Social and Psychological Factors in Cancer and Longevity

Abstract

Health behaviors are frequently considered as risk factors for cancer and other diseases that contribute to premature mortality. Despite this consideration, the prevalence of many deleterious behaviors has remained constant or even increased over recent decades. This lack of success in modifying behavior may be due to focus on the individual, and a failure to consider social context and psychological states that pattern and influence the performance of behavior. To fully understand risk factors for cancer and premature mortality it is necessary to look further upstream from behaviors and consider psychosocial risk factors and assets, as well as the pathways through which they are associated with health. The studies in this dissertation used data from the Nurses’ Health Study to evaluate relationships that link the social environment to mortality and cancer incidence via pathways including adaptive resources, adverse psychosocial exposures, and health behaviors. Study 1 found that participants with higher levels of depressive symptoms had a greater risk of lung cancer compared to those with lower levels of depressive symptoms. In a test of mediation by smoking history, lifetime pack-years of smoking accounted for approximately half of the observed relationship. Study 2 revealed that childhood socioeconomic status, operationalized as parental occupation, was associated with patterns of health behavior and colon cancer risk in later life. Compared to participants with white collar parents, participants with blue collar parents were at greater risk of adopting an unhealthy lifestyle in adulthood. Additionally, participants with blue collar parents had a slightly elevated, but not statistically significant, increased risk of colon cancer compared to participants with white collar parents. Study 3 demonstrated that higher levels of social integration were associated with longer lifespan and a greater likelihood of achieving exceptional longevity. This association was slightly attenuated but remained statistically significant after controlling for health behaviors. In conclusion, this dissertation demonstrates the role that social and psychological factors play in cancer risk and longevity. By examining these fundamental determinants of health, this line of research may facilitate identification of targets for effective intervention that go beyond traditional attempts to modify single proximal risk factors for disease.