Proportion and risk factors for hospital-acquired venous thromboembolism in children: a systematic review and meta-analysis of data from 20 million individuals in 22 countries.

Background: Hospital-acquired venous thromboembolism (HA-VTE) in children has been widely regarded.

Objectives: We aimed to analyze the proportion and risk factors for HA-VTE in hospitalized children.

Methods: We conducted a comprehensive systematic search across 4 databases from 1990 to 2023. Cochran Q test was used to evaluate the heterogeneity of the effect sizes of study, and I statistic was used to quantify the heterogeneity. Pooled estimates were calculated by the inverse-variance weighted method in a fixed-effect model or a random-effect model when heterogeneity was low (I < 25%) or high (I > 25%), respectively.

Results: In total, 105 original papers and 20,718,294 patients were included in the study, and the proportion of HA-VTE in children was 4.1% (95% CI, 2.9%-5.2%). Although the proportion of venous thromboembolism increased over the various research periods, the differences were not statistically significant. In the subgroup analysis based on country, the proportion of pediatric HA-VTE was lowest in the United Kingdom and highest in Spain, whereas when based on region, the proportion was lowest in Asia and highest in North America. Multiple HA-VTE risk factors were identified, including central venous catheter use, age of >10 years, surgery, injury, infection, obesity, mechanical ventilation, blood transfusion, malignancy, coagulation and hemorrhagic disorders, and length of hospital stay.

Conclusion: In this study, we systematically analyzed the proportion and risk factors of HA-VTE in hospitalized children. Our findings provide valuable insights for the prevention and treatment of HA-VTE in pediatric patients.