25 mm Hg versus 35 mm Hg elastic compression stockings to prevent post-thrombotic syndrome after deep vein thrombosis (CELEST): a randomised, double-blind, non-inferiority trial.

BACKGROUND: The optimal strength of compression needed to prevent post-thrombotic syndrome (PTS) after a proximal deep vein thrombosis (DVT) is debated. We aimed to assess whether 25 mm Hg elastic compression stockings (ECS) are non-inferior to 35 mm Hg ECS in preventing PTS after a DVT. METHODS: In this multicentre, double-blind, non-inferiority, randomised controlled trial, we enrolled adults (≥18 years) with a first ipsilateral proximal DVT attending 46 French vascular medicine hospital departments or private practices. Participants were randomly allocated (1:1, stratified by centre, age, and sex; with varying block sizes of two and four) to wear 25 mm Hg or 35 mm Hg ECS for 2 years. The primary outcome was the cumulative rate of PTS 2 years after inclusion, defined by a Villalta scale (≥5). Efficacy was assessed by intention-to-treat and in eligible participants who had complete primary outcome data. A per-protocol analysis was also conducted among compliant patients as a secondary outcome measure. Safety was assessed in all participants who used ECS at least once, and for which we have at least some tolerance information during follow-up. The margin for non-inferiority was 12·5%. This study is registered with ClinicalTrials.gov, NCT01578122, and has been completed. FINDINGS: Between June 28, 2012, and July 21, 2017, we enrolled 341 eligible participants who consented to randomisation. 233 (68%) were men and median age was 59 years (IQR 45-70). Collection of ethnicity and race as a routine research variable is not authorised in France. Median follow-up was 735 days (IQR 721-760). 249 (73%) had complete data at 2 years. For the primary analysis, 40 (31%) of 129 participants with complete data in the 25 mm Hg ECS group and 40 (33%) of 120 in the 35 mm Hg group had PTS (absolute difference -2·3% [90% CI -12·1 to 7·4], pnon-inferiority=0·0062; relative risk 0·93, 95% CI 0·65 to 1·33). Results remained similar after imputation of missing data in patients we were authorised to do so: the cumulative proportion of PTS was 45 (29%) of 154 in the 25 mm Hg ECS group versus 52 (35%) of 148 in the 35 mm Hg ECS group (relative risk 0·83, 95% CI 0·60 to 1·16). Absolute difference was -5·9%, (90% CI -14·7 to 2·9), p=0·0003 for non-inferiority. Adherence was optimal (>80% and modified GIRERD score of 0-2) for 75 (51%) of 146 patients assigned to 25 mm Hg ECS and for 56 (42%) of 134 patients assigned to 35 mm Hg ECS (p=0·11). Regarding major adverse events related to ECS, there were no between-group differences in rates of deep vein thrombosis (0 vs 1 [0·6%]), ipsilateral leg ulcer (0 vs 1 [0·6%]), infection (0 vs 0), or death (0 vs 0) between the 169 patients evaluated in the 25 mm Hg ECS group and the 159 patients in the 35 mm Hg ECS group. Two (1%) of 328 patients who ever wore ESC developed ECS-related serious adverse events, one distal DVT and one leg ulcer (both in the 35 mm Hg ECS group). In the 25 mm Hg group, 6 patients died, 14 had a venous thromboembolic recurrence (proximal DVT or pulmonary embolism), and 7 had a major bleed. In the 35 mm Hg group, 5 patients died, 10 had a venous thromboembolic recurrence (proximal DVT or pulmonary embolism), and 6 had a major bleed. INTERPRETATION: Although we did not reach the prespecified sample size, our results suggest that 25 mm Hg ECS are non-inferior to 35 mm Hg ECS in preventing PTS. Larger more powerful studies are needed. FUNDING: Laboratoires Innothera, France.

Long-term risk of postthrombotic syndrome after symptomatic distal deep vein thrombosis: The CACTUS-PTS study.

