Completed Suicide Rate in Patients with Cancer: A Systematic Review and Meta-Analysis

Abstract

Background: Suicide is a significant cause of death and growing evidence attests to the increased risk of suicide among patients with cancer. Rate of completed suicide in cancer patients varied widely in the published literature. We aimed to assess quantify the extent of completed suicide and identify risk factors associated with the suicide rate per 100,000 person-years in cancer patients. Methods: For this systematic review and meta-analysis, we searched PubMed, Web of Science and China National Knowledge Infrastructure (CNKI), reference lists of included studies and additional sources from inception to November 30, 2019, for original research in English or Chinese, reporting suicide rate and the number of completed suicide among cancer patients. Our main outcome was suicide rate per 100,000 person-years with 95% CIs. We investigated heterogeneity in suicide rate estimates using random-effects modelling for the main meta-analyses and planned subgroup and meta-regression. Findings: We identified 37 eligible studies including a total of 41,516 suicides during over 140 million person-years. The pooled estimate suicide rate was 39·66 per 100,000 person-years (95%CI, 33·40-47·10 per 100,000 person-years) with significant between-study heterogeneity (Q = 9795·73, P <0 ·001, I2 = 99·6%, τ2 = 0·27). The suicide rate for cancer patients was higher in men (54·14, 95%CI, 44.66-65·63) than in women (14·12, 95%CI, 11·14-17·90). For both sexes combined, esophagus cancer had the highest rate of suicide (87·71, 95%CI, 27·42-280·54). By sex, suicide rate ranked first in males and females were pancreas cancer (195·70, 95%CI, 129·55-295·61) and lung cancer (19·31, 95%CI, 16·29-22·86), respectively. The highest suicide rate was 61·02(95%CI, 53·66-69·40) in Asia, and Oceania (24, 95%CI, 21-28) had lowest suicide rate. Suicide rate increased by age at diagnosis, which varied from 20·88(95%CI, 15·75-27·69) among cohorts of younger than 39 years old to 49·06(95%CI, 38·57-62·40) among patients older than 80 years old. Suicide rate in cancer patients had a downward trend by years after diagnosis, with the first six months after cancer diagnosis clearly standing out as a highly stressful period (136·28, 95%CI, 57·10-325·27). Importantly, we found a significant association between general population suicide rates and the rates of suicide in patients with cancer (coefficient =1·308071; 95% CI, 0·351-2.265; t=2·81, P=0·009). Interpretation: Our findings demonstrated that suicide rate among patients with cancer was higher than general population despite the declined trend recent years, which emphasized psychological health aspects interventions and serve as a call to action for the urgent need for public health preventive interventions. Funding Statement: Humanities and Social Sciences of Ministry of Education Planning Fund Project Social and People's Livelihood Technology in Nantong city-General Project (MS12019038). Declaration of Interests: The authors declare no competing interests. Ethical Approval Statement: Not required.