Cancer mortality in patients with schizophrenia: systematic review and meta-analysis

Background Previous studies have reported conflicting results on the association between schizophrenia and cancer mortality. Aims To summarise available evidence and quantify the association between schizophrenia and cancer mortality using meta-analysis. Method We systematically searched literature in the PubMed and Embase databases. Risk estimates and 95% confidence intervals reported in individual studies were pooled using the DerSimonian-Laird random-effects model. Results We included 19 studies in the meta-analysis. Among them, 15 studies reported standardised mortality ratios (SMRs) comparing patients with schizophrenia with the general population, and the pooled SMR was 1.40 (95% Cl 1.29-1.52, P < 0.001). The other four studies reported hazard ratios (HRs) comparing individuals with schizophrenia with those without schizophrenia; the pooled HR was 1.51 (95% Cl 1.13-2.03, P = 0.006). Conclusions Patients with schizophrenia are at a significantly increased risk of cancer mortality compared with the general population or individuals without schizophrenia.