Enhancement by factor V Leiden mutation of risk of deep-vein thrombosis associated with oral contraceptives containing a third-generation progestagen

Risk of nonfatal venous thromboembolism with oral contraceptives containing norgestimate or desogestrel compared with oral contraceptives containing levonorgestrel

CONTEXT

Previous studies have reported that users of the "third-generation" oral contraceptives (OCs) containing the progestins gestodene and desogestrel have about twice the risk for venous thromboembolism (VTE) compared to users of older OCs containing levonorgestrel. Estimates of the risk for VTE among users of norgestimate-containing OCs compared to other OCs, however, are lacking.

OBJECTIVE

The purpose of this study is to obtain quantitative information on the risk of nonfatal VTE in women using OCs containing either norgestimate or desogestrel in comparison with women taking OCs containing levonorgestrel.

DESIGN, SETTING AND PARTICIPANTS

Based on information from PharMetrics, a United States-based company that collects and records information on claims paid by managed care plans, we used a nested case-control study design to estimate relative risks of nonfatal VTE among 15- to 39-year-old current users of OCs containing norgestimate with 35 microg of ethinyl estradiol (EE), desogestrel with 30 microg of EE or levonorgestrel with 30 microg of EE, both monophasic and triphasic preparations, during the period January 2000 to March 2005. Cases were women with a well-documented VTE of uncertain origin that was diagnosed in current users of a study drug. Up to four controls were closely matched to each case by age and calendar time, and odds ratios (ORs) were calculated using conditional logistic regression comparing the risk of VTE among users of the three contraceptives. We also estimated and compared the incidence rates for all three OCs.

RESULTS

Based on 281 newly diagnosed idiopathic cases of VTE and 1055 controls, we found that the adjusted ORs for nonfatal VTE comparing norgestimate- or desogestrel-containing OC users to users of levonorgestrel-containing OCs were 1.1 [95% confidence interval (CI), 0.8-1.6] and 1.7 (95% CI, 1.1-2.4), respectively. The incidence rates of VTE were 30.6 (95% CI, 25.5-36.5), 53.5 (95% CI, 42.9-66.0) and 27.1 (95% CI, 21.1-34.3) per 100,000 woman-years for users of norgestimate-, desogestrel- and levonorgestrel-containing OCs, respectively. The incidence rate ratios for norgestimate-containing OCs compared to levonorgestrel-containing OCs and desogestrel-containing OCs compared to levonorgestrel-containing OCs were 1.1 (95% CI, 0.8-1.5) and 2.0 (95% CI, 1.4-2.7), respectively.

CONCLUSIONS

The risk of nonfatal VTE among users of desogestrel-containing OCs is significantly elevated compared to that of levonorgestrel-containing OCs. The risk of VTE in users of norgestimate-containing OCs was closely similar to that of users of levonorgestrel-containing OCs.

[Hormone therapy, fertility and pregnancy in antiphospholipid syndrome]

Antiphospholipid syndrome (APS) carries a risk of thrombosis and infertility. Consequently the use of any type of hormone therapy and pregnancy in APS requires special considerations. The present article provides a broad review of all these issues. The use of contraception, hormone replacement therapy and selective estrogen receptor modulators in APS are described. In vitro fertilization/embryo transfer and ovarian induction in these patients are reviewed. Lastly, the possible fetal and maternal complications that can occur during pregnancy are described and, based on the literature, recommendations for the management of pregnancy in women with APS are provided.

Does use of hormonal contraceptives among women with thrombogenic mutations increase their risk of venous thromboembolism? A systematic review

Because use of combined oral contraceptives (COCs) confers some risk of venous thromboembolism (VTE), there is concern that this effect may be greater among women with thrombogenic mutations. We searched the MEDLINE and EMBASE databases for all articles published from January 1966 through September 2004 for evidence relevant to hormonal contraception and thrombogenic mutations. Of 301 articles identified by the search strategy, 16 evaluated COCs, and no studies were found for other hormonal methods. We used standard abstract forms and grading systems to summarize and assess the quality of the evidence. A total of 10 studies together provided "good" evidence of a greater risk of VTE (risk ratios of 1.3-25.1) and cerebral vein or cerebral sinus thrombosis among COC users with factor V Leiden mutation when compared with nonusers who have the mutation. The evidence for prothrombin and other thrombogenic mutations was not as strong as for factor V Leiden mutation. It is unclear whether the type of COC or duration of use modifies the risk of VTE among women with thrombogenic mutations.

Thrombosis Secondary to Medroxyprogesterone in Patient at Risk for Thromboembolism

Objective:

To report a case in which a young woman receiving medroxyprogesterone acetate injections developed deep vein thrombosis (DVT) after prolonged travel.

Case Summary:

An obese 27-year-old African American woman who had been receiving medroxyprogesterone acetate injections 150 mg intramuscularly every 3 months for 6 years experienced DVT after a 56-hour car ride. The patient's known risk factors for DVT included immobility, obesity (140 kg), and medroxyprogesterone acetate therapy. Family and personal history for thrombotic events were denied. Tests were performed after detection of the DVT to assess the patient for anticoagulation defects; results revealed an unidentified underlying protein S deficiency. All other test results were within normal limits.

Discussion:

Based on the Naranjo probability scale, it is possible that the DVT experienced by our patient was due to medroxyprogesterone acetate. Although she did have other risk factors for DVT, her underlying protein S deficiency was diagnosed after the thrombosis. Literature describing the relationship between the injectable form of contraception and thrombosis is limited. Therefore, this report reviews protein S deficiency, the relationship between oral contraceptives (OCs) and thrombosis, the influence of immobility on thrombosis development, and the clinical implications of evaluating patients for underlying inherited clotting abnormalities before initiating OCs.

Conclusions:

When considering whether to prescribe contraceptives, clinicians should assess the patient's risk factors for thrombosis, such as family or personal history. Although generally not recommended, prescreening tests may be considered if there is a positive family or personal history.

Venous thromboembolism: disease burden, outcomes and risk factors

The epidemiology of venous thromboembolism (VTE) in the community has important implications for VTE prevention and management. This review describes the disease burden (incidence), outcomes (survival, recurrence and complications) and risk factors for deep vein thrombosis and pulmonary embolism occurring in the community. Recent comprehensive studies of the epidemiology of VTE that reported the racial demography and included the full spectrum of disease occurring within a well-defined geographic area over time, separated by event type, incident vs. recurrent event and level of diagnostic certainty, were reviewed. Studies of VTE outcomes had to include a relevant duration of follow-up. VTE incidence among whites of European origin exceeded 1 per 1000; the incidence among persons of African and Asian origin may be higher and lower, respectively. VTE incidence over recent time remains unchanged. Survival after VTE is worse than expected, especially for pulmonary embolism. Thirty percent of patients develop VTE recurrence and venous stasis syndrome. Exposures can identify populations at risk but have a low predictive value for the individual. An acquired or familial thrombophilia may predict the subset of exposed persons who actually develop symptomatic VTE. In conclusion, VTE is a common, lethal disease that recurs frequently and causes serious long-term complications. To improve survival and prevent complications, VTE occurrence must be reduced. Better individual risk stratification is needed in order to modify exposures and target primary and secondary prophylaxis to the person who would benefit most.