BACKGROUND: After a proximal lower limb deep vein thrombosis (DVT; involving popliteal veins or above), up to 40% of patients develop postthrombotic syndrome (PTS) as assessed by the Villalta scale (VS). Poor initial anticoagulant treatment is a known risk factor for PTS. The risk of developing PTS after isolated distal DVT (infra-popliteal DVT without pulmonary embolism), and the impact of anticoagulant treatment on this risk, are uncertain. METHODS: Long-term follow-up of CACTUS double-blind trial comparing 6 weeks of s.c. nadroparin (171 IU/kg/d) versus s.c. placebo for a first symptomatic isolated distal DVT. At least 1 year after randomization, patients had a PTS assessment in clinic or by phone using the VS. RESULTS: After a median follow-up of 6 years, PTS was present in 30% (n = 54) of the 178 patients who had a PTS assessment. PTS was moderate or severe in 24% (n = 13) of cases. There was no statistically significant difference in prevalence of PTS in the nadroparin versus placebo groups (29% versus 32%, P = .6), except in patients without evidence of primary chronic venous insufficiency (9% versus 24%, P = .04). Rates of venous thromboembolism recurrence during follow-up in the nadroparin and placebo groups were, respectively, 8% (n = 7) and 14% (n = 13; P = .2). CONCLUSION: After a first isolated distal DVT, the risk of PTS is substantial but much lower than that reported after proximal DVT. Anticoagulation with nadroparin doesn't provide any clear benefit to prevent PTS, except in patients without preexisting chronic venous insufficiency. Anticoagulation might be associated with a lower risk of venous thromboembolism recurrence.

Diagnosis of deep vein thrombosis recurrence: Ultrasound criteria.

INTRODUCTION: Recurrent deep vein thrombosis (DVT) is often suspected in patients after anticoagulant drug withdrawal. The clinical signs can be confused with the onset of post-thrombotic syndrome. For these reasons, diagnosis of DVT recurrence must rely on an accurate method. MATERIALS AND METHODS: In order to assess this challenging clinical issue, we performed an overview of the literature regarding ultrasound criteria for the diagnosis of recurrent DVT through a Medline search, which included articles published from January 1, 1980 to February 20, 2017. RESULTS: Eighty-eight publications were found based on the defined keywords, of which nine articles with a relevant abstract were selected. By searching the reference lists of these nine articles, we obtained another 27 relevant articles. A new non-compressible vein or an increase in the diameter of a previously thrombosed vein segment by >4mm are sufficient to confirm the diagnosis of DVT recurrence. In contrast, an increase in diameter of <2mm enables recurrence to be ruled out. An increase between 2 and 4mm is deemed equivocal. Criteria based on echogenicity and Doppler venous blood flow are not reproducible. Other diagnostic imaging methods, mainly direct thrombus magnetic resonance imaging, are currently under evaluation. CONCLUSIONS: Ultrasound remains the most useful test for the diagnosis of recurrent DVT. Further imaging tests need to be validated.

Anticoagulant therapy for symptomatic calf deep vein thrombosis (CACTUS): a randomised, double-blind, placebo-controlled trial.

