Abstract
INTRODUCTION: Siblings of children with cancer may be vulnerable to compromised long-term health. We aimed to describe the frequency (prevalence, incidence) of adverse physical health outcomes and healthcare service utilization among siblings of children with cancer and compare the risk of the above outcomes to siblings of children without cancer. METHODS: We searched Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, CINAHL, and Clarivate Web of Science through June 15, 2024. We included English and French-language studies, both with and without a healthy control population, that reported adverse physical health outcomes and/or healthcare service utilization outcomes among siblings of children with cancer. Studies focusing exclusively on mental health or quality of life were excluded. Abstracts were screened by two reviewers; full-text articles underwent data abstraction and risk of bias assessment. Results were synthesized descriptively. RESULTS: Of 26,570 studies screened, 44 were included. Heterogeneity was observed in all reported outcomes: mortality; cancer; organ system disease; overweight/obesity; pain; congenital anomalies; comorbidities; infections; amputations; adverse health behavior (smoking, alcohol consumption); infertility; healthcare service utilization (hospitalization, emergency department/urgent care visits, prescriptions). We detected a trend toward increased risk of cancer, hospitalizations, and prescription medication use compared to control siblings. Significant study heterogeneity rendered meta-analyses inappropriate. CONCLUSIONS: Siblings of children with cancer are likely vulnerable to various adverse health outcomes. However, the published literature is widely heterogeneous regarding study design, populations, and outcomes measurements, limiting our comprehensive analysis of risk. Future research with homogenized methodology is needed to better quantify risk, which would inform targeted surveillance guidelines and interventions.