Gene-environment interactions in human diseases

Studies of gene-environment interactions aim to describe how genetic and environmental factors jointly influence the risk of developing a human disease. Gene-environment interactions can be described by using several models, which take into account the various ways in which genetic effects can be modified by environmental exposures, the number of levels of these exposures and the model on which the genetic effects are based. Choice of study design, sample size and genotyping technology influence the analysis and interpretation of observed gene-environment interactions. Current systems for reporting epidemiological studies make it difficult to assess whether the observed interactions are reproducible, so suggestions are made for improvements in this area.

Factor V Leiden, prothrombin 20210A and the risk of venous thrombosis among cancer patients

Cancer patients have an increased risk of venous thrombosis (VT). The association of factor V Leiden (FVL) and the prothrombin 20210A variant with VT in cancer patients is not established. We genotyped 101 cancer patients with VT and 101 cancer patients without VT for these polymorphisms. Five cases and three controls were heterozygous for FVL, yielding an odds ratio of 1.7 (95% confidence interval (CI) 0.3-10.7). Five cases and no controls were heterozygous for prothrombin 20210A, for an odds ratio of 6.7 (95% CI 0.9-infinity). Prothrombin 20210A may be associated with VT risk among cancer patients.

Pronto ThromboRisk--a novel primer-extension ELISA based assay for the detection of mutations associated with increased risk for thrombophilia

The role of inherited thrombophilias in the pathogenesis of thrombosis, and their relation to thromboembolic events and pregnancy complications, has escalated the demand for molecular testing. We employed the new Pronto ThromboRisk kit (Pronto Diagnostics Ltd., Rehovot, Israel), which is based on a novel primer-extension ELISA assay, for the simultaneous detection of three genetic mutations. These are Factor V Leiden G1691A (R506Q), prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T, which are known to have increased incidence in patients with thromboembolic events and pregnancy complications. We examined 284 randomly selected patient samples from the special coagulation hospital laboratory. The results using the new assay were compared to those obtained by routinely employed conventional molecular techniques. The ThromboRisk kit provided identical results with no false-negative results and with a high specificity of over 99% for all three mutations. We conclude that the Pronto ThromboRisk kit allows fast, precise, and reliable testing for the three genetic mutations. The assay is easy to perform and provides a useful tool for screening high risk populations, such as patients with a personal or family history of venous thromboembolism, women with pregnancy complications, or users of oral contraceptives.

Genetic thrombophilias and preeclampsia: a meta-analysis

OBJECTIVE

To assess the relationship between the factor V Leiden (1691 G-A) single nucleotide polymorphism (SNP), the methylene tetrahydrofolate reductase (MTHFR) 677 C-T SNP, and the prothrombin 20210 G-A SNP and the risk of preeclampsia, by conducting a meta-analysis of all case-control studies with data on these polymorphisms and the risk of preeclampsia.

DATA SOURCES

MEDLINE (1966 to November 2002), EMBASE (1980 to November 2002). Search terms included "preeclampsia," "thrombophilia," "factor V Leiden," "protein C," "MTHFR," "methylenetetrahydrofolate reductase," "homocysteine," and "prothrombin gene 20210."

METHODS OF STUDY SELECTION

Case-control studies of genetic thrombophilias and preeclampsia were included.

TABULATION, INTEGRATION, AND RESULTS

We identified 349 titles and reviewed 47 articles for inclusion and exclusion criteria. Thirty-one studies with 7,522 patients were included in the meta-analysis. Data from patients characterized as having severe preeclampsia were extracted and analyzed separately. The pooled odds ratio (OR) for the association of factor V Leiden and all cases of preeclampsia was 1.81 (95% confidence interval [CI] 1.14-2.87) and 2.24 (95% CI 1.28-3.94) for cases of severe preeclampsia. The pooled OR for the MTHFR 677 TT genotype and all preeclampsia was 1.01 (95% CI 0.79-1.29) and 1.38 (95% CI 0.93-2.06) for severe preeclampsia. The OR for the prothrombin 20210 polymorphism and all preeclampsia was 1.37 (95% CI 0.72-2.57) and 1.98 (.94-4.17) for severe preeclampsia.

CONCLUSION

This meta-analysis suggests that the factor V Leiden SNP is associated with an increased risk of preeclampsia. Further studies are warranted to determine whether subgroups of high-risk women should be screened for this mutation.

Differential effects of 17beta-estradiol, conjugated equine estrogen, and raloxifene on mRNA expression, aggregation, and secretion in platelets

Changes in platelet functions could contribute to thrombotic risk associated with estrogen treatments. This study was designed to test the hypothesis that three clinically relevant estrogenic treatments affect platelet function comparably. Adult female pigs were ovariectomized and randomized to either no treatment or treatment with oral 17 beta-estradiol (2 mg/day), conjugated equine estrogen (0.625 mg/day), or raloxifene (60 mg/day) for 4 wk. Platelet turnover, aggregation, and secretion were assessed before and after treatment. Platelet turnover and mRNA increased significantly only in pigs treated with 17 beta-estradiol. Expression of estrogen receptors increased with ovariectomy and decreased with all treatments. Platelet aggregation and secretion of ATP, platelet-derived growth factor, and matrix metalloproteinase-2 increased with ovariectomy. All treatments reduced both aggregation and secretion. Expression of mRNA for constitutive endothelial nitric oxide synthase (eNOS), but not eNOS protein, increased with ovariectomy. Only eNOS mRNA decreased with all treatments, but only treatment with 17 beta-estradiol increased secretion of nitric oxide from intact platelets. Platelets from 17 beta-estradiol-treated animals caused relaxation of coronary arteries, which was sensitive to inhibition of nitric oxide. Although three different estrogenic treatments reversed increases in platelet aggregation caused by ovariectomy, only 17 beta-estradiol increased platelet RNA and release of platelet-derived nitric oxide. These differences reflect transcriptional and posttranscriptional regulation of protein synthesis in bone marrow megakaryocytes and circulating platelets.

Potential impact of oral contraceptive choice on myocardial infarction mortality and deep vein thrombosis

OBJECTIVES

To summarise the epidemiological evidence on the relationship between second- (OC2) and third-generation (OC3) oral contraceptives (OC) and the mortality associated with deep vein thrombosis (DVT) and myocardial infarction (MI), and to extrapolate and balance the evidence for these risks to the population of French OC users.

