes on average," says study lead author Dr. Koichiro Shiba, assistant professor of epidemiology at BUSPH. "In another study I led, we found that the effect of purpose on lowering all-cause mortality may differ by socioeconomic status. In this study, we extended the prior evidence and found that the beneficial effect of purpose persisted regardless of gender and race/ethnicity."

For the study, Dr. Shiba and colleagues at Harvard T.H. Chan School of Public Health (Harvard Chan) utilized data from the Health and Retirement Study, a nationally representative study of US adults ages 50 and older. The team assessed self-reported sense of purpose among more than 13,000 people, based on the "purpose in life" of the Ryff Psychological Well-being Scales, a widely used tool that measures different aspects of well-being and happiness. The researchers also examined mortality risk over an eight-year period beginning between 2006-2008.

The results showed that people with the highest sense of purpose indicated the lowest risk of death (15.2 percent mortality risk), compared to people with the lowest sense of purpose (36.5 percent mortality risk).

The team also gathered data on additional factors that can influence health, such socioeconomic status, other demographic characteristics, baseline physical health, and depression, and found that an increase in these factors was also associated with increases in a higher sense of purpose.

Dr. Shiba speculates that the stronger observed purpose-mortality association in women may be attributable to gender difference in the use of healthcare services, "one of the postulated pathways linking purpose and health," he says. "Evidence suggests men tend to underuse necessary healthcare services, due to social norm. However, future study investigating the mechanisms underlying the gender difference is warranted."

These findings can help inform future policies and other efforts to improve health and well-being.

"This evidence on effect heterogeneity tells us whether population-level purpose interventions can promote people's health not only on average, but also in an equitable manner," Dr. Shiba says. "Although evidence suggests purpose interventions would not lead to widening racial disparities in mortality, policymakers should also be aware of other sources of heterogeneity, such as SES and gender. Even though people may view purpose as a 'psychological' factor, its impacts on health cannot be explained solely by processes that operate in our mind and biology. We need to consider how the psychological factor interacts with our social world and ultimately impacts our health."

The senior author of the study was Dr. Eric Kim, a research scientist at Harvard Chan at the time of the study. The study was also co-authored by Dr. Laura Kubzansky, professor of social and behavioral sciences at Harvard Chan; David Williams, Florence Sprague Norman and Laura Smart Norman Professor of Public Health and chair of the Department of Social and Behavioral Sciences at Harvard Chan; and Dr. Tyler VanderWeele, John L. Loeb and Frances Lehman Loeb Professor of Epidemiology at Harvard Chan.