B Nemeth1,2, J F Timp1, A van Hylckama Vlieg1, F R Rosendaal1, S C Cannegieter1,3. 1. Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, the Netherlands. 2. Department of Orthopaedic Surgery, Leiden University Medical Center, Leiden, the Netherlands. 3. Department of Thrombosis and Haemostasis, Leiden University Medical Center, Leiden, the Netherlands.
Abstract
Essentials The risk of recurrent venous thrombosis (VT) after leg-cast in patients with prior VT is unknown. In a nested case-control study within the MEGA follow-up study we aimed to estimate this risk. Patients with a history of VT who require lower-leg cast have a 4.5-fold risk for recurrence. This relative risk translates to an absolute risk for recurrent VT of about 3.2% within 3 months. SUMMARY: Background Patients with lower-leg cast immobilization have a substantially increased risk of developing a first venous thrombosis (VT), whereas the risk in patients with a history of VT is as yet unknown. Aims To estimate the risk of recurrent VT after lower-leg cast immobilization in patients with a history of VT. Methods A case-control study nested within a cohort of 4597 patients with a first VT who were followed over time for recurrence from 1999 to 2010 (MEGA follow-up study). Participants completed a questionnaire on risk factors for recurrent thrombosis, including having a cast in the first 3 months before a recurrence (cases) or a random 3-month period during follow-up for participants without recurrence (controls). In total, 2723/4597 (59%) participants returned the questionnaire. Odds ratios (ORs), adjusted for age and sex, were calculated to compare risks of recurrence between subjects with and without a cast. Results A total of 2525/2723 participants (93%) filled out information on cast immobilization and were included in the analysis (451 cases; 2074 controls). Twenty (1.0%) controls and 10 (2.2%) cases reported having had a lower-leg cast in the 3 months before the control or recurrence date (adjusted OR, 2.4; 95% confidence Interval [CI], 1.1-5.3). We cross-checked the data with these patients' medical records. Cast application within 3 months was verified in seven (0.3%) controls vs. six (1.3%) cases, leading to an adjusted OR of 4.5 (95% CI, 1.5-14.0) and corresponding cumulative incidence of 3.2%. Conclusions Lower-leg cast immobilization increases the risk of recurrent VT in the 3 months after its application in patients with a history of VT.
Essentials The risk of recurrent venous thrombosis (VT) after leg-cast in patients with prior VT is unknown. In a nested case-control study within the MEGA follow-up study we aimed to estimate this risk. Patients with a history of VT who require lower-leg cast have a 4.5-fold risk for recurrence. This relative risk translates to an absolute risk for recurrent VT of about 3.2% within 3 months. SUMMARY: Background Patients with lower-leg cast immobilization have a substantially increased risk of developing a first venous thrombosis (VT), whereas the risk in patients with a history of VT is as yet unknown. Aims To estimate the risk of recurrent VT after lower-leg cast immobilization in patients with a history of VT. Methods A case-control study nested within a cohort of 4597 patients with a first VT who were followed over time for recurrence from 1999 to 2010 (MEGA follow-up study). Participants completed a questionnaire on risk factors for recurrent thrombosis, including having a cast in the first 3 months before a recurrence (cases) or a random 3-month period during follow-up for participants without recurrence (controls). In total, 2723/4597 (59%) participants returned the questionnaire. Odds ratios (ORs), adjusted for age and sex, were calculated to compare risks of recurrence between subjects with and without a cast. Results A total of 2525/2723 participants (93%) filled out information on cast immobilization and were included in the analysis (451 cases; 2074 controls). Twenty (1.0%) controls and 10 (2.2%) cases reported having had a lower-leg cast in the 3 months before the control or recurrence date (adjusted OR, 2.4; 95% confidence Interval [CI], 1.1-5.3). We cross-checked the data with these patients' medical records. Cast application within 3 months was verified in seven (0.3%) controls vs. six (1.3%) cases, leading to an adjusted OR of 4.5 (95% CI, 1.5-14.0) and corresponding cumulative incidence of 3.2%. Conclusions Lower-leg cast immobilization increases the risk of recurrent VT in the 3 months after its application in patients with a history of VT.
Authors: Jasmijn F Timp; Sigrid K Braekkan; Willem M Lijfering; Astrid van Hylckama Vlieg; John-Bjarne Hansen; Frits R Rosendaal; Saskia le Cessie; Suzanne C Cannegieter Journal: PLoS Med Date: 2019-10-11 Impact factor: 11.069
Authors: Hannah C Puhr; Lisbeth Eischer; Hana Šinkovec; Ludwig Traby; Paul A Kyrle; Sabine Eichinger Journal: J Thromb Thrombolysis Date: 2020-05 Impact factor: 2.300