METHODS

All studies published on the risk of MI during OC2 and OC3 use were analysed. For DVT the Committee for Proprietary Medicinal Products public assessment report published in 2001 and more recent studies published on this topic were used. The estimates of odds ratios (OR) for risk of death from DVT or MI were extracted from the published manuscripts. ORs were used to calculate the aetiological fraction of risk for death from DVT and MI in the population; the relative impact of OC3 compared to OC2 use was expressed as an excess risk of death overall and by age group for French women.

RESULTS

Compared with OC2, the use of OC3 would prevent a maximum of 24 deaths from MI per year and induce a maximum of 16 deaths. Conversely, OC3 would induce 282-940 excess cases of DVT per year, resulting in 28-94 pulmonary embolisms and 3-19 deaths in the 4.7 million French OC users.

CONCLUSION

Balancing the evidence, it is difficult to conclude that the overall cardiovascular risk is significantly lower for either of the two OC schemes.

Venous Thrombosis: The Role of Genes, Environment, and Behavior

Over the last decade we have witnessed an avalanche of newly identified risk factors for venous thrombosis. This has advanced our knowledge of its etiology, because more determinants have been described and because the underlying concepts have received a new and broader understanding.

Venous thrombosis is a common multicausal disease occurring as the result of interacting genetic, environmental and behavioral risk factors. Some of these have been known since medieval times, such as the increased risk of thrombosis during immobilization in pregnancy and after childbirth (although retained milk of the breast-feeding mother was seen as the primary cause for the latter). Pregnancy and puerperium still cause thrombosis, as do exogenous hormones in oral contraceptives and hormonal replacement therapy. Furthermore, the immobilization in the puerperium of the old days translates directly to situations of immobilization in current times, such as prolonged travel in airplanes or excessive electronic gaming.

While pedigrees with abundant thrombosis were observed in the early 1900s, the first cause of heritable thrombophilia (antithrombin deficiency) was discovered in 1965, with the subsequent identification of deficiencies of protein C and protein S in the early 1980s. These were uncommon and strong risk factors, whereas the more recently discovered genetic variants are common and weak, and cause disease only in the presence of other factors.

Venous thrombosis: the role of genes, environment, and behavior

Over the last decade we have witnessed an avalanche of newly identified risk factors for venous thrombosis. This has advanced our knowledge of its etiology, because more determinants have been described and because the underlying concepts have received a new and broader understanding. Venous thrombosis is a common multicausal disease occurring as the result of interacting genetic, environmental and behavioral risk factors. Some of these have been known since medieval times, such as the increased risk of thrombosis during immobilization in pregnancy and after childbirth (although retained milk of the breast-feeding mother was seen as the primary cause for the latter). Pregnancy and puerperium still cause thrombosis, as do exogenous hormones in oral contraceptives and hormonal replacement therapy. Furthermore, the immobilization in the puerperium of the old days translates directly to situations of immobilization in current times, such as prolonged travel in airplanes or excessive electronic gaming. While pedigrees with abundant thrombosis were observed in the early 1900s, the first cause of heritable thrombophilia (antithrombin deficiency) was discovered in 1965, with the subsequent identification of deficiencies of protein C and protein S in the early 1980s. These were uncommon and strong risk factors, whereas the more recently discovered genetic variants are common and weak, and cause disease only in the presence of other factors.

Evidence-based risk factors for postoperative deep vein thrombosis

BACKGROUND

Deep vein thrombosis (DVT) is a common postoperative complication that is associated with significant morbidity and mortality. Thromboprophylaxis has been shown to be underused. In the absence of prophylaxis, rates as high as 50% have been reported following orthopaedic surgery, and 25% following general surgery. Many risk factors have been suggested but there is often little evidence to support these claims.

METHODS

A systematic review was performed to determine the evidence base behind each suggested risk factor, and, where sufficient data were available, a random-effects meta-analysis was performed.

RESULTS

There is evidence to support a significant association between increased age, obesity, a past history of thromboembolism, varicose veins, the oral contraceptive pill, malignancy, Factor V Leiden gene mutation, general anaesthesia and orthopaedic surgery, with higher rates of postoperative DVT, although there remain some variables within the study designs that may lead to overestimation of effect. There is no evidence to support the suggested risk factors of hormone replacement therapy, gender, ethnicity or race, chemotherapy, other thrombophilias, cardiovascular factors, smoking and blood type.

CONCLUSIONS

An accurate knowledge of evidence-based risk factors is important in predicting and preventing postoperative DVT, and can be incorporated into a decision support system for appropriate thromboprophylaxis use.

Epidemiology of acute deep vein thrombosis

Although the factors leading to venous thrombosis have been known for over a century, Virchow's initial model of thrombosis has been extensively refined. Activated coagulation is now recognized to be of primary importance in venous thrombogenesis; the concept of venous injury has been expanded to include molecular changes in the endothelium; and stasis has been redefined as a largely permissive factor. Furthermore, it is now clear that venous thrombi undergo a dynamic evolution beginning early after their formation. The natural history of acute deep venous thrombosis (DVT) is a balance between recurrent thrombotic events and processes that restore the venous lumen, both of which have important implications for the development of complications. Although pulmonary embolism (PE) is clearly the most life threatening complication of acute DVT, the long term socio-economic consequences of the post thrombotic syndrome (PTS) have perhaps been underemphasized in clinical trials. The development of post-thrombotic manifestations is related to both residual venous obstruction and valvular incompetence. Recognition of the factors contributing to a poor outcome, including recurrent thrombotic events, the rate of recanalization, the global extent of venous reflux, and the anatomic distribution of reflux and obstruction is important, as there may be therapeutic alternatives to alter the natural history of acute DVT. The treatment alternatives will continue to expand with the introduction of new therapeutic drugs, for both systemic and catheter-directed therapy, and mechanical thrombectomy devices. The primary care physician is challenged with the task of correctly evaluating deep vein thrombosis and providing his patient with access to the most clinically appropriate, and cost-effective, diagnostic and management options available. This article will review the epidemiology of DVT, its risk factors and major complications.

Inherited risk of thrombosis of the fetus and intrauterine fetal death

OBJECTIVE

To test the hypothesis that abnormal placentation resulting in intrauterine fetal death (IUFD) is associated with coagulation abnormalities in the fetus.

STUDY DESIGN

We analyzed fetal DNA from umbilical cords from 139 pregnancies complicated by intrauterine fetal death during 1994-1998 (cases). Fetal DNA was tested for the presence of factor V Leiden and prothrombin G20210A mutations. The prevalence of these thrombophilic mutations among cases were compared with the prevalence in a historic control group.

