Sports participation in chronic immune thrombocytopenia: Safer than you thought?

Background/objectives: Pediatric patients with chronic immune thrombocytopenia (ITP) commonly have activity limitations placed to prevent injury without data guiding clinical decision-making. The objective of this study was to determine risk factors associated with injury in children with chronic ITP. Design/methods: Retrospective single-center cohort study from January 1, 2008 to March 31, 2019 in subjects age 5-21 years with chronic ITP (platelet count < 100,000/mu L for >1 year). Results: One-hundred-two subjects were included, with a mean diagnosis age of 9.3 +/- 4.6 years. Mean follow-up 3.8 +/- 2.3 years; 61% (62) of subjects were female; 60% (61) participated in organized sports, mean 2 +/- 1 sports/subject; 8.8% (9) received ITP therapy for sports participation. Common sports: basketball (28%) and soccer (28%). There were 31 injuries in 26 subjects, and 68% (21) occurred while at play. Most common injuries: 68% (21/31) soft tissue and 23% (7/31) head trauma. Fifteen (48%) injuries were severe enough for medical evaluation at the time of injury. Only one patient received acute ITP treatment for their injury. Injury was associated with participation in high-risk sports (p<.001), male sex (p=.007), and participation in multiple organized sports (p =.008). Conclusion: In this study of 102 pediatric subjects with chronic ITP, injury was mild and infrequent predominantly occurring while at play. The majority participated in organized sports safely. Risk of injury was associated with high-risk sport participation (p <.001). Only one injury necessitated ITP treatment, suggesting that participation in most sports is likely safe in children with chronic ITP.