RESUMO
BACKGROUND AND AIMS: While overall gastrointestinal bleeding (GIB) rates have been extensively compared between warfarin and direct oral anticoagulants (DOACs), it is still unclear whether upper and lower GIB rates differ between these types of drugs. This study aimed to compare upper and lower GIB rates between warfarin and DOACs in a nationwide cohort. METHODS: Data on all patients in Iceland who received a prescription for oral anticoagulation from 2014 to 2019 were collected and their personal identification numbers linked to the electronic medical record system of the National University Hospital of Iceland and the 4 regional hospitals in Iceland. Inverse probability weighting was used to yield balanced study groups and rates of overall, major, upper, and lower GIB were compared using Cox regression. All GIB events were manually confirmed by chart review. RESULTS: Warfarin was associated with higher rates of upper GIB (1.7 events per 100 person-years vs 0.8 events per 100 person-years; hazard ratio [HR], 2.12; 95% confidence interval [CI], 1.26-3.59) but similar rates of lower GIB compared with DOACs. Specifically, warfarin was associated with higher rates of upper GIB compared with apixaban (HR, 2.63; 95% CI, 1.35-5.13), dabigatran (5.47; 95% CI, 1.87-16.05), and rivaroxaban (HR, 1.74; 95% CI, 1.00-3.05). Warfarin was associated with higher rates of major GIB compared with apixaban (2.3 events per 100 person-years vs 1.5 events per 100 person-years; HR, 1.79; 95% CI, 1.06-3.05), but otherwise overall and major GIB rates were similar in warfarin and DOAC users. CONCLUSIONS: Warfarin was associated with higher rates of upper but not overall or lower GIB compared with DOACs. Warfarin was associated with higher rates of major GIB compared with apixaban.
Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Varfarina/efeitos adversos , Anticoagulantes/efeitos adversos , Estudos de Coortes , Fibrilação Atrial/complicações , Hemorragia Gastrointestinal/induzido quimicamente , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/complicações , Dabigatrana/efeitos adversos , Administração Oral , Estudos RetrospectivosRESUMO
During warfarin management, variability in prothrombin time-based international normalized ratio (PT-INR) is caused, in part, by clinically inconsequential fluctuations in factor VII (FVII). The new factor II and X (Fiix)-prothrombin time (Fiix-PT) and Fiix-normalized ratio (Fiix-NR), unlike PT-INR, are only affected by reduced FII and FX. We assessed the incidence of thromboembolism (TE) and major bleeding (MB) in all 2667 patients on maintenance-phase warfarin managed at our anticoagulation management service during 30 months; 12 months prior to and 18 months after replacing PT-INR monitoring with Fiix-NR monitoring. Months 13 to 18 were predefined as transitional months. Using 2-segmented regression, a breakpoint in the monthly incidence of TE became evident 6 months after test replacement, that was followed by a 56% reduction in incidence (from 2.82% to 1.23% per patient-year; P = .019). Three-segmented regression did not find any significant trend in TE incidence (slope, +0.03) prior to test replacement; however, during months 13 to 18 and 19 to 30, the incidence of TE decreased gradually (slope, -0.12; R2 = 0.20; P = .007). The incidence of MB (2.79% per patient-year) did not differ. Incidence comparison during the 12-month Fiix and PT periods confirmed a statistically significant reduction (55-62%) in TE. Fiix monitoring reduced testing, dose adjustments, and normalized ratio variability and prolonged testing intervals and time in range. We conclude that ignoring FVII during Fiix-NR monitoring in real-world practice stabilizes the anticoagulant effect of warfarin and associates with a major reduction in TEs without increasing bleeding.