RESULTS

Overall, a higher prevalence of fetal genetic risk factors was found in cases (9.8%) as compared to fetuses born from an uncomplicated pregnancy (2%, odds ratio 4.8, 95% CI 1.1-22). Second trimester intrauterine fetal death occurred more frequently in cases with the factor V Leiden mutation as compared with the control group (8/64 versus 0/92). For intrauterine fetal death and factor V Leiden a high risk was found concerning abruption placentae (odds ratio 7.6, 95% CI 1.5-37).

CONCLUSION

The prevalence of fetal genetic risk factors associated with an increased risk for thrombosis was higher in pregnancies complicated by intrauterine fetal death suggesting an important role of abnormal coagulation in placentation.

Hormones and pregnancy: thromboembolic risks for women

During their lifetimes, women face several unique situations with an increased risk of venous thromboembolism (VTE). Doctors in a variety of specialties must advise women on the risks of oral contraceptives (OC), hormone replacement or pregnancy. Modern 'low dose' OC are associated with a three to sixfold increased relative risk of VTE. Hormone replacement and selective oestrogen receptor modulators confer a similar two to fourfold increase in thrombotic risk. However, because the baseline incidence of thrombosis is higher in older postmenopausal women, the absolute risk is higher than in younger OC users. The risk of venous thrombosis is six to 10-fold higher during pregnancy than in non-pregnant women of similar age. Thrombophilic disorders increase the thrombotic risk of OC, hormone replacement and pregnancy, especially in women with homozygous or combined defects. This review focuses on recent data estimating the thrombotic risk of hormonal therapies and pregnancy in women with and without other thrombotic risk factors.

Pharmacogenetic aspects of the use of oral contraceptives and the risk of thrombosis

Oral contraceptives are currently used by more than 100 million women in developed countries and are a highly efficacious method to prevent undesired pregnancies. However, oral contraceptives are associated with an increased risk of venous and arterial thrombosis, through changes in blood coagulation and fibrinolysis. In order to reduce such complications, the composition of oral contraceptives has changed over the past decades, both for the dose of oestrogen and the type of progestagen. However, the risk for venous thromboembolism remains, particularly for women who are carriers of inherited thrombophilia. In these women, prescription of oral contraceptives should be carried out on an individual basis. This review illustrates the risk of thrombosis, particularly venous thromboembolism, associated with the use of oral contraceptives, underlines the crucial role of the interaction of these drugs with other risk factors for the disease, and gives suggestions on the utility of thrombophilia screening before prescription.

Incidence of venous thromboembolism in young Swedish women and possibly preventable cases among combined oral contraceptive users

BACKGROUND

We wanted to study the incidence of venous thromboembolism (VTE), acquired risk factors of VTE and preventable cases among users of combined oral contraceptives (COCs).

METHODS

All women aged 15-44 years, (n = 24 373) living in the county of Jämtland, Sweden, between 1991 and 2000, constituted the study base in a retrospective case-reference study. Women with VTE were identified through hospital registers and interviewed by telephone. The utilization of COCs according to age was obtained from a prospective prescription database, and data from national health databases were used.

RESULTS

Of 88 women with first-time VTE, 43 (49%) were COC users and 13 (15%) were pregnant. All women had at least one known risk factor, and 51 (58%) women had combinations of risk factors. The total incidence rate of VTE per 100,000 women-years for all women were 36 (29-44), for nonusers 19 (12-25) for women using third generation COCs 115 (67-184), for women using other COCs 60 (37-83), and for women during pregnancy and postpartum 103 (55-177). Of the total 244,000 women-years represented, COC users constituted 24%, pregnant women 5%, and women with other acquired risk factors 5%. The corresponding incidence rates after excluding VTE cases with other acquired risk factors were 10 (6-14), 1.2 (0.14-4.4), 64 (29-121), 27 (13-48), and 59 (24-121), per 100,000 women-years. In 11 (26%) of the COC-related VTE cases, there were relative contraindications for use of COCs or lack of thromboprophylaxis in relation to surgery. CONCLUSION. We found a very low incidence of idiopathic VTE among young non-OC users. The incidence of VTE during pregnancy was only slightly higher than during COC use. It was considered that a significant part of COC-related VTE might have been avoided.

Pulmonary embolism associated with combined oral contraceptives: reporting incidences and potential risk factors for a fatal outcome

BACKGROUND

It is established that combined oral contraceptive (COC) treatment increases the risk of a pulmonary embolism (PE), but specific risk factors for a fatal outcome from a PE remain to be determined. This study aimed to identify such risk factors, and to calculate the reporting rates of fatal and non-fatal PE.

METHODS

Cases of suspected PE during treatment with COCs reported to the Swedish Adverse Drug Reactions Advisory Committee (SADRAC) between 1965 and 2001 were included. Medical records were scrutinized for potential risk factors for a venous thromboembolism (VTE). Annual sales data were obtained from the National Corporation of Pharmacies.

RESULTS

A total of 248 cases of a suspected PE were reported; 207 non-fatal and 41 fatal. A VTE was verified in all fatal, and in 83.5% of non-fatal cases. The presence of nausea or abdominal pain, an age >35 years, concomitant treatment with other drugs which may increase the VTE risk, vein or lymph vessel malformation, and a deep vein thrombosis above the knee level were positively associated with a fatal outcome. Chest pain and previous COC use were negatively associated with a fatal outcome. The reporting rate of a PE with a verified VTE was 1.72 (95% confidence interval 1.47-2.00) cases per 100 000 treatment years, and of a fatal PE 0.25 (95% confidence interval 0.16-0.37) cases per 100 000 treatment years.

CONCLUSION

Several specific potential risk factors for a fatal outcome from a COC-induced PE were identified. Recognition of these in combination with a high suspicion of VTE in COC users may reduce the risk of a fatal outcome.

Safety concerns and health benefits associated with oral contraception

Since the introduction of hormonal contraceptives in the 1960s, there have been a variety of both health benefits and safety concerns attributed to their use. In most instances, the noncontraceptive benefits of oral contraceptives (OCs) outweigh the potential cardiovascular risks. In fact, the probability of a patient experiencing a cardiovascular event while taking a low-dose OC is very low. However, smoking, hypertension, obesity, and diabetes are risk factors that must be taken into account when prescribing OCs. The neoplastic effects of hormonal contraceptives have been extensively studied, and recent meta-analyses indicate that there is a reduction in the risk of endometrial and ovarian cancer, a possible small increase in the risk for breast and cervical cancer, and an increased risk of liver cancer. Finally, many women will experience noncontraceptive health benefits with OCs that expand far beyond pregnancy prevention. Some of these benefits include reduction in menstrual-related symptoms, fewer ectopic pregnancies, a possible increase in bone density, and possible protection against pelvic inflammatory disease.

