Andréa A. Garcia

Protein S levels and the risk of venous thrombosis: results from the MEGA case-control study

In thrombophilic families, protein S deficiency is clearly associated with venous thrombosis. We aimed to determine whether the same holds true in a population-based case-control study (n = 5317). Subjects were regarded protein S deficient when protein S levels were < 2.5th percentile of the controls. Free and total protein S deficiency was not associated with venous thrombosis: free protein S < 53 U/dL, odds ratio [OR] 0.82 (95% confidence interval [CI], 0.56-1.21) and total protein S < 68 U/dL, OR 0.90 (95% CI, 0.62-1.31). When lower cutoff values were applied, it appeared that subjects at risk of venous thrombosis could be identified at levels < 0.10th percentile of free protein S (< 33 U/dL, OR 5.4; 95% CI, 0.61-48.8). In contrast, even extremely low total protein S levels were not associated with venous thrombosis. PROS1 was sequenced in 48 subjects with free protein S level < 1st percentile (< 4 6 U/dL), and copy number variations were investigated in 2718 subjects, including all subjects with protein S (free or total) < 2.5th percentile. Mutations in PROS1 were detected in 5 patients and 5 controls reinforcing the observation that inherited protein S deficiency is rare in the general population. Protein S testing and PROS1 testing should not be considered in unselected patients with venous thrombosis.

Effects of the etonogestrel-releasing contraceptive implant inserted immediately postpartum on maternal hemostasis: a randomized controlled trial.

INTRODUCTION The puerperium is the period of highest risk for thrombosis during a womans reproductive life and it is an important time for initiating an effective contraceptive method in order to increase intergestational interval. Thus, the objective of the present study was to evaluated the effects of the etonogestrel (ENG)-releasing contraceptive implant inserted immediately postpartum on maternal hemostasis markers during the first six weeks of delivery. MATERIALS AND METHODS Forty healthy women aged 18 to 35 years-old were randomized to receive either the ENG-releasing implant 24-48 h after delivery (implant group; n=20) or nothing (control group) until the sixth postpartum week. Blood samples were collected at 24-48 h and at 6 weeks after delivery, and hemostatic variables, including fibrinogen, coagulation factors, protein C, free protein S, antithrombin, α2-antiplasmin, plasminogen activator inhibitor 1, thrombin-antithrombin complex (TAT), prothrombin fragment (PF)1+2, and D-dimers, as well as normalized activated protein C sensitivity ratio (nAPCsr), thrombin time, activated partial thromboplastin time, and prothrombin time were evaluated. RESULTS Insertion of the ENG-releasing contraceptive implant did not change the physiological reduction in overall coagulation (TAT and PF1+2) and fibrinolysis (D-dimer) markers, or nAPCsr. Reductions in factors II, VII, X and fibrinogen and increases in factor V were greater in the control than in the implant group. Clotting factors remained within normal limits throughout the study. CONCLUSION The ENG-releasing contraceptive implant inserted immediately postpartum did not have negative effects on physiological variations of the hemostatic system during the first 6 weeks postpartum.

Transitory reduction of platelet aggregation with the use of etonogestrel implant in healthy women

Transitory reduction of platelet aggregation with the use of etonogestrel implant in healthy women -

Oral anticoagulant therapy does not modify the bleeding pattern associated with the levonorgestrel-releasing intrauterine system in women with thrombophilia and/or a history of thrombosis

