Karly Hamulyak

Aspirin plus Heparin or Aspirin Alone in Women with Recurrent Miscarriage

BACKGROUND Aspirin and low-molecular-weight heparin are prescribed for women with unexplained recurrent miscarriage, with the goal of improving the rate of live births, but limited data from randomized, controlled trials are available to support the use of these drugs. METHODS In this randomized trial, we enrolled 364 women between the ages of 18 and 42 years who had a history of unexplained recurrent miscarriage and were attempting to conceive or were less than 6 weeks pregnant. We then randomly assigned them to receive daily 80 mg of aspirin plus open-label subcutaneous nadroparin (at a dose of 2850 IU, starting as soon as a viable pregnancy was demonstrated), 80 mg of aspirin alone, or placebo. The primary outcome measure was the live-birth rate. Secondary outcomes included rates of miscarriage, obstetrical complications, and maternal and fetal adverse events. RESULTS Live-birth rates did not differ significantly among the three study groups. The proportions of women who gave birth to a live infant were 54.5% in the group receiving aspirin plus nadroparin (combination-therapy group), 50.8% in the aspirin-only group, and 57.0% in the placebo group (absolute difference in live-birth rate: combination therapy vs. placebo, -2.6 percentage points; 95% confidence interval [CI], -15.0 to 9.9; aspirin only vs. placebo, -6.2 percentage points; 95% CI, -18.8 to 6.4). Among 299 women who became pregnant, the live-birth rates were 69.1% in the combination-therapy group, 61.6% in the aspirin-only group, and 67.0% in the placebo group (absolute difference in live-birth rate: combination therapy vs. placebo, 2.1 percentage points; 95% CI, -10.8 to 15.0; aspirin alone vs. placebo -5.4 percentage points; 95% CI, -18.6 to 7.8). An increased tendency to bruise and swelling or itching at the injection site occurred significantly more frequently in the combination-therapy group than in the other two study groups. CONCLUSIONS Neither aspirin combined with nadroparin nor aspirin alone improved the live-birth rate, as compared with placebo, among women with unexplained recurrent miscarriage. (Current Controlled Trials number, ISRCTN58496168.)

Vitamin K1 Supplementation Retards Bone Loss in Postmenopausal Women Between 50 and 60 Years of Age

Although several observational studies have demonstrated an association between vitamin K status and bone mineral density (BMD) in postmenopausal women, no placebo-controlled intervention trials of the effect of vitamin K1 supplementation on bone loss have been reported thus far. In the trial presented here we have investigated the potential complementary effect of vitamin K1 (1 mg/day) and a mineral + vitamin D supplement (8 µg/day) on postmenopausal bone loss. The design of our study was a randomized, double-blind, placebo-controlled intervention study; 181 healthy postmenopausal women between 50 and 60 years old were recruited, 155 of whom completed the study. During the 3-year treatment period, participants received a daily supplement containing either placebo, or calcium, magnesium, zinc, and vitamin D (MD group), or the same formulation with additional vitamin K1 (MDK group). The main outcome was the change in BMD of the femoral neck and lumbar spine after 3 years, as measured by DXA. The group receiving the supplement containing additional vitamin K1 showed reduced bone loss of the femoral neck: after 3 years the difference between the MDK and the placebo group was 1.7% (95% Cl: 0.35–3.44) and that between the MDK and MD group was 1.3% (95% Cl: 0.10–3.41). No significant differences were observed among the three groups with respect to change of BMD at the site of the lumbar spine. If co-administered with minerals and vitamin D, vitamin K1 may substantially contribute to reducing postmenopausal bone loss at the site of the femoral neck.

