Association between stress, depression or anxiety and cancer: Rapid review of reviews

Background: Several studies have suggested links between psychological stress, depression or anxiety, and cancer incidence or outcomes. Existing systematic reviews have addressed this question, with differing results.Aims: This rapid systematic umbrella review summarises existing reviews assessing the association between psychological stress, depression or anxiety and cancer incidence or cancer outcomes. Methods: Systematic reviews assessing stress, depression or anxiety and cancer were identified via searches of MEDLINE, PsycInfo and Cochrane Database of Systematic Reviews from 2010 to November 2020.Results: Twelve systematic reviews were included, summarising cohort and case-control studies, most of which adjusted for confounders. Regarding cancer incidence, one large meta-analysis reported a significant association between depression/anxiety and cancer incidence, while another showed a non-significant trend. Two further meta-analyses reported significant associations between stressful life events and cancer incidence. Conversely, two meta-analyses of work stress showed no significant association with cancer incidence. Regarding outcomes among cancer patients, three meta-analyses reported significant associations between depression/anxiety and cancer mortality, while another reported a non-significant trend for depression and cancer recurrence. One metaanalysis reported a significant association between partner bereavement and cancer mortality, while another showed no significant association between work stress and cancer mortality. Conclusions: There is consistent evidence for an association between psychological stress, depression or anxiety and cancer incidence in general populations, and some evidence for an association with mortality in cancer populations. Future research may focus on confirmation of these findings, as well as the role of social support and stress-reducing interventions in buffering against these effects.