Enhancing oral contraceptive success: the potential of new formulations

Reductions in oral contraceptive (OC) estrogen dose and the development of new progestins have resulted in formulations that maintain acceptable cycle control while improving safety. However, the potential safety benefits of low-estrogen doses may be offset by less acceptable cycle control. These observations have led to the development of 2 triphasic OC formulations containing norgestimate and desogestrel in combination with 25 microg ethinyl estradiol (EE). Both of these 25-microg EE triphasic OCs balance fewer estrogen-related side effects with good cycle control comparable to OCs containing higher estrogen doses. However, questions remain about the risk of venous thromboembolism associated with OCs containing desogestrel. A new monophasic 30-microg EE OC contains drospirenone, a spironolactone analogue with which there is limited experience. Although initial data with this OC are intriguing, product labeling highlights safety issues related to its antimineralocorticoid effects and the potential for hyperkalemia. Further experience with this formulation will determine its role in contraceptive practice.

Performance of a novel test to quantify activated protein C resistance in women with a history of pre-eclampsia

OBJECTIVE

We determined the performance of a functional test for activated protein C (APC) resistance in formerly pre-eclamptic women and matched controls.

STUDY DESIGN

In our university medical center, we assessed the response to APC in plasma in 118 formerly pre-eclamptic women and in 57 healthy controls, we measured plasma levels of thrombophilic factors and we performed statistical analysis.

RESULTS

The incidence of APC resistance was significantly higher in formerly pre-eclamptics than in controls. Formerly APC resistant pre-eclamptics more often experienced intra-uterine growth restriction (IUGR) than their non-APC resistant counterparts.

CONCLUSION

APC resistance determined by this functional test is present in a large subgroup of formerly pre-eclamptics. A higher incidence of IUGR in this group suggests a more severe course of the experienced pregnancy complications. Additional study is needed to determine whether this test is sensitive in predicting recurrence of pre-eclampsia or IUGR.

Predictors of left ventricular thrombus formation in patients with dilated cardiomyopathy: role of activated protein C resistance

OBJECTIVES

The aim of this study was to investigate the association between left ventricular thrombus formation and natural anticoagulant systems including the protein C, protein S and antithrombin in patients with dilated cardiomyopathy.

MATERIALS AND METHODS

Sixty patients with dilated cardiomyopathy who met the inclusion criteria were included in the study. Patients were divided into two groups: group I consisted of 22 patients with left ventricular thrombus and group II consisted of 38 patients without left ventricular thrombus. Our main inclusion criteria were ejection fraction </= 35% and left ventricular end-diastolic diameter >/= 6.0 cm. These two groups were compared for clinical and hematologic parameters (activated protein C resistance, protein S and antithrombin).

RESULTS

There were no statistically significant differences between patients with or without left ventricular thrombi with respect to left ventricular end-diastolic and end-systolic dimensions, ejection fraction, fractional shortening and left atrial diameter. There were no statistically significant differences between patients with and without left ventricular thrombus with respect to platelet count (252 +/- 64/mm3 x 10(3) compared with 260 +/- 74/mm3 x 10(3) respectively, P=0.68), prothrombin time (12.94 +/- 1.9 s compared with 12.86 +/- 1.3 s respectively, P=0.82), activated partial thromboplastin time (32 +/- 5 compared with 30 +/- 4 s respectively, P=0.32) and fibrinogen levels (36 +/- 9 mg/dl compared with 34 +/- 8 mg/dl respectively, P=0.41). None of the patients had protein S and antithrombin deficiency. Activated protein C resistance was found in 12 patients (12 out of 22, 54%) in group I and four patients (four out of 38, 9.5%) in group II (P < 0.01). It was also shown to be an independent predictor of left ventricular thrombus (P < 0.05).

CONCLUSION

Activated protein C resistance is found to be an independent predictor of left ventricular thrombus in patients with dilated cardiomyopathy who have ejection fractions less then 35% and left ventricular end-diastolic dimensions > 6.0 cm.

Safety of a New Oral Contraceptive Containing Drospirenone

New chemical entities must undergo rigorous, and preferably independent, safety and efficacy assessments before entry into the market. This is also true for oral contraceptives (OCs) given their extensive usage by healthy women and the safety concerns highlighted by the so-called 'third generation pill scare' in Europe a decade ago. This scare heightened patient and physician awareness of the increased risk of thromboembolic complications (mainly venous thromboembolism [VTE]) associated with OC use. Yasmin (ethinylestradiol 30 microg/drospirenone 3 mg [EE/DRSP]) is a novel OC that was demonstrated in clinical phase I-III studies to be highly effective in preventing pregnancy and to have a good safety profile. Nonetheless, clinical trials are not usually sufficiently powered to detect rare adverse events such as VTE to enable comparison with other OCs, which could allay fears and concerns about their inherent risks. Therefore, an extensive assessment of the VTE risk associated with EE/DRSP has been undertaken by reviewing data from the clinical development programme, postmarketing surveillance and spontaneous worldwide reporting, as well as information from other sources. Spontaneous worldwide reporting has revealed a VTE reporting rate of 5.1/100 000 women-years with EE/DRSP use. In contrast, 3-year interim results from a large, controlled, prospective postmarketing surveillance study suggest a VTE rate of 61/100 000 women-years for EE/DRSP, which is similar to the rates of 60/100 000 and 73/100 000 women-years for levonorgestrel-containing OCs and other OCs, respectively. When placed in context with potential biases and confounding factors that would inflate the perceived risk of VTEs with a novel OC, the VTE rate with EE/DRSP does not highlight any safety concerns. Furthermore, the risk of VTE with EE/DRSP or other OCs is far less than that associated with pregnancy and delivery (up to 800/100 000 women-years) or than other risks of daily living. Available data indicate that EE/DRSP is not associated with any increased risk of other serious adverse events such as hyperkalaemia, cardiac arrhythmia or birth defects. Nonetheless, caution should be exerted in prescribing EE/DRSP to women with conditions that predispose to hyperkalaemia.Overall, the safety data with EE/DRSP and other OCs indicate that these products have no negative impact on the risk of VTE (and other adverse events) in women who receive OCs for contraception.

