The prevention of hospital-acquired venous thromboembolism in the United Kingdom

Hospital-acquired venous thromboembolism (VTE) remains the number one safety issue in hospitals and is estimated to cause more preventable deaths than the more publicized hospital-acquired infection. There has been a failure of implementation of thromboprophylaxis (TP), mainly because of lack of awareness among health professionals, despite the large number of evidence-based studies available. The situation in the UK is gradually changing because of tireless campaigning by politicians, a charity and key opinion leaders. In response, the Department of Health has issued a national risk assessment tool, and National Institute of Clinical Excellence (NICE) guidelines for the prevention of VTE in all hospitalised patients, which will be available in August 2009. Although NICE guidelines are only applicable in England, it is to be hoped Northern Ireland, Wales and Scotland will also follow. Despite this, the consensus of expert opinion is that TP needs mandating to prevent pockets of non-adherence. Low molecular weight heparins are currently the gold standard pharmacological agent for TP; but are likely to be superseded within the next 5 years by new classes of oral anticoagulants, such as dabigatran and rivaroxiban, which are already licensed for TP after orthopaedic surgery.     

Risk factors for venous thromboembolism

Venous thromboembolism is a common and potentially lethal disease. Patients who have pulmonary embolism are at especially high risk for death. Death owing to pulmonary embolism is independent of other comorbid conditions (e.g., cancer, chronic heart disease, or lung disease). Sudden death is often the first clinical manifestation. Only a reduction in the incidence of venous thromboembolism can reduce sudden death owing to pulmonary embolism and venous stasis syndrome owing to deep vein thrombosis. The incidence of venous thromboembolism has been relatively constant since about 1980. Improvement in the incidence of venous thromboembolism will require better recognition of persons at risk, improved estimates of the magnitude of risk, the avoidance of risk exposure when possible, more widespread use of safe and effective prophylaxis when risk is unavoidable, and targeting of prophylaxis to those persons who will benefit most. Recognition of venous thromboembolism as a multifactorial disease with genetic and genetic-environmental interaction has provided significant insights into its epidemiology and offers the possibility of improved identification of persons at risk for incident and recurrent venous thromboembolism.     

老年人静脉血栓栓塞症的危险因素

静脉血栓栓塞症(VTE)包括深静脉血栓形成(DVT)和肺栓塞(PE),其发生率随着年龄的增高而显著上升,老年人是VTE的高危人群。随着人口老龄化加剧,老年VTE患者势必不断增多。明确老年人VTE危险因素,及时采取有效预防措施,具有重要的现实意义。本文综述了与老年人VTE发生较为密切的一些因素,包括制动相关危险因素、癌症、老年人常见慢性病、慢性静脉功能不全、衰弱综合征等,以期发现其特点,为老年人VTE预防提供可靠的临床参考。     

Risk factors for recurrent venous thromboembolism

Recurrent venous thromboembolism (VTE) is frequent and can be fatal. Long-term antithrombotic treatment reduces the risk of recurrent VTE but increases the risk of bleeding and, therefore, cannot be proposed for all patients. Predicting the probability of recurrence in an individual patient is of utmost importance for assessing the risk-benefit ratio of long-term anticoagulation. Multiple clinical risk factors for recurrent VTE have been identified which include: unprovoked first episode, anatomical proximal location, male gender, residual venous thrombosis, cancer and antiphospholipid syndrome. d-dimer level after discontinuation of oral anticoagulation can help to predict the risk of recurrence with a good negative predictive value. Finally, genetic polymorphisms and rare inherited deficiencies of natural anticoagulant proteins do not seem to be strongly associated to recurrence. New antithrombotic drugs may, in the near future, improve the safety and of long-term anticoagulation treatment.     

Risk factors for venous thromboembolism in children.

