Relationship between neighborhood socioeconomic status and venous thromboembolism: results from a population-based study.

Essentials Literature on socioeconomic status (SES) and incidence of venous thromboembolism (VTE) is scarce. We assessed neighborhood SES with VTE risk in a population of over 1.4 million inhabitants. Higher neighborhood SES was associated with lower incidence of VTE. These findings are helpful to inform policy and resource allocation in health systems. SUMMARY: Background The association between socioeconomic status and arterial cardiovascular disease is well established. However, despite its high burden of disability-adjusted life years, little research has been carried out to determine whether socioeconomic status is associated with venous thromboembolism. Objective To determine if neighborhood socioeconomic status is associated with venous thromboembolism in a population-based study from the Netherlands. Methods We identified all patients aged 15 years and older with a first event of venous thromboembolism from inhabitants who lived in the urban districts of The Hague, Leiden and Utrecht in the Netherlands in 2008-2012. Neighborhood socioeconomic status was based on the status score, which combines educational level, income and unemployment on a four-digit postal code level. Incidence rate ratios of venous thromboembolism were calculated for different levels of neighborhood socioeconomic status, with adjustments for age and sex. Results A total of 7373 patients with a first venous thromboembolism (median age 61 years; 50% deep vein thrombosis) were identified among more than 1.4 million inhabitants. Higher neighborhood SES was associated with lower incidence of VTE. In the two highest status score groups (i.e. the 95-99th and > 99th percentile), the adjusted incidence rate ratios were 0.91 (95% confidence interval [CI], 0.84-1.00) and 0.80 (95% CI, 0.69-0.93), respectively, compared with the reference status score group (i.e. 30-70th percentile). Conclusions High neighborhood socioeconomic status is associated with a lower risk of first venous thromboembolism.

Major bleeding risks of different low-molecular-weight heparin agents: a cohort study in 12 934 patients treated for acute venous thrombosis.

Essentials Low-molecular-weight-heparins (LMWH) kinetics differ which may result in different bleeding risks. A cohort of 12 934 venous thrombosis patients on LMWH was followed until major bleeding. The absolute major bleeding risk was low among patients registered at the anticoagulation clinic. Once-daily dosing was associated with a lower bleeding risk as compared with twice-daily. SUMMARY: Background Low-molecular-weight heparins (LMWHs) are considered members of a class of drugs with similar anticoagulant properties. However, pharmacodynamics and pharmacokinetics between LMWHs differ, which may result in different bleeding risks. As these agents are used by many patients, small differences may lead to a large effect on numbers of major bleeding events. Objectives To determine major bleeding risks for different LMWH agents and dosing schedules. Methods A cohort of acute venous thrombosis patients from four anticoagulation clinics who used an LMWH and a vitamin K antagonist were followed until they ceased LMWH treatment or until major bleeding. Exposures were classified according to different types of LMWHs and for b.i.d. and o.d. use. Cumulative incidences for major bleeding per 1000 patients and risk ratios were calculated and adjusted for study center. Results The study comprised 12 934 patients with a mean age of 59 years; 6218 (48%) were men. The cumulative incidence of major bleeding was 2.5 per 1000 patients (95% confidence interval [CI], 1.7-3.5). Enoxaparin b.i.d. or o.d. was associated with a relative bleeding risk of 1.7 (95% CI, 0.2-17.5) compared with nadroparin o.d. In addition, a nadroparin b.i.d. dosing schedule was associated with a 2.0-fold increased major bleeding risk (95% CI, 0.8-5.1) as compared with a nadroparin o.d. dosing schedule. Conclusions Absolute major bleeding rates were low for all LMWH agents and dosing schedules in a large unselected cohort. Nevertheless, twice-daily dosing with nadroparin appeared to be associated with an increased major bleeding risk as compared with once-daily dosing, as also suggested in a meta-analysis of controlled clinical trials.

Anticoagulant bridging in left-sided mechanical heart valve patients.

BACKGROUND: In preparation for an invasive procedure with a high bleeding risk, patients with a mechanical heart valve temporarily have to discontinue their anticoagulant therapy and are usually bridged with either intravenous unfractionated heparin (UFH) or subcutaneous low-molecular-weight heparin (LMWH). In this study we retrospectively analyzed the safety of UFH versus LMWH as bridging strategy in left-sided mechanical heart valve patients. METHODS: We performed a retrospective multicenter study in four surgical centers in The Netherlands. Patients with a mechanical heart valve implantation bridged from January 2010 until January 2015 were included. The cumulative incidence of adverse events in the 30days following the procedure was recorded. Main outcomes were major bleeding according to International Society on Thrombosis and Haemostasis (ISTH) criteria, symptomatic thromboembolism, and mortality. RESULTS: In total, 238 (174 aortic, 42 mitral, 22 aortic+mitral) bridging episodes were included. The incidence of major bleeding was 16 (19%) events in the UFH group versus 29 (19%) events in the LMWH group (p=0.97). Incidences of thromboembolism were 2 (2.4%) versus 1 (0.6%). The incidence of death was 1 (1.2%) patient in the UFH group versus 3 (1.9%) patients in the LMWH group. More than 50% of all bleeding complications were categorized as a major bleeding. CONCLUSIONS: Bridging anticoagulation in patients with aortic and mitral mechanical valves is associated with considerable risk, but no difference was apparent between UFH and LMWH strategy. The rate of thromboembolism and death was low with either strategy and the vast majority of adverse events were bleedings.