BACKGROUND: The efficacy and safety of anticoagulant treatment is not established for patients with acute symptomatic deep vein thrombosis (DVT) of the calf. We aimed to assess whether therapeutic anticoagulation is superior to placebo in patients with symptomatic calf DVT. METHODS: In this randomised, double-blind, placebo-controlled trial, we enrolled low-risk outpatients (without active cancer or previous venous thromboembolic disease) with a first acute symptomatic DVT in the calf from 23 university medical centres or community medical clinics in Canada, France, and Switzerland. We randomly assigned (1:1) patients to receive either the low-molecular-weight heparin nadroparin (171 UI/kg, subcutaneously, once a day) or placebo (saline 0·9%, subcutaneously, once a day) for 6 weeks (42 days). Central randomisation was done using a computer-generated randomisation list, stratified by study centre. Random allocation sequences of variable block size were centrally determined by an independent research clinical centre. Study staff, patients, and outcome assessors (central adjudication committee) were masked to group assignment. Numbered boxes of active drug or placebo were provided to pharmacies in identical packaging. All patients were prescribed compression stockings and followed up for 90 days. The primary efficacy outcome was a composite measure of extension of calf DVT to proximal veins, contralateral proximal DVT, and symptomatic pulmonary embolism at day 42 in the modified intention-to-treat population. The primary safety outcome was major or clinically relevant non-major bleeding at day 42. The trial was registered with ClinicalTrials.gov, number NCT00421538. FINDINGS: Between Feb 1, 2008, and Nov 30, 2014, we screened 746 patients, enrolling 259 patients (50% of the prespecified sample size), before the trial steering committee terminated the trial because of expiry of study drug and slow recruitment. The intention-to-treat analysis population comprised 122 patients in the nadroparin group and 130 in the placebo group. There was no significant difference between the groups in the composite primary outcome, which occurred in four patients (3%) in the nadroparin group and in seven (5%) in the placebo group (risk difference -2·1%, 95% CI -7·8 to 3·5; p=0·54). Bleeding occurred in five patients (4%) in the nadroparin group and no patients in the placebo group (risk difference 4·1, 95% CI 0·4 to 9·2; p=0·0255). In the nadroparin group one patient died from metastatic pancreatic cancer and one patient was diagnosed with heparin-induced thrombocytopenia type 2. INTERPRETATION: Nadroparin was not superior to placebo in reducing the risk of proximal extension or venous thromboembolic events in low-risk outpatients with symptomatic calf DVT, but did increase the risk of bleeding. Avoidance of systematic anticoagulation for calf DVT could have a substantial impact on individual patients and from a public health perspective. FUNDING: Swiss National Science Foundation, the Programme Hospitalier de Recherche Clinique in France, and the Canadian Institutes of Health Research.

Superficial venous thrombosis and compression ultrasound imaging.

BACKGROUND: A current debate concerning suspected superficial vein thrombosis (SVT) focuses on the need of performing a compression ultrasound (CUS) exploration for confirming the diagnosis of SVT. This study was conducted to determine the clinical relevance and optimal CUS exploration in patients with symptomatic SVT. METHODS: We analyzed the characteristics of SVT and concomitant deep vein thrombosis (DVT) in patients included in the Prospective Observational Superficial Thrombophlebitis (POST) multicenter, observational prospective study. All patients underwent complete bilateral lower limb CUS, exploring both the superficial and deep venous systems. RESULTS: A total of 844 patients with clinical symptoms of SVT were recruited, of which 99 isolated SVTs (21.4%) had saphenofemoral/popliteal junction involvement, and 198 (23.5%) had a concomitant DVT, with 41.8% of them proximal DVTs. In 83 patients (41.9%), DVT and SVT were not contiguous. Five of 639 patients (1%) had an isolated contralateral DVT (ie, not bilateral). Age ≥ 75 years (odds ratio [OR], 2.3; 95% confidence interval [CI], 1.6-3.4), inpatient status (OR, 5.4; 95% CI, 3.4-8.7), a personal history of DVT or pulmonary embolism (OR, 1.8; 95% CI, 1.2-2.8), and SVT on nonvaricose veins (OR, 3.3; 95% CI, 2.1-5.0) were significantly and independently associated with an increased risk of concomitant DVT. Half of the patients exhibited none of these risk factors, and the prevalence of concomitant DVT dropped to 11%. CONCLUSIONS: In patients with symptomatic SVT, a CUS exploration screening the whole venous system of the affected limb is useful because it provides information that has important consequences for the management of these patients.

Radio-opaque ethylcellulose-ethanol is a safe and efficient sclerosing agent for venous malformations.