Selective testing for thrombophilia in patients with first venous thrombosis: results from a retrospective family cohort study on absolute thrombotic risk for currently known thrombophilic defects in 2479 relatives

Thrombophilia screening is controversial. In a retrospective family cohort, where probands had thrombosis and a thrombophilic defect, 2479 relatives were tested for thrombophilia. In antithrombin-, protein C-, and protein S-deficient relatives, annual incidences of venous thrombosis were 1.77% (95% CI, 1.14-2.60), 1.52% (95% CI, 1.06-2.11), and 1.90% (95% CI, 1.32-2.64), respectively, at a median age of 29 years and a positive family history of more than 20% symptomatic relatives. In relatives with factor V (FV) Leiden, prothrombin 20210G>A, or high FVIII levels, these were 0.49% (95% CI, 0.39-0.60), 0.34% (95% CI, 0.22-0.49), and 0.49% (95% CI, 0.41-0.51), respectively. High FIX, FXI, and TAFI, and hyperhomocysteinemia were not independent risk factors. Annual incidence of major bleeding in antithrombin-, protein C-, or protein S-deficient relatives on anticoagulants was 0.29% (95% CI, 0.03-1.04). Cumulative recurrence rates in relatives with antithrombin, protein C, or protein S deficiency were 19% at 2 years, 40% at 5 years, and 55% at 10 years. In relatives with FV Leiden, prothrombin 20210G>A, or high levels FVIII, these were 7%, 11%, and 25%, respectively. Considering its clinical implications, thrombophilia testing should address hereditary deficiencies of antithrombin, protein C, and protein S in patients with first venous thrombosis at young age and/or a strong family history of venous thrombosis.

Coagulation factors and the protein C system as determinants of thrombin generation in a normal population

Summary.  Background: Thrombin generation is a powerful tool to probe overall plasma coagulability.

Increased risk for Fetal loss in Carriers of the factor V Leiden mutation

BACKGROUND: An increased risk for fetal loss caused by placental thrombosis is probable in carriers of the factor V Leiden mutation but has not been demonstrated consistently in previous studies. OBJECTIVE: To determine the overall risk for fetal loss and the separate risks for miscarriage and stillbirth in carriers of the factor V Leiden mutation. DESIGN: Retrospective cohort study. SETTING: Three university hospitals. PARTICIPANTS: 228 carriers of the factor V Leiden mutation (77 propositi, 151 relatives) and 121 noncarrier relatives (controls). All participants had been pregnant at least once. MEASUREMENTS: Risks for fetal loss, miscarriage (defined as fetal loss within 20 weeks of gestation), and stillbirth (defined as fetal loss after >20 weeks of gestation) in women and in pregnancies were estimated and compared in carriers and noncarriers. Adjusted odds ratios were calculated by using multiple regression analysis. A random-effects model was used for comparisons of pregnancies. RESULTS: Fetal loss occurred in 31.6% of carriers and 22.3% of noncarriers, miscarriage occurred in 29.4% of carriers and 17.4% of noncarriers, and stillbirth occurred in 5.7% of carriers and 5.0% of noncarriers. Fetal loss recurred in 10.1% of carriers and 4.1% of noncarriers (odds ratio, 2.60 [95% CI, 0.96 to 7.03]). Adjusted odds ratios were 2.12 (CI, 1.35 to 3.33) for fetal loss, 2.08 (CI, 1.33 to 3.25) for miscarriage, and 1.60 (CI, 0.58 to 4.43) for still-birth when pregnancies in carriers and noncarriers were compared. Homozygous carriers had a greater risk for fetal loss (odds ratio, 2.01 [CI, 0.94 to 4.32]) and stillbirth (odds ratio, 4.85 [CI, 0.82 to 25.58]) than heterozygous carriers. CONCLUSIONS: Carriers of the factor V Leiden mutation have a greater risk for fetal loss (particularly miscarriage) than noncarriers. These data further suggest a greater risk for recurrence of fetal loss in carriers than in noncarriers and a greater risk for fetal loss and stillbirth in homozygous carriers than in heterozygous carriers

