Antonella Tufano

The first ambulatory screening on thromboembolism: a multicentre, cross‐sectional, observational study on risk factors for venous thromboembolism

Summary.  Objectives: To assess the prevalence of risk factors for venous thromboembolism (VTE) and the prevalence of recent (<1 year) VTE [including superficial vein thrombosis (SVT), deep vein thrombosis (DVT) and pulmonary embolism (PE)] amongst patients attending general practitioner (GP) surgeries. Design: Multicentre, cross‐sectional, observational study. Setting: A total of 1536 GP surgeries. Participants: A total of 15 180 adult, co‐operative subjects, who had consulted their GP for a health disorder and signed the informed consent form. Interventions: None. Main outcome measures: Prevalence of known VTE risk factors graded according to importance and prevalence of recent (<1 year) VTE events (including SVT), based on interviews. Results: About 1:5 patients had at least one strong risk factor and about 1:20 had at least two risk factors, with no difference between sexes. The prevalence of strong risk factors increased with age. Most were related to medical conditions: history of SVT and/or DVT/PE, heart failure and malignancy. About 3:4 women and 2:3 men had at least one moderate to weak risk factor; nearly 1:2 women and 1:3 men had at least two moderate to weak risk factors. The most common were: history of VTE, smoking, history of miscarriage, estrogen therapy, obesity, and varicose veins. Overall, 80% women and 67% men had at least one risk factor, and 50% women and 35% men had at least two risk factors. The prevalence of recent (<1 year) VTE was 3.4% in women and 2.4% in men, and increased with age. The majority of cases were SVT in both sexes (2.5% in women and 1.5% in men). Conclusions: The prevalence of risk factors for VTE amongst patients attending GP surgeries is high. GPs should bear this in mind during their daily practice.

Inherited Thrombophilia: Implications for Prevention and Treatment of Venous Thromboembolism

Inherited thrombophilia, defined as a genetically determined tendency to develop venous thromboembolism (VTE), contributes to the pathogenesis of approximately 40% of VTE episodes. About 50% of carriers of inherited thrombophilic traits develop VTE, but the impact of the different abnormalities is variable in terms of clinical penetrance. Some rare abnormalities (natural anticoagulant deficiencies, homozygous factor V Leiden, and combined defects) result in more severe thrombophilic phenotypes, characterized by early-onset events, more frequent recurrence, and positive family history, whereas the common polymorphisms (heterozygous factor V Leiden and prothrombin G20210A) are associated with lower VTE risk, often in association with triggering risk factors. Therefore, clinical implications of inherited thrombophilia should be assessed in the framework of coexisting and/or circumstantial risk factors involved in the multifactorial pathogenesis of VTE. These considerations should be taken into account when assessing the need and modalities of primary and secondary thromboprophylaxis in patients carrying inherited thrombophilic traits.

Treatment of hemophilia: a review of current advances and ongoing issues.

Replacement of the congenitally deficient factor VIII or IX through plasma-derived or recombinant concentrates is the mainstay of treatment for hemophilia. Concentrate infusions when hemorrhages occur typically in joint and muscles (on-demand treatment) is able to resolve bleeding, but does not prevent the progressive joint deterioration leading to crippling hemophilic arthropathy. Therefore, primary prophylaxis, ie, regular infusion of concentrates started after the first joint bleed and/or before the age of two years, is now recognized as first-line treatment in children with severe hemophilia. Secondary prophylaxis, whenever started, aims to avoid (or delay) the progression of arthropathy and improve patient quality of life. Interestingly, recent data suggest a role for early prophylaxis also in preventing development of inhibitors, the most serious complication of treatment in hemophilia, in which multiple genetic and environmental factors may be involved. Treatment of bleeds in patients with inhibitors requires bypassing agents (activated prothrombin complex concentrates, recombinant factor VIIa). However, eradication of inhibitors by induction of immune tolerance should be the first choice for patients with recent onset inhibitors. The wide availability of safe factor concentrates and programs for comprehensive care has now resulted in highly satisfactory treatment of hemophilia patients in developed countries. Unfortunately, this is not true for more than two-thirds of persons with hemophilia, who live in developing countries.

Acquired inhibitors of coagulation factors: part I-acquired hemophilia A.