Venous thrombosis and changes of hemostatic variables during cross-sex hormone treatment in transsexual people

The incidence of venous thrombosis associated with estrogen treatment in male-to-female (M-->F) transsexuals is considerably higher with administration of oral ethinyl estradiol (EE) than with transdermal (td) 17-beta-estradiol (E(2)). To find an explanation for the different thrombotic risks of oral EE and td E(2) use, we compared the effects of treatment of M-->F transsexuals with cyproterone acetate (CPA) only, and with CPA in combination with td E(2), oral EE, or oral E(2) on a number of hemostatic variables [activated protein C (APC) resistance and plasma levels of protein S, protein C, and prothombin], all of which are documented risk factors for venous thrombosis. APC resistance was determined by quantification of the effect of APC on the amount of thrombin generated during tissue factor-initiated coagulation; plasma levels of total and free protein S were determined by standard ELISA; and levels of prothrombin and protein C were determined with functional assays after complete activation of the zymogens with specific snake venom proteases. CPA-only, td-E(2)+CPA, or oral-E(2)+CPA treatment produced rather small effects on hemostatic variables, whereas oral EE treatment resulted in a large increase in APC resistance from 1.2 +/- 0.8 to 4.1 +/- 1 (P < 0.001), a moderate increase in plasma protein C (9%; P = 0.012), and a large decrease in both total and free plasma protein S (30%; P < 0.005). The large differential effect of oral EE and oral E(2) indicates that the prothrombotic effect of EE is due to its molecular structure rather than to a first-pass liver effect (which they share). Moreover, these differences may explain why M-->F transsexuals treated with oral EE are exposed to a higher thrombotic risk than transsexuals treated with td E(2). Testosterone administration to female-to-male transsexuals had an antithrombotic effect.

Estrogen-containing oral contraceptives are allowable in young women with factor V Leiden heterozygosity without a history of thrombosis

An 18-year-old woman without significant past medical and surgical history presents to discuss the safety and efficacy of oral contraceptives. She is sexually active and currently relying on condoms alone for birth control. Her cousin had a deep venous thrombosis (DVT) following a pregnancy. As part of the family screening, this patient was identified as a factor V Leiden heterozygote. The risks and benefits of initiating oral contraceptives are discussed.

Inherited and acquired risk factors for venous thromboembolic disease among women taking tamoxifen to prevent breast cancer

PURPOSE

Venous thromboembolism (VTE) is of particular concern in women receiving tamoxifen in a chemopreventive setting. We investigate the association between acquired and inherited risk factors for VTE in the International Breast Cancer Intervention Study (IBIS-I) trial of tamoxifen prophylaxis for women at increased risk of breast cancer.

METHODS

We used a nested case-control study design to investigate the role of tamoxifen and acquired risk factors in the risk of developing a VTE.

RESULTS

Tamoxifen was associated with a significantly increased risk of developing a major VTE (odds ratio [OR], 2.1; 95% CI, 1.1 to 4.1). Women who had surgery, immobilization, or fracture in the previous month had a greatly increased risk of developing a major VTE (OR, 4.7; 95% CI, 2.2 to 10.1). Prothrombin and factor V Leiden mutations were found exclusively among control women: factor V Leiden in eight of 159 control women (5.0%) and the prothrombin mutation in three control women (1.9%). Thirty-five women with a VTE and a blood sample were negative for these mutations. The upper one-sided 97.5% CI for the OR of having either mutation was 1.87. Being overweight, smoking, or taking hormone replacement therapy was not associated with VTE in this study, but the CIs were wide.

CONCLUSION

Tamoxifen and prior surgery, fracture, or immobilization were associated with a significantly increased risk of developing a VTE. Factor V Leiden and prothrombin mutations were not associated with thrombosis in this population.

Effect of second- and third-generation oral contraceptives on the protein C system in the absence or presence of the factor VLeiden mutation: a randomized trial

A plausible mechanism to explain thrombotic risk differences associated with the use of second- and third-generation oral contraceptives (OCs), particularly in carriers of factor V(Leiden), is still lacking. In a double-blind trial, 51 women without and 35 women with factor V(Leiden) were randomized to either a second- (30 microg ethinylestradiol/150 microg levonorgestrel) or third- (30 microg ethinylestradiol/150 microg desogestrel) generation OC. After 2 cycles of use and a wash-out of 2 cycles, the participants continued with the corresponding progestagen-only preparation. Hemostatic variables that probe the activity of the anticoagulant protein C system were determined. Compared with levonorgestrel, desogestrel-containing OCs significantly decreased protein S and increased activated protein C (APC) resistance in both groups. OCs with desogestrel had the most pronounced effects in carriers of factor V(Leiden). Progestagen-only preparations caused changes of anticoagulant parameters opposite to those of combined OCs, which in a number of cases were more pronounced with levonorgestrel. Our data show that progestagens in combined OCs counteract the thrombotic effect of the estrogen component. The higher thrombotic risk associated with third-generation OCs compared with second-generation OCs may be explained by the fact that desogestrel appeared less antithrombotic than levonorgestrel, especially in women with factor V(Leiden).

Genetics in rheumatoid arthritis

This chapter reviews the latest original research on the genetics of rheumatoid arthritis (RA), with a focus on its relevance for the clinical rheumatologist. The following questions will be dealt with in order to appreciate the recent progress in this field. * Why is a knowledge of genetics useful for an understanding of the pathogenesis of RA? * Is a knowledge of genetic risk factors relevant for day-to-day clinical practice? * What methods are used for identifying genetic risk factors? * Which genetic regions have been identified in susceptibility to RA? * What risk factors have been identified? * What are the future prospects and research agenda?

Comparative study of the effects of two once-a-month injectable contraceptives (Cyclofem® and Mesigyna®) and one oral contraceptive (Ortho-Novum 1/35®) on coagulation and fibrinolysis

A randomized controlled multicenter study was undertaken to monitor the effects on hemostasis of two once-a-month injectable contraceptive preparations, Mesigyna (50 mg norethisterone enanthate and 5 mg estradiol valerate) and Cyclofem (25 mg medroxyprogesterone acetate and 5 mg estradiol cypionate) in comparison with a well-known oral contraceptive (OC) Ortho-Novum 1/35 (norethisterone 1 mg and ethinyl estradiol 35 microg). A total of 378 volunteers from four centers (Bangkok, Hangzhou, Santiago and Singapore) were monitored. Blood sampling took place in one pretreatment cycle, the third and ninth injection intervals and one posttreatment cycle. In each of the three treatment groups, a rise in hemoglobin, and increases in platelet count and in prothrombin time were observed. With treatment there was a significant increase in activated partial thromboplastin time among Mesigyna users, no change among Cyclofem users and a significant decrease among OC users. OC use led to increases in plasma levels of fibrinogen, factor VII, factor X, plasminogen, protein C and decreases in plasma levels of t-PAI and antithrombin. Use of combined injectables induced no change (Cyclofem) or decreases (Mesigyna) in plasma levels of fibrinogen, factor VII, factor X and antithrombin. Use of both combined injectables led to decreases in protein C, slight decreases in plasminogen and increases in plasminogen and fibrinogen. Overall, the injectable preparations may be more beneficial than the oral preparation in not enhancing a hypercoagulable state because of the reduced synthesis of fibrinogen, factors VII and X; however, decreases in antithrombin and protein C, which are potent coagulation inhibitors, may raise some concern. Whether these changes can lead to modifications in the risk of arterial or venous disease can only be ascertained by conducting epidemiological studies.

