Characteristics of upper- and lower-extremity deep vein thrombosis and predictors of postthrombotic syndrome in children.

Our understanding of postthrombotic syndrome (PTS) predictors in children is evolving. The present study aimed to investigate differences in patient- and deep vein thrombosis (DVT)-related characteristics between central venous catheter (CVC)-related and non-CVC-related thrombosis in children, as well as early PTS predictors. Children aged 0 to 18 years were prospectively recruited ≥6 months after imaging-proven upper- or lower-extremity DVT. PTS was measured using CAPTSure. Early predictors included age at DVT diagnosis, DVT symptoms, DVT burden, and days on therapeutic anticoagulation within 30 days post-DVT diagnosis. Analysis of predictors was stratified by CVC-related and non-CVC-related thrombosis. Generalized estimating equations were used for data analyses. In total, 313 DVT-affected extremities of 256 patients were assessed; 275 (88%) DVT cases were CVC related. Patients with non-CVC-related thrombosis were older (median age, 5.8 years; 25th-75th percentile, 4.9-6.4 years vs 3.5 months; 25th-75th percentile, 0.7-18.7 months; P < .001) and more likely to have thrombophilia (64% vs 22%; P < .001) and obesity (30% vs 13%; P = .01) than patients with CVC-related thrombosis. CAPTSure scores were 9.5 points higher (standard error, 3.0; P = .02) in the non-CVC-related thrombosis stratum. Age at the time of DVT predicted PTS in both strata; DVT burden and time from DVT diagnosis to PTS assessment predicted PTS in CVC-related thrombosis. In sum, PTS severity was higher in non-CVC-related vs CVC-related thrombosis. Increasing age at the time of DVT was associated with higher PTS severity. DVT burden and time from DVT diagnosis to PTS assessment were significant PTS predictors in CVC-related thrombosis, indicating that long-term follow-up of these children is important.