BACKGROUND Progestogen-only contraceptives (POCs) are suitable for women with thrombophilia and/or a history of venous thromboembolism (VTE). Several of these women, however, use oral anticoagulant therapy (OAT), which can impair the bleeding pattern associated with POC use. We evaluated the effects of OAT use on the bleeding pattern associated with the levonorgestrel-releasing intrauterine system (LNG-IUS) in women with thrombophilia and/or a history of VTE. STUDY DESIGN This prospective cohort study followed two groups of women, all of whom were thrombophilic and/or had a history of VTE: OAT users and nonusers. Bleeding patterns, blood pressure, body mass index (BMI), weight, complete blood count and waist circumference were compared between the two groups before and 6 and 12 months after LNG-IUS insertion. RESULTS The patient cohort consisted of 33 women aged 18 to 45 years old, including 16 OAT users and 17 nonusers. Body weight increased by 3.9% and BMI by 3.8% in OAT users 12 months after LNG-IUS insertion. Hemoglobin and hematocrit levels increased by approximately 10% in both groups. There was no difference between the groups in bleeding patterns, with amenorrhea being the most frequent pattern in both groups (41.2% each) 12 months after LNG-IUS insertion. OAT did not increase the frequency of prolonged and/or frequent bleeding. CONCLUSION OAT users and nonusers had similar bleeding patterns after insertion of the LNG-IUS. Hemoglobin and hematocrit levels increased in both groups.

Error in body weight estimation leads to inadequate parenteral anticoagulation

Parenteral anticoagulation is a cornerstone in the management of venous and arterial thrombosis. Unfractionated heparin has a wide dose/response relationship, requiring frequent and troublesome laboratorial follow-up. Because of all these factors, low-molecular-weight heparin use has been increasing. Inadequate dosage has been pointed out as a potential problem because the use of subjectively estimated weight instead of real measured weight is common practice in the emergency department (ED). To evaluate the impact of inadequate weight estimation on enoxaparin dosage, we investigated the adequacy of anticoagulation of patients in a tertiary ED where subjective weight estimation is common practice. We obtained the estimated, informed, and measured weight of 28 patients in need of parenteral anticoagulation. Basal and steady-state (after the second subcutaneous shot of enoxaparin) anti-Xa activity was obtained as a measure of adequate anticoagulation. The patients were divided into 2 groups according the anticoagulation adequacy. From the 28 patients enrolled, 75% (group 1, n = 21) received at least 0.9 mg/kg per dose BID and 25% (group 2, n = 7) received less than 0.9 mg/kg per dose BID of enoxaparin. Only 4 (14.3%) of all patients had anti-Xa activity less than the inferior limit of the therapeutic range (<0.5 UI/mL), all of them from group 2. In conclusion, when weight estimation was used to determine the enoxaparin dosage, 25% of the patients were inadequately anticoagulated (anti-Xa activity <0.5 UI/mL) during the initial crucial phase of treatment.

Comparison of the hemostatic effects of a levonorgestrel-releasing intrauterine system and leuprolide acetate in women with endometriosis: a randomized clinical trial.

INTRODUCTION The hemostatic and inflammatory systems may activate each other. Endometriosis is a chronic inflammatory disease affecting 10% of women. The objective of this study was to compare the hemostatic effects of two treatments widely prescribed to women with endometriosis: the levonorgestrel intrauterine system (LNG-IUS) and the gonadotropin-releasing hormone analog (GnRHa) leuprolide acetate. MATERIALS AND METHODS In this randomized open-label controlled trial, 44 women with endometriosis were randomly allocated to one of two groups: 22 women were assigned to use LNG-IUS and 22 to use GnRHa. The assessed variables were D-dimers, fibrinogen, prothrombin time, activated partial thromboplastin time, coagulation factors (F) II, V, VII, VIII, IX, X, and XI, antithrombin (AT), protein C, free protein S, tissue plasminogen activator (t-PA), α2-antiplasmin, thrombin-antithrombin complex, and prothrombin fragment 1+2. All variables were assessed before treatment and six months after treatment onset. RESULTS In the LNG-IUS group, FVIII decreased 10% after six months of use. In the GnRHa group, there was a 6% increase in AT, 29% reduction in D-dimers, and 19% increase in t-PA. The LNG-IUS users exhibited a significantly greater reduction of FVIII than the GnRHa users (LNG-IUS: -6.4 ± 14.3% vs. GnRHa: 4.2 ± 12.3%, p=0.02). The women in the GnRHa group exhibited a greater increase of AT than the LNG-IUS users (LNG-IUS: -0.7 ± 9.5% vs. GnRHa: 6.5 ± 10.1%, p=0.02). CONCLUSION Both hormonal treatments for endometriosis exhibited no association with a procoagulant profile.