Stress resilience and cancer risk: a nationwide cohort study.

BACKGROUND: Stress resilience is recognised as a determinant of both psychiatric and somatic health, but the potential link between stress resilience and cancer development has not been explored.

METHODS: In this nationwide cohort study, we examined the association between stress resilience in adolescence and subsequent cancer risk. We identified a cohort of 284 257 Swedish men, born 1952-1956, who underwent compulsory military enlistment examinations including measures of psychological stress resilience (median age 18 years). The resulting score was categorised as low, moderate and high stress resilience. Individuals diagnosed with cancer during the follow-up time were identified through data linkage to the Swedish Cancer Register.

RESULTS: Lowest stress resilience, compared with the highest, was associated with increased risks of liver (HR: 4.73, 95% CI 2.73 to 8.19) and lung (HR: 2.75, 95% CI 2.02 to 3.74) cancer after adjusting for markers of socioeconomic circumstances in childhood (p for trend <0.001 for both cancer types). Further adjustment for cognitive and physical fitness at conscription assessment had a marginal influence. In contrast, men with low stress resilience had a decreased risk of being diagnosed with prostate cancer (HR: 0.65, 95% CI 0.56 to 0.76) and malignant melanoma (HR: 0.65, 95% CI 0.55 to 0.76).

CONCLUSION: We conclude that adolescent stress resilience, plausibly by influencing behavioural choices and social patterns, constitutes an important determinant of adult cancer occurrence. Increased awareness of long-term consequences in susceptible individuals may help direct future efforts to reduce cancer burden in adults.