The incidence of venous thromboembolism (VTE) is increasing in children as a result of therapeutic advances and improved clinical outcome in primary illnesses that previously caused mortality. VTE is mostly diagnosed in hospitalized children, especially sick newborns with central venous catheters and older children with a combination of risk factors. Infants older than 3 months and teenagers are the largest groups developing VTE. The most important triggering risk factors are the presence of central venous lines, cancer and chemotherapy. Pathological conditions such as severe infection, sickle cell disease, trauma and antiphospholipid syndrome are associated with the presence of a hypercoagulable state in children. The thrombotic risk in otherwise healthy children with a single identified thrombophilic defect appears to be extremely low. Venous thromboembolism in pediatric patients is mainly caused by combinations of at least 2 prothrombotic risk factors for venous thromboembolic events in children are usually associated with underlying clinical conditions and a triggering risk factor. In addition, recurrence of VTE after withdrawal of anticoagulant treatment occurs in about 20% of patients after re-exposure to a triggering risk factor. A non negligible mortality and morbidity is related to VTE in childhood. This supports the need for international multicenter randomized clinical trials to determine optimal prophylactic and therapeutic treatment for children with VTE. Risk factor assessment for VTE in children has to be improved in order to optimize the prophylactic and therapeutic strategies. The specific evolutionary characteristics of the hemostasis in children has to be taken into consideration when a prophylactic or therapeutic strategy is applied.The incidence of venous thromboembolism (VTE) is increasing in children as a result of therapeutic advances and improved clinical outcome in primary illnesses that previously caused mortality. VTE is mostly diagnosed in hospitalized children, especially sick newborns with central venous catheters and older children with a combination of risk factors. Infants older than 3 months and teenagers are the largest groups developing VTE. The most important triggering risk factors are the presence of central venous lines, cancer and chemotherapy. Pathological conditions such as severe infection, sickle cell disease, trauma and antiphospholipid syndrome are associated with the presence of a hypercoagulable state in children. The thrombotic risk in otherwise healthy children with a single identified thrombophilic defect appears to be extremely low. Venous thromboembolism in pediatric patients is mainly caused by combinations of at least 2 prothrombotic risk factors for venous thromboembolic events in children are usually associated with underlying clinical conditions and a triggering risk factor. In addition, recurrence of VTE after withdrawal of anticoagulant treatment occurs in about 20% of patients after re-exposure to a triggering risk factor. A non negligible mortality and morbidity is related to VTE in childhood. This supports the need for international multicenter randomized clinical trials to determine optimal prophylactic and therapeutic treatment for children with VTE. Risk factor assessment for VTE in children has to be improved in order to optimize the prophylactic and therapeutic strategies. The specific evolutionary characteristics of the hemostasis in children has to be taken into consideration when a prophylactic or therapeutic strategy is applied.     

Risk factors for venous thromboembolism in pregnancy.

Venous thromboembolism remains the leading cause of maternal mortality in the United Kingdom. In this review we highlight studies that have documented the incidence of objectively confirmed venous thromboembolism in pregnancy, consider the effect of pregnancy on the coagulation and fibrinolytic systems, and examine in detail current knowledge of the risk factors for the development of this condition.     

Risk factors for venous thromboembolism after lung transplantation

BACKGROUND: The risk factors for venous thromboembolism (VTE) following lung transplantation are not well established. We aimed to estimate the incidence of VTE and to identify the risk factors for VTE after lung transplantation. METHODS: We performed a nested case-control study within the cohort of 121 patients who underwent lung transplantation at our center between August 2001 and July 2005. Control subjects were matched to case patients on the number of days from the time of transplant. Cox proportional hazards models were used to identify risk factors for VTE. RESULTS: Twenty-four patients had deep vein thromboses, and 6 patients had pulmonary emboli (3 patients had both) [22% of the cohort]. In multivariate models, older age (p < 0.05), diabetes mellitus (p = 0.03), and pneumonia (p = 0.02) were associated with a higher rate of VTE. CONCLUSIONS: VTE is a frequent complication of lung transplantation. Older age, diabetes, and pneumonia increase the rate of VTE. Future studies of intensive VTE prophylaxis may be warranted.     

The impact of buprenorphine and methadone on mortality: a primary care cohort study in the United Kingdom

Aims

To estimate whether opioid substitution treatment (OST) with buprenorphine or methadone is associated with a greater reduction in the risk of all‐cause mortality (ACM) and opioid drug‐related poisoning (DRP) mortality.

Design

Cohort study with linkage between clinical records from Clinical Practice Research Datalink and mortality register.

Setting

UK primary care.

Participants

A total of 11 033 opioid‐dependent patients who received OST from 1998 to 2014, followed‐up for 30 410 person‐years.

Measurements

Exposure to methadone (17 373, 61%) OST episodes or buprenorphine (9173, 39%) OST episodes. ACM was available for all patients; information on cause of death and DRP was available for 5935 patients (54%) followed‐up for 16 363 person‐years. Poisson regression modelled mortality by treatment period with an interaction between OST type and treatment period (first 4 weeks on OST, rest of time off OST, first 4 weeks off OST, rest of time out of OST censored at 12 months) to test whether ACM or DRP differed between methadone and buprenorphine. Inverse probability weights were included to adjust for confounding and balance characteristics of patients prescribed methadone or buprenorphine.

Findings

ACM and DRP rates were 1.93 and 0.53 per 100 person‐years, respectively. DRP was elevated during the first 4 weeks of OST [incidence rate ratio (IRR) = 1.93 95% confidence interval (CI) = 0.97–3.82], the first 4 weeks off OST (IRR = 8.15, 95% CI = 5.45–12.19) and the rest of time out of OST (IRR = 2.13, 95% CI = 1.47–3.09) compared with mortality risk from 4 weeks to end of treatment. Patients on buprenorphine compared with methadone had lower ACM rates in each treatment period. After adjustment, there was evidence of a lower DRP risk for patients on buprenorphine compared with methadone at treatment initiation (IRR = 0.08, 95% CI = 0.01–0.48) and rest of time on treatment (IRR = 0.37, 95% CI = 0.17–0.79). Treatment duration (mean and median) was shorter on buprenorphine than methadone (173 and 40 versus 363 and 111, respectively). Model estimates suggest that there was a low probability that methadone or buprenorphine reduced the number of DRP in the population: 28 and 21%, respectively.

