Venous thromboembolism and anticoagulant therapy in pregnancy

Background:Venous thromboembolism (VTE) is a leading cause of maternal mortality in western countries. Many of these deaths could be prevented by optimal prophylaxis and management.Objective:The aim of this study was to examine the current literature to assess the risk of VTE in pregnant women and to identify the most effective and safe anticoagulant therapy.Methods:A search was conducted using the major electronic databases of PubMed and MEDLINE 1996–October 2005 using the following key words: Pregnancy, venous thrombosis, thrombophilia, prosthetic heart valves, anticoagulants, heparin, low-molecular-weight heparin, coumarin, and warfarin.Results:The common risk factors for VTE during pregnancy are age >35 years, obesity, operative delivery, thrombophilia, and a family or personal history of VTE. Coumarins are unsuitable for use during pregnancy because of embryopathy and risk of fetal bleeding. Low-molecular-weight heparins (LMWHs), such as enoxaparin and dalteparin, are safer and more convenient than unfractionated heparin (UFH). LMWH is now the agent of choice for pharmacologic thromboprophylaxis and treatment of VTE during pregnancy. Women with a suspected VTE should receive anticoagulant therapy until an objective diagnostic test is performed, unless there is a clear contraindication to anticoagulation. If a VTE is confirmed, anticoagulant treatment should be continued throughout pregnancy. These patients usually, require at least 6 months of anticoagulation, and treatment should be continued until at least 6 weeks postpartum. Management of women with prosthetic heart valves in pregnancy is controversial; while coumarin treatment is more effective than UFH for thromboprophylaxis in the mother, UFH is associated with a better outcome for the fetus. Coumarin embryopathy can be avoided if heparin is substituted by 6 weeks' gestation. The limited data on LMWH in women with prosthetic heart valves suggest that it compares favorably with UFH.Conclusions:LMWH is now the anticoagulant of choice for the treatment and prevention of VTE in pregnancy. However, the management of women with prosthetic heart valves requiring anticoagulation in pregnancy remains controversial as coumarins appear safer for the mother, but heparin is associated with less fetal morbidity and data on LMWH are limited.     

Venous thromboembolism and AB0 blood groups in a Brazilian population

Summary The AB0 blood groups were determined in 125 patients suffering from venous thrombosis in a Brazilian population. There is a clear effect of the sex on the disease incidence, women being more frequently affected, but the mean age was not different regarding the sex. No differences were found in the disease incidence when Caucasians and Negroids were compared. An excess of blood group A and a decrease of blood group 0 was observed among the patients. The analysis of the combined data from ten different published series shows a A/0 relative incidence significantly higher than unity, but the heterogeneity was also significant in the series.     

Hormone replacement therapy and risk of venous thromboembolism in postmenopausal women: systematic review and meta-analysis

Objective To assess the risk of venous thromboembolism in women using hormone replacement therapy by study design, characteristics of the therapy and venous thromboembolism, and clinical background.Design Systematic review and meta-analysis.Data sources Medline.Studies reviewed Eight observational studies and nine randomised controlled trials.Inclusion criteria Studies on hormone replacement therapy that reported venous thromboembolism.Review measures Homogeneity between studies was analysed using χ² and I² statistics. Overall risk of venous thromboembolism was assessed from a fixed effects or random effects model.Results Meta-analysis of observational studies showed that oral oestrogen but not transdermal oestrogen increased the risk of venous thromboembolism. Compared with non-users of oestrogen, the odds ratio of first time venous thromboembolism in current users of oral oestrogen was 2.5 (95% confidence interval 1.9 to 3.4) and in current users of transdermal oestrogen was 1.2 (0.9 to 1.7). Past users of oral oestrogen had a similar risk of venous thromboembolism to never users. The risk of venous thromboembolism in women using oral oestrogen was higher in the first year of treatment (4.0, 2.9 to 5.7) compared with treatment for more than one year (2.1, 1.3 to 3.8; P<0.05). No noticeable difference in the risk of venous thromboembolism was observed between unopposed oral oestrogen (2.2, 1.6 to 3.0) and opposed oral oestrogen (2.6, 2.0 to 3.2). Results from nine randomised controlled trials confirmed the increased risk of venous thromboembolism among women using oral oestrogen (2.1, 1.4 to 3.1). The combination of oral oestrogen and thrombogenic mutations or obesity further enhanced the risk of venous thromboembolism, whereas transdermal oestrogen did not seem to confer additional risk in women at high risk of venous thromboembolism.Conclusion Oral oestrogen increases the risk of venous thromboembolism, especially during the first year of treatment. Transdermal oestrogen may be safer with respect to thrombotic risk. More data are required to investigate differences in risk across the wide variety of hormone regimens, especially the different types of progestogens.     

