Risks factors and outcomes for isolated catheter-related deep venous thrombosis in patients undergoing allogeneic hematopoietic stem cell transplantation

Introduction: Patients undergoing allogenic hematopoietic stem cell transplantation (allo-HSCT) require indwelling central venous catheters. The comparative incidence, risk, and outcome of isolated catheter-related deep venous thrombosis (CR-DVT) versus pulmonary embolism/lower-extremity DVT (PE/LE-DVT) remains unclear. Materials and methods: We conducted a retrospective cohort study for patients undergoing allo-HSCT from 2006 to 2019. CR-DVT and PE/LE-DVT outcomes were screened using ICD codes and radiology reports and confirmed by medical record reviews. Cox regression models were used to assess the association between thrombotic outcomes and pertinent baseline and time-varying covariates. The impact of thrombotic events within 1-year post-transplant (time-varying) on overall mortality was also assessed. Results: Among 2879 patients, the cumulative incidence of isolated CR-DVT and PE/LE-DVT at 12 months was 4.2 % and 4.8 %, respectively. The strongest time-varying predictor for onset of CR-DVT and PE/LE-DVT was hospitalization inpatient status (HR 3.71 [95 % CI 2.16–6.37] and 3.99 [95 % CI 2.00–7.99], respectively). Other overlapping variables included lymphoma diagnosis and BMI > 35 kg/m², whereas acute GVHD grades 2–4 were found to be significantly associated with risk of PE/LE-DVT but not CR-DVT. After adjusting for baseline variables and acute GVHD, the occurrences of CR-DVT and PE/LE-DVT were both independently associated with increased overall mortality (HR 1.58 [95 % CI 1.23–2.02] and HR 1.53 [95 % CI 1.19–1.97], respectively). Conclusions: We observed a high incidence of both CR-DVT and PE/LE-DVT with overlapping and unique risk factors. CR-DVT was also associated with increased mortality similar to PE/LE-DVT. Standardized strategies targeting high-risk hospitalization periods may help mitigate the development of thrombotic outcomes post-transplant.