OBJECTIVE: To evaluate the efficacy and safety of gelified ethanol, a newly developed sclerosing agent for slow-flow vascular malformations. METHODS: Seventy-nine sclerotherapy procedures were performed on 44 patients with 37 venous malformations, 2 glomuvenous malformations, 2 lymphatic malformations, 2 lymphatico-venous malformations, and 1 Klippel-Trenaunay syndrome. The median injected volume was 1.00 mL/site of injection. Effects of sclerotherapy on pain, functional and cosmetic disturbance were statistically evaluated with a final result score. Local and systemic complications were recorded. RESULTS: The mean Visual Analogue Scores were 5.20 ± 2.81 before and 1.52 ± 1.25 after treatment (p < 0.001). Functional and aesthetic improvement was achieved in 31/35 patients (89%) and in 33/41 (80%), respectively. Minor local side effects included necrosis with or without issue of ethylcellulose, palpable residue, and hematoma. No systemic side-effects occurred. CONCLUSION: Per mL used, radio-opaque gelified ethanol is at least as effective as absolute ethanol. No systemic complication was observed, as only a low dose of ethanol was injected. Indications for sclerotherapy can be widened to areas with higher risk for local side effects (hands and periocular region), as ethanol is trapped in the lesion. Careful injection procedure is though necessary, because only a limited amount of ethylcellulose can be used per puncture. Key Points • Development of a new sclerosing agent for venous malformations. • Interesting novel way to deliver alcohol to slow-flow vascular malformations. • Alcohol-based with less local and systemic side-effects.

Short versus extended thromboprophylaxis after total knee arthroplasty: a randomized comparison.

INTRODUCTION: The optimal duration of thromboprophylaxis after total knee arthroplasty remains uncertain. MATERIAL AND METHODS: We performed a randomized, open trial to determine whether to stop thromboprophylactic therapy at Day 10±2 ('short thromboprophylaxis') was non-inferior to continue thromboprophylactic therapy up to Day 35±5 ('extended thromboprophylaxis') after total knee arthroplasty. At Day 7±2, subjects were screened by ultrasonography for asymptomatic deep-vein thrombosis and randomized. The primary outcome was a composite of proximal deep-vein thrombosis, any symptomatic deep-vein thrombosis, non-fatal symptomatic pulmonary embolism, major bleeding, heparin-induced thrombocytopenia, or all-cause death up to Day 35±5. The secondary outcome was ultrasonographic (extension or new onset) distal deep-vein thrombosis at Day 35±5. RESULTS: Twenty-one patients (2.4%) were not randomized, because of asymptomatic proximal deep-vein thrombosis on systematic ultrasonography at Day 7±2. Among the 857 randomized patients, mean (SD) duration of anticoagulant treatment was 11.2 (6.7) and 33.9 (3.7) days in the short and extended thromboprophylaxis groups, respectively. The respective rates of the primary outcome were 4.0% (17/420) and 2.4% (10/422), with an absolute difference of 1.7% (90% confidence interval, -0.3 to 3.7). In 285 patients with asymptomatic distal deep-vein thrombosis at Day 7±2, the respective rates of the primary outcome were 7.8% and 2.8% (p=0.067). The rates of the secondary outcome were 14.8% (62/420) and 4.5% (19/422), respectively (p<0.001). CONCLUSIONS: Short thromboprophylaxis was not non-inferior to extended thromboprophylaxis after total knee arthroplasty. In this setting, the thromboembolic risk persisted longer than seven days, notably in patients with asymptomatic distal deep-vein thrombosis at discharge. ClinicalTrials.gov number: NCT00362492.

Superficial venous thrombosis and venous thromboembolism: a large, prospective epidemiologic study.