Assuntos
Anticoagulantes/uso terapêutico , Monitoramento de Medicamentos/métodos , Fator VII/análise , Fator X/análise , Hemorragia/induzido quimicamente , Protrombina/análise , Tromboembolia/prevenção & controle , Trombofilia/tratamento farmacológico , Varfarina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Anticoagulantes/farmacologia , Fibrilação Atrial/complicações , Comorbidade , Feminino , Seguimentos , Humanos , Islândia/epidemiologia , Coeficiente Internacional Normatizado , Análise de Séries Temporais Interrompida , Quimioterapia de Manutenção , Masculino , Tempo de Protrombina , Risco , Tromboembolia/epidemiologia , Trombofilia/sangue , Trombofilia/epidemiologia , Varfarina/efeitos adversos , Varfarina/farmacologiaRESUMO
BACKGROUND: Although epistaxis is one of the most common side effects of oral anticoagulation, it is unclear whether epistaxis rates vary between different oral anticoagulants (OAC). OBJECTIVE: To compare rates of clinically relevant epistaxis between OAC. METHODS: Epistaxis event rates were compared between new users of apixaban, dabigatran, rivaroxaban, and warfarin in a nationwide population-based cohort study over a 5-year study period, 2014-2019. Data was collected from the Icelandic Medicine Registry and the five major hospitals in Iceland. Inverse probability weighting (IPW) was used to yield balanced baseline characteristics, and epistaxis rates were compared using Kaplan-Meier survival estimates and Cox regression. RESULTS: During the study period, 2098 patients received apixaban, 474 dabigatran, 3106 rivaroxaban, and 1403 warfarin. In total, 93 patients presented with clinically relevant epistaxis, including 11 (12%) major epistaxis events and one fatal epistaxis episode. Furthermore, seven patients (9%) with non-major epistaxis later presented with major bleeding during the follow-up period. Warfarin use was associated with higher rates of epistaxis compared to apixaban (2.2 events per 100-person years (events/100-py) vs. 0.6 events/100-py, hazard ratio [HR] 4.22, 95% confidence interval [CI] 2.08-8.59, p < 0.001), rivaroxaban (2.2 events/100-py vs. 1.0 events/100-py, HR 2.26, 95% CI 1.28-4.01, p = 0.005), and dabigatran (2.2 events/100-py vs. no events, HR n/a, p < 0.001). CONCLUSION: Warfarin treatment was associated with higher rates of clinically relevant epistaxis compared to direct oral anticoagulants.
Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Administração Oral , Anticoagulantes/uso terapêutico , Fibrilação Atrial/complicações , Estudos de Coortes , Dabigatrana , Epistaxe/induzido quimicamente , Epistaxe/complicações , Epistaxe/epidemiologia , Humanos , Pontuação de Propensão , Piridonas , Estudos Retrospectivos , Rivaroxabana , Acidente Vascular Cerebral/tratamento farmacológico , VarfarinaRESUMO
BACKGROUND: Gastrointestinal bleeding (GIB) rates for direct oral anticoagulants (DOACs) and warfarin have been extensively compared. However, population-based studies comparing GIB rates among different DOACs are limited. OBJECTIVE: To compare rates of GIB among apixaban, dabigatran, and rivaroxaban. DESIGN: Nationwide population-based cohort study. SETTING: Landspítali-The National University Hospital of Iceland and the 4 regional hospitals in Iceland. PATIENTS: New users of apixaban, dabigatran, and rivaroxaban from 2014 to 2019. MEASUREMENTS: Rates of GIB were compared using inverse probability weighting, Kaplan-Meier survival estimates, and Cox regression. RESULTS: In total, 2157 patients receiving apixaban, 494 patients receiving dabigatran, and 3217 patients receiving rivaroxaban were compared. For all patients, rivaroxaban had higher overall rates of GIB (3.2 vs. 2.5 events per 100 person-years; hazard ratio [HR], 1.42 [95% CI, 1.04 to 1.93]) and major GIB (1.9 vs. 1.4 events per 100 person-years; HR, 1.50 [CI, 1.00 to 2.24]) compared with apixaban. Rivaroxaban also had higher GIB rates than dabigatran, with similar point estimates, although the CIs were wider and included the possibility of a null effect. When only patients with atrial fibrillation were included, rivaroxaban was associated with higher rates of overall GIB than apixaban (HR, 1.40 [CI, 1.01 to 1.94]) or dabigatran (HR, 2.04 [CI, 1.17 to 3.55]). Dabigatran was associated with lower rates of upper GIB than rivaroxaban in both analyses. LIMITATIONS: Unmeasured confounding and small subgroup analyses. CONCLUSION: Rivaroxaban was associated with higher GIB rates than apixaban and dabigatran regardless of treatment indication. PRIMARY FUNDING SOURCE: Icelandic Centre for Research and Landspítali-The National University Hospital of Iceland.
Assuntos
Inibidores do Fator Xa/efeitos adversos , Hemorragia Gastrointestinal/induzido quimicamente , Rivaroxabana/efeitos adversos , Idoso , Estudos de Coortes , Dabigatrana/efeitos adversos , Doenças do Sistema Digestório/complicações , Doenças do Sistema Digestório/epidemiologia , Feminino , Seguimentos , Hemorragia Gastrointestinal/epidemiologia , Humanos , Islândia/epidemiologia , Masculino , Pontuação de Propensão , Pirazóis/efeitos adversos , Piridonas/efeitos adversos , Úlcera/complicações , Úlcera/epidemiologiaRESUMO
The antithrombotic effect of vitamin K antagonists (VKA) depends on controlled lowering of the activity of factors (F) II and X whereas reductions in FVII and FIX play little role. PT-INR based monitoring, however, is highly influenced by FVII, which has the shortest half-life of vitamin K-dependent coagulation factors. Hence, variability in the anticoagulant effect of VKA may be partly secondary to an inherent flaw of the traditional monitoring test itself. The Fiix prothrombin time (Fiix-PT) is a novel test that is only sensitive to reductions in FII and FX and is intended to stabilize the VKA effect. Two clinical studies have now demonstrated that when warfarin is monitored with the Fiix-PT based normalized ratio (Fiix-NR) instead of PT-INR, anticoagulation is stabilized and less testing and fewer dose adjustments are needed. Furthermore, the relative risk of thromboembolism was reduced by 50-56% in these studies without an increase in major bleeding.
