Suicide After Childhood Cancer

Abstract

TO THE EDITOR: Dr Recklitis et al report suicidal symptoms in a significant number of adult survivors of childhood cancer and identify risk factors associated with these symptoms. Although the authors do not report risk estimates for suicide in this patient population, their results suggest that adult survivors of childhood cancer are at an elevated risk for suicidality, even many years after treatment. Herein, we provide the first report of an increased risk of suicide in a large, population-based cohort of childhood cancer survivors in the United States. We identified 35,814 children diagnosed with cancer before age 21 years between 1973 and 2003 and reported to one of nine registries in the Surveillance, Epidemiology, and End Results program. Previous population-based follow-up studies of patients diagnosed with cancer at all ages taken together found 1.3to 2.9-fold standardized mortality ratios (SMRs) of suicide; however, separate risk estimates for childhood cancer survivors were not provided. Investigations of survivors of childhood cancer have been limited to hospital or clinical series. In our study, 36 childhood cancer survivors committed suicide (SMR 11; 95% CI, 7.8 to 15.3; excess absolute risk (EAR) 10 per 100,000 person-years). The median duration between initial cancer diagnosis and suicide was 10 years (range, 0.7 to 22 years). The median age at suicide was 26.8 years (range, 15.8 to 35.5 years). Significantly elevated SMRs of 11.7, 5.9, 13.8, and 11.7 were observed less than 1 year, 1 to 4 years, 5 to 9 years, and 10 or more years after initial cancer diagnosis, with no evidence of a diminution in risk with time. Risk for patients diagnosed with cancer at ages 10 to 14 years (SMR 12.9; 95% CI, 5.6 to 25.4) and 15 to 20 years (SMR 12.1; 95% CI, 7.7 to 17.9) was higher than those diagnosed at younger ages (0 to 4 years, SMR 3.26; 95% CI, 0.0 to 18.1; 5 to 9 years, SMR 8.8; 95% CI, 1.8 to 25.8). Suicide risk was comparable for males (SMR 10.9; 95% CI, 7.3 to 15.6) and females (SMR 11.8; 95% CI, 4.7 to 24.4). SMRs were similar for patients diagnosed before 1985 (SMR 11.9; 95% CI, 7.8 to 17.5) and those diagnosed in subsequent calendar years (SMR 9.2; 95% CI, 4.4 to 17.0). Risk was not higher for patients initially treated with radiation (SMR 9.8; 95% CI, 5.2 to 16.8) compared with those who did not receive radiotherapy as part of the primary therapy (SMR 11.9; 95% CI, 7.5 to 17.8). Although suicide among childhood cancer survivors is a rare event, the significantly elevated risk in this population-based survey is noteworthy. Our findings are consistent with those observed by Recklitis et al. Survivors of childhood cancer not only report an increased number of suicidal symptoms, but they also are at an increased risk of suicide. These results underscore the importance of incorporating resources devoted to psychosocial concerns into long-term follow-up programs for childhood cancer survivors.