BACKGROUND: Superficial venous thrombosis (SVT) is perceived to have a benign prognosis. OBJECTIVE: To assess the prevalence of venous thromboembolism in patients with SVT and to determine the 3-month incidence of thromboembolic complications. DESIGN: National cross-sectional and prospective epidemiologic cohort study. (ClinicalTrials.gov registration number: NCT00818688) SETTING: French office- and hospital-based vascular medicine specialists. PATIENTS: 844 consecutive patients with symptomatic SVT of the lower limbs that was at least 5 cm on compression ultrasonography. MEASUREMENTS: Incidence of venous thromboembolism and extension or recurrence of SVT in patients with isolated SVT at presentation. RESULTS: Among 844 patients with SVT at inclusion (median age, 65 years; 547 women), 210 (24.9%) also had deep venous thrombosis (DVT) or symptomatic pulmonary embolism. Among 600 patients without DVT or pulmonary embolism at inclusion who were eligible for 3-month follow-up, 58 (10.2%) developed thromboembolic complications at 3 months (pulmonary embolism, 3 [0.5%]; DVT, 15 [2.8%]; extension of SVT, 18 [3.3%]; and recurrence of SVT, 10 [1.9%]), despite 540 patients (90.5%) having received anticoagulants. Risk factors for complications at 3 months were male sex, history of DVT or pulmonary embolism, previous cancer, and absence of varicose veins. LIMITATION: The findings are from a specialist referral setting, and the study was terminated before the target patient population was reached because of slow recruitment. CONCLUSION: A substantial number of patients with SVT exhibit venous thromboembolism at presentation, and some that do not can develop this complication in the subsequent 3 months. PRIMARY FUNDING SOURCE: GlaxoSmithKline, sanofi-aventis, and the Ministère Francais de la Santé et des Sports (Programme Hospitalier de Recherche Clinique).

Elevated D-dimer level in the differential diagnosis of venous malformations.

OBJECTIVE: To evaluate if elevated D-dimer level is specific for venous malformations (VMs) and thus useful for differential diagnosis, which can be problematic even in specialized interdisciplinary centers. Localized intravascular coagulopathy, characterized by elevated D-dimer levels, has been observed in approximately 40% of patients with VMs. DESIGN: Prospective convenience sample accrued from 2 interdisciplinary sites. SETTING: Two interdisciplinary centers for vascular anomalies in Brussels, Belgium, and Caen, France PARTICIPANTS: The study population comprised 280 patients with clinical data, Doppler ultrasonograms (for 251 patients), and coagulation parameter measurements. Main Outcome Measure Measurement of D-dimer levels. RESULTS: A VM was diagnosed in 195 of 280 patients (69.6%), and 83 of them had elevated D-dimer levels; the sensitivity of D-dimer dosage was 42.6% (95% confidence interval, 35.6%-49.5%). Among the 85 patients without VM, D-dimer levels were elevated only in 3 patients; the specificity of the dosage was 96.5% (95% confidence interval, 92.5%-100%). CONCLUSIONS: Elevated D-dimer level is highly specific for VMs (pure, combined, or syndromic), and therefore this easy and inexpensive biomarker test should become part of the clinical evaluation of vascular anomalies. It can detect hidden VMs and help differentiate glomuvenous malformation (normal D-dimer levels) from other multifocal venous lesions. Elevated D-dimer level also differentiates a VM from a lymphatic malformation. Moreover, slow-flow Klippel-Trenaunay syndrome (capillaro-lymphatico-venous malformation with limb hypertrophy) can be distinguished from fast-flow Parkes Weber syndrome (capillary malformation with underlying multiple microfistulas and limb hypertrophy). For these reasons, D-dimer level measurement is a useful complementary tool for diagnosing vascular anomalies in everyday practice.

Low-molecular-weight heparin prophylaxis of deep vein thrombosis for older patients with restricted mobility: propensity analyses of data from two multicentre, cross-sectional studies.

BACKGROUND: Although older patients with restricted mobility are at increased risk for venous thromboembolism, they are under-represented in clinical trials evaluating prophylactic treatments against deep vein thrombosis (DVT). OBJECTIVE: To determine whether prolonged prophylaxis with low-molecular-weight heparin (LMWH) is associated with a lower rate of DVT in older patients with restricted mobility. METHODS: Two cross-sectional studies were conducted in 50 hospital-based, post-acute care facilities in France in 2001 and 2003. The studies included 1603 evaluable patients aged >or=65 years, including 866 LMWH users (median treatment duration 23 days; interquartile range 13-42) and 737 LMWH non-users. All patients underwent complete compression ultrasonography performed by board-certified vascular medicine physicians. The primary study outcome was proximal DVT. Propensity analyses were used to control for bias in LMWH treatment assignment. RESULTS: The rate of proximal DVT was 4% (35/866) and 5.7% (42/737) for LMWH users and non-users, respectively (p = 0.16). Prophylaxis with LMWH was associated with decreased odds of proximal DVT after adjusting for baseline characteristics (odds ratio [OR] 0.56; 95% CI 0.33, 0.95; p = 0.03) or quintile of propensity score (OR 0.58; 95% CI 0.35, 0.99; p = 0.04). In propensity matched analysis, 342 LMWH users were at decreased odds of proximal DVT compared with 342 non-users (OR 0.50; 95% CI 0.24, 1.00; p = 0.04). The decrease in proximal DVT was paralleled by a similar decrease in distal DVT. Compared with non-users, only high-risk dose users had decreased odds of DVT. CONCLUSIONS: In this observational study, prophylaxis with a high-risk dose of LMWH was associated with decreased odds of proximal DVT in older patients with restricted mobility. Further study is needed before recommending routine prophylaxis with LMWH in these patients.