Beneficial effects of vitamins D and K on the elastic properties of the vessel wall in postmenopausal women: a follow-up study

Matrix-Gla Protein (MGP) is a strong inhibitor of vascular calcification, the expression of which is vitamin D dependent. MGP contains five gamma-carboxyglutamic acid (Gla)-residues which are formed in a vitamin K-dependent carboxylation step and which are essential for its function. Hence vascular vitamin K-deficiency will result in undercarboxylated, inactive MGP which is a potential risk factor for calcification. In the present study we describe the effects of vitamin K1 and D supplementation on vascular properties in postmenopausal women. In a randomized placebo-controlled intervention study, 181 postmenopausal women were given either a placebo or a supplement containing minerals and vitamin D (MD-group), or the same supplement with vitamin K1 (MDK-group). 150 participants completed the study and analysis was performed on 108 participants. At baseline and after three years, vessel wall characteristics, including compliance coefficient (CC), distensibility coefficient (DC), intima-media thickness (IMT) and the Youngs Modulus (E) were measured to assess the effect of the supplements on the change of these parameters. The results showed that the elastic properties of the common carotid artery in the MDK-group remained unchanged over the three-year period, but decreased in the MD- and placebo-group. Comparing the MDK- and placebo-group, there were significant differences in decrease of DC (8.8%; p<0.05), CC (8.6%; p<0.05), and in increase of PP (6.3%; p<0.05) and E (13.2%, p<0.01). There were no significant differences between the MD-group and placebo. No significant differences were observed in the change of IMT between the three groups. It is concluded that a supplement containing vitamins K1 and D has a beneficial effect on the elastic properties of the arterial vessel wall.

Early Atherosclerosis Exhibits an Enhanced Procoagulant State

BACKGROUND Thrombin generation in vivo may be important in regulating atherosclerotic progression. In the present study, we examined for the first time the activity and presence of relevant coagulation proteins in relation to the progression of atherosclerosis. METHODS AND RESULTS Both early and stable advanced atherosclerotic lesions were collected pairwise from each individual (n=27) during autopsy. Tissue homogenates were prepared from both total plaques and isolated plaque layers, in which the activity of factors (F) II, X, and XII and tissue factor was determined. Microarray analysis was implemented to elucidate local messenger RNA synthesis of coagulation proteins. Part of each specimen was paraffin embedded, and histological sections were immunohistochemically stained for multiple coagulation markers with the use of commercial antibodies. Data are expressed as median (interquartile range [IQR]). Tissue factor, FII, FX, and FXII activities were significantly higher in early atherosclerotic lesions than in stable advanced atherosclerotic lesions. Endogenous thrombin potential and thrombin-antithrombin complex values consolidated a procoagulant profile of early atherosclerotic lesions (endogenous thrombin potential, 1240 nmol/L x min [IQR, 1173 to 1311]; thrombin-antithrombin complex, 1045 ng/mg [IQR, 842.6 to 1376]) versus stable advanced atherosclerotic lesions (endogenous thrombin potential, 782 nmol/L x min [IQR, 0 to 1151]; thrombin-antithrombin complex, 718.4 ng/mg [IQR, 508.6 to 1151]). Tissue factor, FVII, and FX colocalized with macrophages and smooth muscle cells. In addition, multiple procoagulant and anticoagulant proteases were immunohistochemically mapped to various locations throughout the atherosclerotic vessel wall in both early and advanced atherosclerotic stages. CONCLUSIONS This study shows an enhanced procoagulant state of early-stage atherosclerotic plaques compared with advanced-stage plaques, which may provide novel insights into the role of coagulation during atherosclerotic plaque progression.

