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.

Brief report: graduated compression stocking thromboprophylaxis for elderly inpatients: a propensity analysis.

BACKGROUND: Graduated compression stockings (GCS) are often used for deep vein thrombosis prophylaxis in nonsurgical patients, although evidence on their effectiveness is lacking in this setting. OBJECTIVE: To determine whether prophylaxis with GCS is associated with a decrease in the rate of deep vein thrombosis in nonsurgical elderly patients. METHODS: Using original data from 2 multicenter nonrandomized studies, we performed multivariable and propensity score analyses to determine whether prophylaxis with GCS reduced the rate of deep vein thrombosis among 1,310 postacute care patients 65 years or older. The primary outcome was proximal deep vein thrombosis detected by routine compression ultrasonography performed by registered vascular physicians. RESULTS: Proximal deep vein thrombosis was found in 5.7% (21/371) of the GCS users and in 5.2% (49/939) of the GCS nonusers (odds ratio [OR], 1.09; 95% confidence interval [CI], 0.64-1.84). Although adjusting for propensity score eliminated all differences in baseline characteristics between users and nonusers, the OR for proximal deep vein thrombosis associated with GCS remained nonsignificant in propensity-stratified (adjusted OR, 1.11; 95% CI, 0.59-2.10) and propensity-matched (conditional OR, 0.92; 95% CI, 0.42-2.02) analysis. Similar figures were observed for distal and any deep vein thrombosis. The rates of deep vein thrombosis did not differ according to the length of stockings. CONCLUSIONS: Prophylaxis with GCS is not associated with a lower rate of deep vein thrombosis in nonsurgical elderly patients in routine practice. Randomized studies are needed to assess the efficacy of GCS when properly used in this setting.

Intervention targeted at nurses to improve venous thromboprophylaxis.

OBJECTIVE: To assess the effectiveness of an intervention targeting both physicians and nurses vs. physicians only in improving venous thromboprophylaxis for older patients. DESIGN: Cluster randomized trial. SETTING: Fifty hospital-based post-acute care departments in France. PARTICIPANTS: Patients aged 65 years or older. INTERVENTION: A multifaceted intervention to implement a clinical practice guideline addressing venous thromboprophylaxis. MAIN OUTCOME MEASURES: The effectiveness outcomes were elastic stocking use, ambulation or mobilization under the supervision of a physical therapist and anticoagulant-based prophylaxis. Patient outcomes included deep vein thrombosis and anticoagulant-related adverse events. RESULTS: One department allocated to the intervention targeted at physicians only and seven departments allocated to the intervention targeted at both physicians and nurses dropped out of the study. Compared with the intervention targeted at physicians only (n = 497 patients), the intervention targeted at both physicians and nurses (n = 315 patients) was associated with a higher rate of mobilization (62 vs. 37%, P < 0.001) and comparable levels of elastic stocking (32 vs. 39%, P = 0.74) and anticoagulant (55 vs. 48%, P = 0.36) use. The rates of deep vein thrombosis (15 vs. 13%, P = 0.50), bleeding (1 vs. 1%, P = 0.99) and thrombocytopaenia (0 vs. 0.2%, P = 0.99) did not differ between the two groups. CONCLUSIONS: A multifaceted intervention targeting nurses in addition to physicians can increase the frequency of mobilization of older patients to prevent venous thromboembolism but does not alter the use of elastic stockings and anticoagulant. A differential drop-out of departments might have contributed to creating imbalances in baseline characteristics and outcomes in this study.