Primary antiphospholipid antibody syndrome—one further aspect of thrombophilia in overweight and obese patients with venous thromboembolism

Objective: Overweight and obesity are established risk factors for venous thromboembolism (VTE). We examined the difference in the frequency of primary antiphospholipid antibody syndrome (PAPS) in VTE patients according to their BMI. Design and Methods: We included 998 VTE patients treated at our institution between 2009 and 2011 in a retrospective data analysis. Thrombophilia screening including evaluation for APS (lupus anticoagulant, anti‐cardiolipin, and anti‐B2‐glycoprotein‐I IgG and IgM antibodies) was performed in all patients. Results: PAPS was diagnosed in 6.8% (24/355) of normal weight (BMI < 24 kg/m²) VTE patients, in 11.1% (50/452) of overweight (BMI 25–30 kg/m²) VTE patients, and in 15.7% (30/191) of obese (BMI > 31 kg/m²) VTE patients. The difference of PAPS occurrence between these groups was statistically significant (P = 0.001). PAPS patients demonstrated higher fibrinogen levels as compared to non‐PAPS patients (median 416.0 md/dl vs. 352.0 mg/dl, P = 0.001). Furthermore, fibrinogen levels increased significantly according to the body weight of patients (median normal weight patients 330.0 mg/dl vs. overweight patients 359.0 mg/dl vs. obese patients 415.0 mg/dl, P = 0.001). Conclusion: PAPS seems to be more frequent in overweight and obese patients. As PAPS patients showed significantly higher fibrinogen levels and as fibrinogen levels increased significantly according to the body weight of patients, an elevated inflammatory state in overweight and obese patients as a reason for the increased PAPS occurrence can be assumed.     

Venous thromboembolism GWAS reported genetic makeup and the hallmarks of cancer: Linkage to ovarian tumour behaviour

Venous thromboembolism (VTE) is a common cardiovascular disease thought to be the outcome of an intricate interplay between acquired and inherited factors that act together to modify disease risk. Over the years, several single-nucleotide polymorphisms (SNPs) in candidate genes have been associated with disease risk, including F5 rs6025, F2 rs1799963, FGG rs2066865, ABO genetic variants, among others less common. More recently, genome-wide association studies (GWAS) have contributed to the identification of novel VTE-associated SNPs, some of them located in novel genes with no clear role in the haemostatic system, such as SLC44A2 rs2288904 and TSPAN15 rs78707713. Given the existence of a tight relationship between VTE and cancer, with both pathologies sharing biological pathways that allow one to promote the other, these SNPs constitute potential prognostic and predictive biomarkers currently needed for better management of cancer patients. Among solid tumours, ovarian cancer (OC) is one of the most frequently associated with VTE. Indeed, haemostatic components might have a significant impact in OC progression, and therefore, the clinical and biological implications of VTE-associated SNPs should be assessed in patients with this neoplasia.     

Endogenous oestrogens and breast cancer risk in premenopausal and postmenopausal women

Breast cancer risk is strongly related to several reproductive and hormonal factors, but the nature of the effects of endogenous oestrogens has been difficult to establish. Data are now available from several large prospective studies with biobanks of stored serum, enabling better characterization of the associations of endogenous oestrogens, and other endogenous hormones, with breast cancer risk. In postmenopausal women, relatively high serum concentrations of oestradiol are associated with a more than twofold increase in the risk for breast cancer, and this probably explains the increase in risk in obese postmenopausal women. In premenopausal women the data available on oestrogens are more limited and difficult to interpret due to the large variations in endogenous oestrogens during the menstrual cycle, but are compatible with a positive association between oestradiol and breast cancer risk. There is also evidence that breast cancer risk is positively associated with androgens, prolactin and insulin-like growth factor-I. Further data are required, with better assays and repeat measures, to provide more accurate estimates of risk and to clarify the role of oestrogens in premenopausal women and the roles of other endogenous hormones.     

Antithrombotic therapy in patients with known risk factors for thromboembolism

In about 50% of the cases of spontaneous deep vein thrombosis a congenital deficiency of an inhibitor of coagulation or an insufficient fibrinolytic mechanism can be detected. In arterial thromboembolism a connection with hyperactive platelets or with a diminished availability of tissue plasminogen activator can be found in about 70%. However, in these cases the defect which provokes thrombosis is mostly acquired and is connected with hyperlipidemia and/or with atherosclerotic alterations of the vessel wall. A study on patients with thromboembolic tendency and detectable risk factors was carried out. A total of 470 patients could be observed for 2 years under an adequate antithrombotic prophylaxis. The occurrence of thromboembolic episodes 2 years prior to prophylaxis and 2 years under prophylaxis was compared. In venous cases thrombosis could be controlled almost completely by coumarins when the underlying cause was a deficient plasmatic inhibitor. In patients with diminished fibrinolysis there was only a partial effect of oral anticoagulants. A better result could be obtained when pentosan polysulfate was administered. In arterial thromboembolism the results of prophylaxis were less convincing. The efficacy of ASA in patients with an increased platelet function was only moderate. In addition, ASA hat to be discontinued in about 20% of the patients because of gastrointestinal problems. Pentosan polysulfate in patients with a diminished fibrinolytic capacity had a fairly good effect and resulted in a 60% reduction of thromboembolic manifestations. It is shown that an exact diagnosis of the underlying deficiency which is likely to cause thrombosis can also improve the efficacy and the specificity of prophylaxis.     

