Cancer incidence and mortality following exposures to distal and proximal major stressors

Purpose: Severe psychological trauma has been shown to leave psychological and biological sequelae, including compromise of the neuro-hormonal and immunological systems. Despite much research, the putative effect of such stressor on cancer remains ambiguous. This study maximized the exploration of cancer incidence and mortality by combining a proximal (parental bereavement) with a distal major stressor (Holocaust exposure) on both risks. Methods: Subjects were bereaved Holocaust survivors (n = 904) and comparison individuals (n = 933) selected from the total cohort of 6,284 Jewish-Israeli parents who lost an adult son in war or from non-self-inflicted external causes. Cox regression was used to examine the differential risk for cancer between the two bereaved samples, adjusting for potential confounders. Results: No difference in cancer incidence or mortality was observed between both groups of bereaved parents. However, prior to bereavement, Holocaust survivors had an increased cancer risk compared with their counterparts in the general population. Conclusions: Individuals who faced both a proximal (bereavement) and distal (Holocaust) major stressors had no additive risk for cancer incidence and mortality.