Conclusions

In UK general medical practice, opioid substitution treatment with buprenorphine is associated with a lower risk of all‐cause and drug‐related poisoning mortality than methadone. In the population, buprenorphine is unlikely to give greater overall protection because of the relatively shorter duration of treatment.     

Risk factors for venous thromboembolism in immunoglobulin light chain amyloidosis

Patients with immunoglobulin light chain amyloidosis are at risk for both thrombotic and bleeding complications. While the hemostatic defects have been extensively studied, less is known about thrombotic complications in this disease. This retrospective study examined the frequency of venous thromboembolism in 929 patients with immunoglobulin light chain amyloidosis presenting to a single referral center, correlated risk of venous thromboembolism with clinical and laboratory factors, and examined complications of anticoagulation in this population. Sixty-five patients (7%) were documented as having at least one venous thromboembolic event. Eighty percent of these patients had events within one year prior to or following diagnosis. Lower serum albumin was associated with increased risk of VTE, with a hazard ratio of 4.30 (CI 1.60–11.55; P=0.0038) for serum albumin less than 3 g/dL compared to serum albumin greater than 4 g/dL. Severe bleeding complications were observed in 5 out of 57 patients with venous thromboembolism undergoing treatment with anticoagulation. Prospective investigation should be undertaken to better risk stratify these patients and to determine the optimal strategies for prophylaxis against and management of venous thromboembolism.     

非小细胞肺癌合并静脉血栓栓塞症危险因素研究

目的 探讨非小细胞肺癌(NSCLC)患者发生静脉血栓栓塞症(VTE)的危险因素.方法 回顾性分析2005年1月至2016年1月新疆医科大学第一附属医院收治的57例NSCLC合并VTE患者的资料,选取同期在我院确诊为NSCLC的患者105例,用二元logistic回归分析NSCLC患者并发VTE的可能危险因素.结果 二元logistic回归多因素分析显示,化疗(OR =5.91,95％CI:1.47～10.76)、白细胞＞11×109/L(OR=7.54,95％ CI:1.69～13.25)、白蛋白＜35 g/L(OR =5.25,95％ CI:1.89～12.42)、D-二聚体＞500 μg/L(OR=25.16,95％ CI:7.87～80.41)与NSCLC患者发生VTE存在显著的相关关系.结论 化疗、白细胞＞1i×109/L、白蛋白＜35 g/L、D-二聚体＞500 μg/L是NSCLC患者并发VTE的独立危险因素.     

Risk factors for venous thromboembolism in the elderly: results of the master registry

Approximately 50-75% of patients with venous thromboembolism have a readily identifiable risk factor, either transient or permanent, whereas the remaining episodes are classified as unprovoked. The incidence of first-time venous thromboembolism rises exponentially with age. Whether the prevalence and the relative weight of major risk factors differ between elderly and younger patients is unclear. We performed a multicenter, prospective, observational study on consecutive patients with objectively confirmed acute venous thromboembolism admitted to 25 Italian hospitals. Baseline characteristics and information on temporary and permanent risk factors at the time of the index event were secured by an electronic data network. We enrolled 2119 patients (49.8% men), of whom 440 (20%) were more than 75 years of age and 1679 (79.2%) 75 years of age or less. Elderly patients were more likely to have pulmonary embolism at presentation (33.6 and 25.6%, respectively, P < 0.001). After binary logistic regression analysis, we found that the risk of venous thromboembolism in the elderly, compared with the younger age group, was significantly associated with immobilization (odds ratio: 2.46, 95% confidence interval: 1.85-3.27) and with severe medical disorders (odds ratio: 1.99, 95% confidence interval: 1.41-2.80), whereas male sex (odds ratio: 0.53, 95% confidence interval: 0.42-0.66), surgery (odds ratio: 0.61, 95% confidence interval: 0.43-0.85), and trauma (odds ratio: 0.49, 95% confidence interval: 0.31-0.77) were less common risk factors in the elderly than in younger patients. Use of thromboprophylaxis prior to the index event was not different between the two age groups. Severe medical disorders and immobilization are strongly associated with the occurrence of venous thromboembolism in the elderly. Our findings stress the need for adequate thromboprophylaxis in this setting.     

重症监护病房住院患者发生静脉血栓的风险和预防措施

目的:观察ICU患者静脉血栓形成(VTE)的风险,评估间歇充气加压治疗(IPC)对VTE的临床预防作用。方法:选择ICU住院患者326例,随机分为对照组和IPC观察组,每组163例,采用Caprini量表进行VTE风险评估。结果:326例ICU患者Caprini评分为(9.3±2.3)分,其中无风险占2.15%,低风险占5.52%,中风险占10.12%,高风险占15.95%,极高风险占66.26%。相关性分析显示Caprini评分与患者的性别和年龄之间无显著的相关性(P0.05),但与患者的APACHEⅡ评分呈显著的正相关(r=0.416,P0.05)。对照组ICU住院时间显著长于观察组(P0.05)。VTE发生率观察组显著低于对照组(4.91%vs16.56%,P0.05)。结论:ICU病房患者存在VTE高风险,IPC可以显著减低VTE发生率。