Acquired hemophilia A (AHA) is a rare, but often severe, bleeding disorder caused by autoantibodies against clotting factor VIII (FVIII). AHA occurs more frequently in the elderly and in association with several conditions, such as malignancies, autoimmune diseases, postpartum, or drug exposure; however, about half of the cases remain idiopathic. At variance with congenital hemophilia, where hemarthroses are the most common bleeding symptoms, hemorrhages in AHA involving soft tissues (muscle, skin) are more frequently reported. AHA is diagnosed in patients: with negative personal or family bleeding history; in which prolonged activated partial thromboplastin time is not corrected after mixing and incubating equal volumes of patient and normal plasma for ~2 hours at 37°C; FVIII levels are reduced; and a specific FVIII-inhibiting activity is detected. Prompt recognition and treatment of AHA are mandatory, as inadequate management and complications of the disease are associated with high mortality rates. Therapeutic approaches should aim to control acute bleeds, eradicate FVIII-autoantibody production, treat associated diseases, and when possible, eliminate them. Present knowledge about this often overlooked and challenging condition has significantly increased following establishment of recent national and international studies, as will also be reviewed in this article.

Challenges in the prevention of venous thromboembolism in the elderly

Summary.  Aging itself is a risk factor for venous thromboembolism, and the prevalence in the elderly of additional risk factors (e.g. cancer, orthopedic surgery, immobility) increase its intrinsic risk. Many in the medical community are reluctant to prescribe anticoagulation (for primary and secondary prevention of venous thromboembolism) to their geriatric patients for the fear that bleeding complications may outweigh the benefits. A thorough analysis of the data support the concept that the under‐use of heparin in primary prevention in the elderly is more related to medical beliefs than to facts. The risk of bleeding due to oral anticoagulants (secondary prevention) is greatly reduced by keeping the International Normalized Ratio (INR) values within therapeutic ranges and carefully avoiding conditions/drugs that may interfere with such treatment. The oral direct thrombin inhibitor ximelagatran has been studied for primary (hip and knee replacement surgery) and for secondary prophylaxis of venous thromboembolism, and for acute venous thromboembolism treatment. The selective factor Xa inhibitor fondaparinux has been approved for primary prophylaxis of venous thromboembolism in hip and knee replacement surgery and in hip fracture surgery. Studies on the latter drugs, where most of the patients were > 65 years of age, further show that the fear of bleeding complications due to anticoagulation in the elderly is largely unjustified.

Abnormally high prevalence of major components of the metabolic syndrome in subjects with early-onset idiopathic venous thromboembolism

BACKGROUND Although patients with idiopathic VTE are at higher than normal risk of asymptomatic atherosclerosis and of cardiovascular events, the impact of cardiovascular risk factors on VTE is poorly understood. OBJECTIVE To assess the prevalence of the metabolic syndrome and of its components in patients with early-onset idiopathic VTE. METHODS As many as 323 patients referred to our Thrombosis Ward for a recent (<6-months) early-onset idiopathic venous thromboembolism (VTE), were compared with 868 gender- and age-matched subjects, in whom a history of venous thrombosis had been excluded, referred during the same period time to our Ward. All had undergone a clinical assessment for smoking habits and for the presence of the components of the metabolic syndrome. RESULTS The metabolic syndrome was detected in 76/323 cases (23.5%) and in 81/868 controls (9.3%) (p<0.001; OR:2.990; 95%C.I.:2.119-4.217). Smoking was more common in patients with idiopathic VTE than in controls. In addition to the metabolic syndrome as a whole, its major individual determinants (arterial hypertension, impaired fasting glucose plasma levels, abdominal obesity, hypertriglyceridemia, low HDL-cholesterol) significantly correlated with idiopathic VTE (p always <0.05). The prevalence of thrombotic events was lower in females than in males (p=0.000; OR:2.217), the latter being most often hypertensives, smokers, hypertriglyceridemics, carriers of a metabolic syndrome and of impaired fasting glucose than females. In a multivariate analysis, arterial hypertension, impaired fasting glucose, abdominal obesity, and hypercholesterolemia independently predicted idiopathic venous events. CONCLUSIONS Both metabolic syndrome as a whole and its major components individually considered, independently predict early-onset idiopathic VTE.

Ensuring medication adherence with direct oral anticoagulant drugs Lessons from adherence with vitamin K antagonists (VKAs)

Medication adherence (taking drugs properly) is uncommon among patients on warfarin. Poor adherence to warfarin leads to an increase in adverse medical events, including stroke in atrial fibrillation (AF). Factors related to patients, physicians and the health system account for poor adherence. Direct oral anticoagulants (DOACs) are easier to use than warfarin, with fewer drug and food interactions and no need for routine blood monitoring. A proper use of DOACs may reduce the risk of stroke in AF. However, in clinical settings where no laboratory monitoring is needed, a poor medication adherence is common and may impact clinical outcomes. In the management of chronic disorders, careful knowledge of the individual patients attitudes and behaviors is a pre-requisite for a successful doctor-patient communication. To increase patients awareness of the risks and benefits of DOACs and, in turn, increase medication adherence, at each follow-up visit physicians should screen for priorities and motivational problems; check for the lack of understanding and/or knowledge; assess any health system or personal barriers to medication adherence; identify appropriate interventions and provide tailored support to patient needs. Dissemination of guidelines to the health care chain (prescribing physician, general practitioners, caregivers, nurses, pharmacists) further encourages medication adherence. However, the long-term effect of some of these strategies is unknown; one tool may not fit all patients, and the prescribing physician should consider individualization of these aids to ensure medication adherence and persistence (continuing to take drugs properly in long-term treatments) for DOACs in every day practice.