Prothrombotic coagulation defects and cardiovascular risk factors in young women with acute myocardial infarction

We investigated the effect of prothrombotic coagulation defects in combination with smoking and other conventional risk factors on the risk of myocardial infarction in young women. In 217 women with a first myocardial infarction before the age of 50 years and 763 healthy control women from a population-based case-control study, factor V Leiden and prothrombin 20210A status were determined. Data on major cardiovascular risk factors and oral contraceptive use were combined with the presence or absence of these prothrombotic mutations, and compared between patients and controls. The overall odds ratio for myocardial infarction in the presence of a coagulation defect was 1.1 [95% confidence interval (CI) 0.6-1.9]. The combination of a prothrombotic mutation and current smoking increased the risk of myocardial infarction 12-fold (95% CI 5.7-27) compared with non-smokers without a coagulation defect. Among women who smoked cigarettes, factor V Leiden presence versus absence increased the risk of myocardial infarction by 2.0 (95% CI 0.9-4.6), and prothrombin 20210A presence versus absence had an odds ratio of 1.0 (95% CI 0.3-3.5). We conclude that factor V Leiden and prothrombin 20210A do not add substantially to the overall risk of myocardial infarction in young women. However, in women who smoke, the presence of factor V Leiden increased the risk of myocardial infarction twofold.

Activated protein C resistance determined with a thrombin generation-based test predicts for venous thrombosis in men and women

Activated protein C (APC) resistance, determined with a thrombin-generation-based APC resistance test, may explain risk differences of venous thrombosis in users of second- and third-generation oral contraceptives (OC). To clinically validate this test, we analysed the Leiden thrombophilia case-control study (474 patients with a first episode of deep vein thrombosis and 474 age- and sex-matched control subjects). Data for men and women were analysed separately. As hormonal status in women is known to strongly influence the APC sensitivity ratio (APCsr), additional strata (OC use and menopausal state) were defined. The APCsr was higher in all patients than in control subjects. Odds ratios (OR), using the 90th percentile of all control subjects (APCsr > 4.5) as cut-off, were: 7.5 [95% confidence interval (CI) 1.6-33.8] for men, 3.0 (95% CI 1.0-8.8) for premenopausal women not using OC, 4.8 (95% CI 1.6-14.7) for premenopausal women using OC and 4.7 (95% CI 1.4-15.6) for postmenopausal women. After excluding the carriers of factor V Leiden, the OR became infinite for men (no control had an APCsr > 4.5), 1.4 (95% CI 0.2-8.2) for premenopausal women not using OC, 3.4 (95% CI 1.1-10.8) for premenopausal women using OC and 3.6 (95% CI 0.6-20.5) for postmenopausal women. A high APCsr, determined with the thrombin-generation-based APC resistance test, predicts venous thrombotic risk, in populations with and without factor V Leiden. In addition, acquired APC resistance resulting from OC use predicts an increased risk for venous thrombosis independent of factor V Leiden.

Estrogens, progestogens and thrombosis

Hundreds of millions of women worldwide use either oral contraceptives or postmenopausal hormone replacement. The use of oral contraceptives leads to an increased risk of venous thrombosis, of myocardial infarction, of stroke and of peripheral artery disease, the risks of which are highest during the first year of use. Women with coagulation abnormalities have a higher risk of venous thrombosis when they use oral contraceptives (or postmenopausal hormones) than women without these abnormalities. The risk of venous thrombosis is also higher for preparations containing desogestrel or gestodene (third-generation progestogens) than for those containing levonorgestrel (second-generation progestogens). A previous thrombosis as well as obesity also increase the risk of oral contraceptive-related thrombosis. Hormone replacement therapy increases the risk of venous thrombosis, and has no beneficial, and possibly even a detrimental, effect on the risk of arterial disease. The risk of arterial disease in oral contraceptive users and users of hormone replacement therapy is at most weakly affected by the presence of prothrombotic abnormalities.

Thrombophilias and gynaecology

In gynaecology, women are exposed to sex steroids when using oral contraceptives, hormone replacement therapy or when undergoing in vitro fertilization treatment and ovulation induction. Oral contraceptives and the use of hormone replacement therapy increase the risk of venous thrombosis. The risk is highest in the first year of use and higher among women with clotting defects. Women taking third-generation oral contraceptives have an almost twofold increased risk of venous thrombosis compared with those taking second-generation oral contraceptives. Inherited clotting defects, which are themselves risk factors of venous thrombosis, (e.g. factor V Leiden mutation, deficiency of protein C, protein S or antithrombin, high plasma levels of factor VIII, and prothrombin mutation) appear synergistically increase the risk of venous thrombosis caused by oral contraceptives. Recent studies also point to an interaction between hormone replacement therapy and coagulation defects in causing venous thrombosis. Emerging studies show that in vitro fertilization treatment and ovulation induction are also risk factors for venous thrombosis; the role of coagulation defects in this association is not yet clear.

Validity of the general practice research database

The United Kingdom General Practice Research Database (GPRD) is an office-based, computer-generated, medical resource designed from its inception to be used for epidemiologic research. A distinct version of the GPRD is maintained by the Boston Collaborative Drug Surveillance Program and has been the source of more than 130 scientific articles primarily addressing drug safety issues. We reviewed evidence related to the validity of the GPRD. Specifically, with our extensive experience with this automated database, we evaluated the quality and completeness of the data that it contains.

Oral contraception and the risk of thromboembolism: what does it mean to clinicians and their patients?

For four decades the oral contraceptive pill has remained popular with young women because of its convenience and effectiveness. There have, however, been continuing concerns about adverse effects. In the 1960s the risk of venous thromboembolism was linked to the dose of estrogen, which was consequently reduced. Later the risks of arterial disease were linked to progestogen dose, which was also reduced. In 1995, three case-control studies linked the risk of venous thromboembolism, not to dose, but to the type of progestogen. Newer 'third-generation' progestogens appeared to carry a higher risk than older formulations. Although the contraceptive pill was already known to increase the risk of venous thromboembolism 3- to 6-fold, and the risks in the three studies were within this range, the public perception was that a new risk had been discovered. In the UK there were two consequences--a rapid change in prescribing patterns and a sharp increase in the abortion rate. Critics suggested that the studies may have been affected by confounding--e.g. by a 'new user' effect and differential prescribing. Views became very polarised. Between 1995 and 2001 second- and third-generation formulations were compared in 16 studies. Thirteen found that third-generation pills carried a higher risk of venous thromboembolism. Editorials and reviews recommended second-generation pills as the first choice for new users but official advice was that third-generation pills could still be prescribed, provided the risks were explained. Rates of thrombosis, per 100,000 women, are five for nonusers, 15 with second-generation pills and 25 for third-generation pills. The increase in mortality rates is around 1 to 2 per million. Drug-industry sponsored studies tended to find lower risks than independent studies and it was assumed that sponsorship produces bias, conscious or unconscious. It is also possible that some 'independent' researchers, motivated by antipathy to multinational pharmaceutical companies, are biased in the opposite way. Compared with the energy put into this debate, other aspects of pill prescribing remain under-researched. For example, doctors on opposite sides of the Atlantic are given different advice about whether gross obesity (a major risk factor for thromboembolism) is a contraindication to oral contraception. Women in developing countries continue to die of pregnancy-related causes and many deaths could be prevented by effective contraception. Rather than bickering, drug manufacturers and academics should be discussing ways of providing the pill to the women who need it most.