Association of localized intravascular coagulopathy with venous malformations.

OBJECTIVE: To determine which venous malformations (VMs) are at risk for coagulopathy. Venous malformations are slow-flow vascular malformations present at birth, and localized intravascular coagulopathy (LIC) causes pain and thrombosis within a lesion and severe bleeding during surgical procedures. DESIGN: Prospective convenience sample accrued from 2 multidisciplinary sites in Brussels, Belgium, and Caen, France. PARTICIPANTS: The study population comprised 140 patients with clinical data and coagulation parameters. Magnetic resonance imaging was performed for 110 patients. MAIN OUTCOME MEASURE: Measurement of D-dimer levels. RESULTS: Of the 140 participants, 59 (42%) showed high D-dimer levels, 36 (61%) of whom had levels higher than 1.0 microg/mL. Six of the participants had low fibrinogen levels. In univariate analysis, large surface, presence of palpable phleboliths, and truncal localization were associated with high D-dimer levels. In the multivariate analysis, only large surface area and presence of phleboliths remained independently associated with high D-dimer levels. Severe LIC, characterized by concomitant low fibrinogen level, was associated with extensive venous malformations of the extremities. CONCLUSIONS: Localized intravascular coagulopathy is statistically significantly associated with large and/or deep venous malformations that affect any location, which can have a palpable phlebolith. These patients are at risk of local pain due to thrombosis. Lesions with elevated D-dimer levels associated with low fibrinogen levels (severe LIC) commonly affect an extremity and have a high risk of hemorrhage. Low-molecular-weight heparin can be used both to treat the pain caused by LIC and to prevent decompensation of severe LIC to disseminated intravascular coagulopathy.

Hormone therapy and venous thromboembolism among postmenopausal women: impact of the route of estrogen administration and progestogens: the ESTHER study.

BACKGROUND: Oral estrogen therapy increases the risk of venous thromboembolism (VTE) in postmenopausal women. Transdermal estrogen may be safer. However, currently available data have limited the ability to investigate the wide variety of types of progestogen. METHODS AND RESULTS: We performed a multicenter case-control study of VTE among postmenopausal women 45 to 70 years of age between 1999 and 2005 in France. We recruited 271 consecutive cases with a first documented episode of idiopathic VTE (208 hospital cases, 63 outpatient cases) and 610 controls (426 hospital controls, 184 community controls) matched for center, age, and admission date. After adjustment for potential confounding factors, odds ratios (ORs) for VTE in current users of oral and transdermal estrogen compared with nonusers were 4.2 (95% CI, 1.5 to 11.6) and 0.9 (95% CI, 0.4 to 2.1), respectively. There was no significant association of VTE with micronized progesterone and pregnane derivatives (OR, 0.7; 95% CI, 0.3 to 1.9 and OR, 0.9; 95% CI, 0.4 to 2.3, respectively). In contrast, norpregnane derivatives were associated with a 4-fold-increased VTE risk (OR, 3.9; 95% CI, 1.5 to 10.0). CONCLUSIONS: Oral but not transdermal estrogen is associated with an increased VTE risk. In addition, our data suggest that norpregnane derivatives may be thrombogenic, whereas micronized progesterone and pregnane derivatives appear safe with respect to thrombotic risk. If confirmed, these findings could benefit women in the management of their menopausal symptoms with respect to the VTE risk associated with oral estrogen and use of progestogens.

