Rates of Non-Catheter-Related Venous Thromboembolism Events in Cystic Fibrosis Patients During Hospitalization

Background: Incidence of venous thromboembolism (VTE) is increased in patients with cystic fibrosis (CF), especially with use of central venous catheters. However, the risk of non-catheter related thrombosis (non-CRT) remains poorly defined in hospitalized adult patients with CF. Our primary objective was to determine the rate of non-CRT in CF patients hospitalized with acute bronchiectasis exacerbations.Methods: We reviewed all admissions of adult CF patients to the pulmonary ward at the University of Alberta Hospital for respiratory exacerbations between 2006-2016. Comparator group of non-CF patients admitted to the unit with exacerbations of other lung diseases was identified. The primary outcome was the prevalence of non-CRT. Secondary outcomes included incidence and prevalence rates of all VTE, and CF-related risk factors of VTE.Results: 109 cystic fibrosis patients with 399 admissions, and 315 comparator patients with 353 admissions were identified. There were 6 (1.5%) and 12 (3.4%) thrombotic events in the CF and non-CF cohorts. Overall incidence of VTE was 9 and 27 in 10,000 person days of admission for the CF and non-CF cohorts. Incidence of non-catheter related VTE was 1.5 and 22.8 in 10,000 person days of admission for the CF and non-CF cohorts. The comparator group had higher prevalence of thrombotic risk factors. Prophylactic anticoagulation rates during hospitalization for CF and non-CF group were 67.8% and 75.7%. Analyses of potential thrombotic risk factors among CF patients suggest no correlation to number of exacerbations or duration of stay.Conclusions: The prevalence of VTE in hospitalized adult patients with CF is clinically similar to that reported in the general medical inpatient population, with the risk of non-CRT significantly lower. Larger prospective studies are needed to better determine thrombosis risk during hospitalization for adults with cystic fibrosis.