Risk of venous thromboembolism in children and adolescents with inflammatory bowel disease: A systematic review and meta-analysis

BACKGROUND: A two- to three-fold increased risk of venous thrombotic events (VTE) has been demonstrated in patients with inflammatory bowel disease (IBD) compared to the general population, but less is known about the risk of VTE in child- and pediatric-onset IBD. In recent years, several studies have reported the rising incidence rate of VTE in juvenile patients with IBD, and the related risk factors have been explored. AIM: To evaluate the risk of VTE in children and adolescents with IBD. METHODS: Articles published up to April 2021 were retrieved from PubMed, Embase, Cochrane Library, Web of Science, SinoMed, CNKI, and WANFANG. Data from observational studies and clinical work were extracted. The outcome was the occurrence of VTE according to the type of IBD. The available odds ratio (OR) and the corresponding 95% confidence interval (CI) were extracted to compare the outcomes. Effect size (P), odds ratio (OR), and 95%CI were used to assess the association between VTE risk and IBD disease. Subgroup analyses stratified by subtypes of VTE and IBD were performed. RESULTS: Twelve studies (7450272 IBD patients) were included in the meta-analysis. Child and adolescent IBD patients showed increased VTE risk (P = 0.02, 95%CI: 0.01-0.03). Subgroup analyses stratified by IBD (ulcerative colitis (UC): P = 0.05, 95%CI: 0.03-0.06; Crohn’s disease (CD): P = 0.02, 95%CI: 0.00-0.04) and VTE subtypes (portal vein thrombosis: P = 0.04, 95%CI: 0.02-0.06; deep vein thrombosis: P = 0.03, 95%CI: 0.01-0.05; central venous catheter-related thrombosis: P = 0.23, 95%CI: 0.00-0.46; thromboembolic events: P = 0.02, 95%CI: 0.01-0.03) revealed a significant correlation between VTE risk and IBD. Patients with IBD were more susceptible to VTE risk than those without IBD (OR = 2.99, 95%CI: 1.45-6.18). The funnel plot was asymmetric, suggesting the presence of significant publication bias. Pediatric and adolescent IBD patients have an increased VTE risk. UC and CD patients exhibited a high risk of VTE. The risk of VTE subtypes was increased in IBD patients. CONCLUSION: The current meta-analysis showed that the incidence and risk of VTE are significantly increased in pediatric and adolescent IBD patients. Thus, IBD might be a risk factor for VTE in children and young adults. High-quality prospective cohort studies are necessary to confirm these findings.