The effects of seven monophasic oral contraceptive regimens on hemostatic variables: conclusions from a large randomized multicenter study

We investigated the effects of ethinylestradiol dose (50, 30 and 20 microg) and progestogen type [desogestrel (DSG), gestodene (GSD), levonorgestrel (LNG) and norgestimate (NGM)] in oral contraceptives on 24 hemostatic variables. In a multicenter, randomized, comparative study, 707 healthy, nonsmoking, nulliparous women were treated for six cycles with one of the seven monophasic oral contraceptives tested. Significantly greater increases in prothrombin fragment 1+2 and factor VII (activity and antigen), were found in the DSG, NGM and GSD groups compared to the LNG group. Similarly, significantly lower levels of protein S (free and total) and increased APC-sr (endogenous thrombin potential based) were found in the same groups compared with the LNG group. In addition, the estradiol dose (50 vs. 30 microg) significantly influenced these parameters. All changes were within the normal range and have not been associated with an increased risk of venous thromboembolic event (VTE). However, raised levels of these variables are associated with prothrombotic states such as pregnancy. The significance of the haemostatic changes found in this study in relation to VTE risk remains to be determined, but results of this study probably cannot explain the differences in risk of VTE between OCs containing different progestogens.

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.

Urologic manifestations of hematologic disease sickle cell, leukemia, and thromboembolic disease

Advances in medicine are allowing patients with hematologic disease to live longer and healthier lives than ever before. As these patients age, however, manifestations of their disease processes may develop as complications in other organ systems. We discussed the major genitourinary complications of sickle cell anemia, leukemia, and thromboembolic disease. These range from the benign inability to concentrate urine that is seen in sickle cell disease to renal infarction that results from nephrotic syndrome. Our ability to treat and prevent these complications will improve as our understanding of these disease processes and their pathophysiology grows. Additionally, it is important for urologists to understand the underlying pathophysiology of hematologic disease to best serve the patients. For example, it may be the urologist who makes the diagnosis of ovarian vein thrombosis in a pregnant woman with right lower quadrant pain and fever. This diagnosis, with the proper treatment of antibiotics and anticoagulation, could prevent the potential development of septic thrombophlebitis. Urologists will increasingly be called upon to deal with the manifestations of these complex diseases as these patients are living longer. It is our duty to educate ourselves about these disease processes so that we can make the best clinical decisions for our patients.

Venous thromboembolism, oral contraceptives and high prothrombin levels

The G20210A prothrombin mutation, associated with elevated prothrombin levels, is a risk factor for venous thromboembolism (VTE) and displays a strong interaction with oral contraceptives (OC). No data are available on VTE risk of OC use in women with high prothrombin levels, either associated or not with the mutation. The aim of this study was to evaluate the risk of VTE in OC users with high prothrombin levels, either including or excluding carriers of the prothrombin mutation. Prothrombin levels were measured by a chromogenic assay in 152 women who suffered from VTE in reproductive age and in 296 healthy women. Subjects carrying thrombophilic alterations other than the G20210A prothrombin mutation were excluded. Prothrombin levels were stratified into quartiles. The OR of subjects in the upper quartile were 3.10 [95% confidence interval (CI) 1.73-5.55] and 2.07 (95% CI 1.11-3.85) in all women and in those not carrying the prothrombin mutation, respectively. Among the 152 patients, 88 had experienced VTE during OC; in the control group we considered as OC users the women who had used OC for at least 6 months in the 2 years before presentation but had stopped the treatment at least 3 months before the time of blood sampling (n = 127). For the interaction between OC and prothrombin levels only the two extreme strata of prothrombin were considered. Women with the lowest prothrombin levels and who did not use OC were used as reference category. The VTE risk of using OC in subjects with prothrombin levels in the upper quartile was increased 5.4-fold (95% CI 2.38-12.3) and 3.5-fold (95% CI 1.48-8.22) in all women and in those not carrying the prothrombin mutation, respectively. We conclude that elevated prothrombin levels, even in women without the G20210A prothrombin mutation, are associated with an increased risk for venous thromboembolism and that oral contraceptive use potentiates such association.

[Cerebral-vein thrombosis: retrospective study of twenty seven cases]

PURPOSE

Among the locations of venous thrombosis, even if rare, cerebral-vein thrombosis is a severe event with a high mortality rate. No aetiology is found in 20 to 30% of the cases. In recent years, inherited coagulation disorders have been described, as risk factors for venous thrombosis. We report the results of a retrospective study of 27 patients who suffered cerebral-vein thrombosis, in which coagulation abnormalities have been searched for.

METHOD

The patients were referred to the haemostasis laboratory of the Henri Mondor hospital between august 1982 and June 1988, after a cerebral-vein thrombosis. The predisposing factors, personal and family history of thromboembolism, clinical presentation, thrombosis location, evolution under treatment and long-term outcome, have been noted. Deficiencies in antithrombine, protein C, protein S, the Factor V Leiden and the G20210A prothrombin-gene mutation, the presence of lupus anticoagulant, of anticardiolipin antibodies as well as a hyperhomocysteinaemia have been searched, either at the initial presentation, or a posteriori.

RESULTS

Fourty-one percent of patients had a coagulation abnormality. The prevalence of the different abnormalities was: inherited deficiency in AT 7.4%, in PC 8%, in PS 12.5%, factor V Leiden mutation 12%, G20210A prothrombin-gene mutation 12%. Two patients had combined defects: AT and PC deficiency in one, F V Leiden and F II G20210A mutations in one. e of the patient had lupus anticoagulant. Three patients had a significant rate of anticardiolipin antibodies. Five patients out of eight displayed a moderate hyperhomocysteinaemia. Nothing (past history, age, predisposing factors) distinguished those patients bearing a coagulation disorder from the others. The venous thromboembolic relapse rate of 15 % (4/27 patients). Three of them had an inherited thrombophilic abnormality.

CONCLUSION

We recommend an investigation of the haemostasis after every cerebral venous thrombosis.