Prospective breast cancer risk factors prediction in Saudi women

Women's health is affected by breast cancer worldwide and Saudi Arabia (SA) is no exception. Malignancy has enormous consequences for social, psychological and public health. The aim of this study was to examine the risk factors for Saudi women from breast cancer using logistic regression models. In 135 patient cases for different stages of breast cancer was used to study case management, 270 healthy women from King Abd Alla Medical City, Mecca, SA were taken to predict the probability of women developing breast cancer, logistic regression was analyzed taking factors such as age, marital status, family history, parity, age at first full-term pregnancy, menopausal status, body mass index (BMI) and breast feeding. The logistic regression model showed that there are important risk factors (age, marital status, family history, parity, age at first full-term pregnancy, menopausal status, body mass index, and breast feeding) in development of breast cancer. Fewer cases were observed in unmarried women, age ≤30, BMI ≤20. In contrast, more cases were found with women age 41–50 married, BMI > 30, a smaller number of children, not breast feeding, age of first pregnancy ≥30, menopausal status age at 46–50. Based on our data there is role of risk factors in developing breast cancer, less BMI, the increase number of children, breast feeding, which are playing as protective factor for breast cancer.     

INSERM-FNCLCC collective expertise. Recommendations for medical management of women with genetic risk of developing breast and/or ovarian cancer

BACKGROUND: Almost 10% of breast and ovarian cancer are inherited, and the majority are linked to BRCA1 and BRCA2 germline mutations. Despite the uncertainty in the management of women gene carriers, consensus guidelines were defined to assist practitioners', and patients' decisions about the health care decisions to be made. METHODOLOGY: The Ad Hoc Committee consisted of 14 experts designated by the French National Institute for Health and Medical Research. They all attended eleven workshops at which a systematic analytical review of more than 3500 articles was carried out. Five additional experts critically analysed the first version of the report. CRITERIA AND DECISION PROCESS: Two thresholds were defined on a probability scale giving the risk of developing breast or ovarian cancer, to serve as a means of deciding as whether an intervention is worthwhile. The first threshold is that above which an intervention can be envisaged or recommended; the second is that under which an intervention can be ruled out; between the two, the decision has to be made on a each by case basis. STRATEGIES ANALYZED: About breast cancer: 1) hormonal interventions; 2) primary prevention (diet, family planning and chemoprevention); 3) screening (breast self-examination, clinician breast examination, tumor markers, imaging); 4) prophylactic mastectomy. About ovarian cancer: 1) hormonal stimulation; 2) screening (clinical screening, ultrasound and tumor markers); 3) prophylactic oophorectomy. MAIN CONCLUSIONS: With each strategy the following points were dealt with; the information to be delivered to the Consultant, the procedure and the indications. In addition, the Committee's opinion about BRCA1 and BRCA2 mutation screening is that population-based or even large scale implementation are not justified. Although no scientific evidence is available, the Committee feels that specific management is indispensable and advocates the use of defined and evaluated procedures, and involvement in clinical trials.     

Association of gene polymorphisms in prolactin and its receptor with breast cancer risk in Taiwanese women

Given the essential role of prolactin (PRL) and its receptor (PRLR) in breast tumorigenesis, we investigated whether single nucleotide polymorphisms (SNPs) in the PRL and PRLR genes were associated with breast cancer in Taiwanese women. A total of 160 breast cancer patients and 336 unrelated control Taiwanese women were enrolled in this study. Three SNPs (rs1341238, rs2244502 and rs3756824) in the PRL gene and one SNP (rs10941235) in the PRLR gene were genotyped using allele-specific polymerase chain reaction and DNA sequencing. We showed that the PRLR SNP rs10941235 was associated with breast cancer (P < 0.05) and its genotype frequencies in the breast cancer group were significantly associated (P < 0.05) with the levels of cancer antigen 15-3, a serum biomarker of breast cancer. The PRL SNP rs3756824 was significantly associated with breast cancer metastasis (P < 0.05). These findings suggest that the polymorphism rs10941235 in the PRLR gene is associated with breast cancer and cancer antigen 15-3 levels in Taiwanese women.