Incidence of cancer and stage at diagnosis among people with recent-onset psychotic disorders
Abstract
Evidence on cancer incidence in people with psychotic disorders, compared to the general population, is equivocal, although those with psychotic disorders so have more advanced stage of cancer at the time of diagnosis. The objective of this thesis was to compare cancer incidence and stage at diagnosis for people with psychotic disorders, relative to the general population. Our systematic review did not observe a significant difference in overall cancer incidence among people diagnosed with psychotic disorders (RR = 1.08, 95% CI: 1.00 to 1.16), however people with psychotic disorders were more likely to be present with advanced stage cancer at diagnosis (OR = 1.22, 95% CI: 1.02 to 1.46). Our cohort study found an elevated incidence of cancer in people with non-affective psychotic disorder, relative to the general population (IRR = 1.09, 95%CI: 1.05 to 1.12). Significant heterogeneity was found by cancer site. We found significant effect modification by sex, which was removed when we excluded prostate cancer. Additionally, we identified higher odds of more advanced stage at diagnosis in people with psychotic disorders (OR = 1.23, 95% CI: 1.13, 1.34). These findings are indicative of a significant diagnostic delay and a need to increase education and targeted access to care. Future research should examine the confounding effects of lifestyle factors and anti-psychotic medication, as well as potentially intermediary effects of cardiometabolic disorders.