Factor VIII gene (F8) mutation and risk of inhibitor development in nonsevere hemophilia A

Neutralizing antibodies (inhibitors) toward factor VIII form a severe complication in nonsevere hemophilia A, profoundly aggravating the bleeding pattern. Identification of high-risk patients is hampered by lack of data that take exposure days to therapeutic factor VIII concentrates into account. In the INSIGHT study, we analyzed the association between F8 mutation and inhibitor development in patients with nonsevere hemophilia A (factor VIII 2-40 IU/dL). This analysis included 1112 nonsevere hemophilia A patients from 14 centers in Europe and Australia that had genotyped at least 70% of their patients. Inhibitor risk was calculated as Kaplan-Meier incidence with cumulative number of exposure days as the time variable. During 44 800 exposure days (median, 24 exposure days per patient; interquartile range [IQR], 7-90), 59 of the 1112 patients developed an inhibitor; cumulative incidence of 5.3% (95% confidence interval [CI], 4.0-6.6) after a median of 28 exposure days (IQR, 12-71). The inhibitor risk at 50 exposure days was 6.7% (95% CI, 4.5-8.9) and at 100 exposure days the risk further increased to 13.3% (95% CI, 9.6-17.0). Among a total of 214 different F8 missense mutations 19 were associated with inhibitor development. These results emphasize the importance of F8 genotyping in nonsevere hemophilia A.

Vitamin K-induced changes in markers for osteoblast activity and urinary calcium loss.

SummaryThe objective of this study was to identify subjects in whom vitamin K has an effect on markers for calcium and bone metabolism and to detect hitherto-unnoticed correlations between vitamin K-induced changes in these markers. Participants in our studies were apparently healthy women, in whom we measured serum-immunoreactive osteocalcin (irOC) before and after adsorption to hydroxylapatite; total serum alkaline phosphatase (T-AP) and bonespecific alkaline phosphatase (B-AP); and fasting urinary calcium and creatinine. We describe a trial among 145 women who were treated with vitamin K (1 mg/day) for 2 weeks, and a prospective placebo-controlled trial among two groups each of 70 postmenopausal women with a treatment period of 3 months. It turned out that in elderly women vitamin K induced increased levels of serum irOC with a high affinity for hydroxylapatite (irOCbound), whereas that with low affinity (irOCfree) remained unaffected. In placebo-treated women the ratio irOCfree/irOCbound shifted from 0.38 to 0.65 around the 50th year of age. This shift was not found in vitamin K-treated women. After 3 months of treatment the vitamin K-induced changes in irOCbound were correlated with changes in B-AP, whereas irOCfree was correlated to urinary calcium excretion. In fast losers of urinary calcium vitamin K induced a 30% decrease of calcium excretion. The hypothesis is put forward that irOCbound may be a marker for bone formation, that serum irOCfree may be a marker for bone resorption, and that the serum irOCfree/irOCbound ratio may become a marker for skeletal remodeling. It is concluded that vitamin K administration may help to reduce urinary calcium loss in postmenopausal women, notably in the fast losers of calcium. The ratio irOCfree/irOCbound provides more information than total irOC and may become a practical marker for bone metabolism.

Assay for Human Matrix Gla Protein in Serum: Potential Applications in the Cardiovascular Field

Matrix Gla protein (MGP) is synthesized in a vitamin K-dependent way in smooth muscle cells of the healthy vessel wall, and its mRNA transcription is substantially upregulated in atherosclerotic lesions. Here we report the preparation of a monoclonal antibody against human MGP and its use in an enzyme-linked immunosorbent assay. The intra-assay and interassay coefficients of variation in serum samples were 5.4% and 12.6%, respectively, and the lower detection limit was 8.5% of the normal serum value. Individual within-day variations were <11% and did not show a distinct circadian pattern. Day-to-day variations in fasting morning samples were <8%. In a first explorative survey, serum MGP concentrations were found to be significantly increased in patients with severe atherosclerosis, whereas these values were normal in those with low bone mass and osteoporosis. This finding is consistent with the high MGP mRNA expression observed in atherosclerotic vessels and plaques. More elaborate studies are required to assess the potential clinical utility of this newly developed assay.