Identifying high-risk individuals for cardiovascular disease: similarities between venous and arterial thrombosis in perspective. A 2011 update.

The aim of this narrative review is to assess the potential association between arterial and venous thrombotic events. Several studies have suggested that the major cardiovascular risk factors, alone or in combination (e.g. in the metabolic syndrome), are significantly associated with venous thromboembolism (VTE). Recent evidence also suggests that microalbuminuria and non-alcoholic liver steatosis, both markers of arterial disease, may independently predict the risk for VTE. An association between a history of VTE and the risk of future arterial events is also well documented, inflammation and endothelial dysfunction being thought as the common soil on which further investigation in the area should be pursued. The existence of a common pathophysiologic background is also suggested by the evidence that aspirin, low-molecular weight heparin (LMWH) and warfarin are recommended for the prevention and treatment of both venous and arterial thrombosis. In addition, rosuvastatin recently has been shown to prevent venous thromboembolism (VTE) in a time-dependent fashion. Together, these data argue for patients with a history of VTE as being at intermediate/high cardiovascular risk, a concept that implies that VTE patients should undergo a careful assessment for the presence of cardiovascular risk factors and adequate lifestyle changes. The value of routine screening for asymptomatic atherosclerosis (e.g. 2D echocardiography, microalbuminuria, arterial vessel ultrasonography) in these patients should be confirmed in future studies.

Bleeding and thrombosis in multiple myeloma and related plasma cell disorders.

A variety of disease- and treatment-related factors affect the coagulation system and the risk of bleeding and thrombotic complications in patients with multiple myeloma (MM) and related plasma cell disorders (PCD). As commonly observed in other cancer settings, the malignant clone induces a cytokine environment responsible for a hypercoagulable state. The increase of blood viscosity and impairment of platelet and coagulation function due to circulating monoclonal proteins are considered key mechanisms in the hemostatic abnormalities frequently detected in patients with PCD. However, clinically significant bleeding is relatively rare and poorly correlated with these abnormalities. Management is often challenging because of the multifactorial pathogenesis and underestimation or misdiagnosis of acquired bleeding disorders, particularly acquired von Willebrand syndrome. In recent years, growing interest in thromboembolic risk has emerged after the introduction of novel and more effective antimyeloma agents (thalidomide and lenalidomide), which was associated with increased risk of venous thromboembolism, particularly when associated with dexamethasone and multiagent chemotherapy in newly diagnosed patients. The clinical impact of bleeding and thrombotic complications in patients with PCD, with emphasis on MM, will be discussed in this review, reporting the current knowledge about pathophysiologic mechanisms and implications for management.

Air pollution, vascular disease and thrombosis: linking clinical data and pathogenic mechanisms

Summary.  The public health burden of air pollution has been increasingly recognized over the last decades. Following the first assessed adverse effects on respiratory diseases and lung cancer, a large body of epidemiologic and clinical studies definitely documented an even stronger association of air pollution exposure with cardiovascular mortality and morbidity, particularly related to atherothrombotic (coronary and cerebrovascular) disease. Particulate matter (PM), mainly that with lower aerodynamic diameter (fine and ultrafine PM), is responsible for the most severe effects, due to its capacity to transport toxic substances deep into the lower airways. These effects have been shown to occur not only after short‐term exposure to elevated concentrations of pollutants, but even after long‐term relatively low levels of exposure. Vulnerable subjects (elderly persons and those with preexisting cardiopulmonary diseases) show the highest impact. Fewer and conflicting data also suggest an association with venous thromboembolism. Although not completely elucidated, a series of mechanisms have been hypothesized and tested in experimental settings. These phenomena, including vasomotor and cardiac autonomic dysfunction, hemostatic unbalance, oxidative stress and inflammatory response, have been shown to change over time and differently contribute to the short‐term and long‐term adverse effects of pollution exposure. Beyond environmental health policies, crucial for improving air quality and reducing the impact of such an elusive threat to public health, the recognition and assessment of the individual risk, together with specific advice, should be routinely implemented in the strategies of primary and secondary cardiovascular prevention.