Effectiveness of a guideline for venous thromboembolism prophylaxis in elderly post-acute care patients: a multicenter study with systematic ultrasonographic examination.

BACKGROUND: Thromboprophylaxis in elderly patients, including post-acute care patients, is at variance with scientific evidence. The purpose of this study was to determine whether a multifaceted intervention was followed by a decrease in deep venous thrombosis (DVT). METHODS: A prospective preintervention-postintervention study was conducted in 1373 patients (preintervention phase, n = 709; postintervention phase, n = 664), aged 65 years or older, enrolled in 33 hospital-based post-acute care facilities in France. An evidence-based guideline addressing pharmacologic and mechanical prophylaxis was implemented through a multifaceted intervention. The main outcome measure was any DVT diagnosed at routine comprehensive ultrasonography performed by registered angiologists. RESULTS: A DVT was found in 91 patients (12.8%) in the preintervention phase and in 52 patients (7.8%) in the postintervention phase (P = .002). The decrease in DVT involved the calf (7.1% vs 3.6%; P = .005) and the proximal venous segments (5.8% vs 4.2%; P = .18) and remained significant after adjusting for risk factors (adjusted odds ratio of any DVT, 0.58; 95% confidence interval, 0.39-0.86). Pharmacologic prophylaxis with either low-molecular-weight heparin at the high-risk dose, unfractionated heparin, and vitamin K antagonist was similar in the 2 study groups, whereas patients in the postintervention group were more likely to use graduated compression stockings (27.4% vs 34.6%; P = .004) and less likely to receive low-molecular-weight heparin at the low-risk dose (24.7% vs 18.5%; P = .006), which was not recommended by our guideline. CONCLUSIONS: A multifaceted intervention addressing venous thromboembolism prophylaxis in post-acute care patients can be followed by a significant decrease in the rate of any DVT in elderly patients. More active interventions are needed to enforce compliance with evidence-based guidelines.

Prothrombotic mutations, hormone therapy, and venous thromboembolism among postmenopausal women: impact of the route of estrogen administration.

BACKGROUND: Oral estrogen increases the risk of venous thromboembolism (VTE) in postmenopausal women, particularly in those with a prothrombotic mutation. Transdermal estrogen may be safe with respect to VTE. We investigated the impact of the route of estrogen administration on the association between a prothrombotic mutation (factor V Leiden or prothrombin G20210A mutation) and VTE risk. METHODS AND RESULTS: We performed a multicenter case-control study of VTE among postmenopausal women who were enrolled in 1999 through 2004 at 7 clinical centers in France. We recruited 235 consecutive patients with a first documented episode of idiopathic VTE and 554 controls. Factor V Leiden was associated with a 3.4-fold-increased risk of VTE (95% confidence interval [CI], 2.0 to 5.8), and a prothrombin mutation was associated with a 4.8-fold-increased risk of VTE (95% CI, 2.5 to 9.4). Oral but not transdermal estrogen was associated with an increased risk of VTE (odds ratio [OR], 4.3; 95% CI, 2.6 to 7.2; and OR, 1.2; 95% CI, 0.8 to 1.7, respectively). After adjustment for potential confounding factors, the combination of either factor V Leiden or prothrombin G20210A mutation and oral estrogen gave a 25-fold-increased risk of VTE compared with nonusers without mutation (95% CI, 6.9 to 95.0). However, the risk for women with prothrombotic mutation using transdermal estrogen was similar to that of women with a mutation who were not using estrogen (OR, 4.4; 95% CI, 2.0 to 9.9; and OR, 4.1; 95% CI, 2.3 to 7.4, respectively). CONCLUSIONS: In contrast to oral estrogen, transdermal estrogen does not confer additional risk on women who carry a prothrombotic mutation. The safety of transdermal estrogen has to be confirmed in randomized trials.