RESUMO
The new Fiix prothrombin time (Fiix-PT) and its derived Fiix-normalized ratio (Fiix-NR) is affected only by reductions in coagulation factors (F) II and X, the two factors responsible for the antithrombotic effect of vitamin K antagonists (VKA). Due to insensitivity to reductions in the short half-life FVII, the Fiix-NR rises later than standard PT-INR during warfarin initiation. To describe a warfarin initiation nomogram adapted for monitoring with Fiix-NR, anticoagulation development was assessed during use of standard PT-INR based initiation nomogram and after adapting the initiation nomogram for Fiix-NR monitoring. Normalized ratios were retrospectively assessed in consecutive warfarin naïve patients during their first 60 days of warfarin intake for one year prior to (PT-INR period) and for one year after replacing the PT-INR with the Fiix-NR (Fiix-NR period). The INR target was NR 2.0-3.0. We evaluated 160 patients monitored with PT-INR and dosed with the PT-nomogram, 57 monitored with Fiix-INR but dosed with PT-nomogram, and 163 Fiix-NR monitored patients dosed using a new Fiix nomogram. Mean PT-INR over 2.0 was reached on day 7 during the PT-period and remained around 2.5 thereafter. When the PT-nomogram continued in use during Fiix-monitoring significantly more patients became overanticoagulated during days 11-29. After the nomogram was modified to respond to rising Fiix-NR with larger initial dose reduction, the mean Fiix-NR reached over 2 on day 8-9 and remained around 2.5 thereafter. When warfarin is monitored with Fiix-NR, an adjusted dosing nomogram should be used during initiation to prevent early overanticoagulation.
Assuntos
Monitoramento de Medicamentos/métodos , Nomogramas , Tempo de Protrombina , Varfarina/administração & dosagem , Humanos , Coeficiente Internacional Normatizado , Estudos RetrospectivosRESUMO
Fiix-prothrombin time (Fiix-PT) differs from traditional PT in being affected by reduced factor (F) II or FX only. In the randomized controlled Fiix-trial, patients on warfarin monitored with Fiix-PT (Fiix-warfarin patients) had fewer thromboembolisms (TE), similar major bleeding (MB) and more stable anticoagulation than patients monitored with PT (PT-warfarin patients). In the current Fiix-trial report we analyzed how reduced anticoagulation variability during Fiix-PT monitoring was reflected in patients with TE or bleeding. Data from 1143 randomized patients was used. We analyzed the groups for anticoagulation intensity (time within target range; TTR), international normalized ratio (INR) variability (variance growth rate B1; VGR) and dose adjustment frequency. We assessed how these parameters associated with clinically relevant vascular events (CRVE), ie TE or MB or clinically relevant non-MB. TTR was highest in Fiix-warfarin patients without CRVE (median 82%;IQR 72-91) and lowest in PT-warfarin patients with TE (62%;56-81). VGR was lowest in Fiix-warfarin patients without CRVE (median VGR B1 0.17; 95% CI 0.08-0.38) and with TE (0.20;0.07-0.26) and highest in PT-warfarin patients with TE (0.50;0.27-0.90) or MB (0.59;0.07-1.36). The mean annual dose adjustment frequency was lowest in Fiix-warfarin patients with TE (mean 5.4;95% CI 3.9-7.3) and without CRVE (mean 6.0; 5.8-6.2) and highest in PT-warfarin patients with TE (14.2;12.2-16.3). Frequent dose changes predicted MB in both study arms. Compared to patients monitored with PT, high anticoagulation stability in Fiix-warfarin patients coincided with their low TE rate. Those with bleeding had high variability irrespective of monitoring method. Thus, although further improvements are needed to reduce bleeding, stabilization of anticoagulation by Fiix-PT monitoring associates with reduced TE.
Assuntos
Anticoagulantes/administração & dosagem , Monitoramento de Medicamentos/métodos , Tempo de Protrombina , Tromboembolia/tratamento farmacológico , Varfarina/administração & dosagem , Fator X/farmacologia , Feminino , Hemorragia/induzido quimicamente , Humanos , Coeficiente Internacional Normatizado , Masculino , Protrombina/farmacologia , Tromboembolia/prevenção & controleRESUMO
Bernard-Soulier syndrome (BSS) is a rare severe autosomal recessive bleeding disorder. To date heterozygous carriers of BSS mutations have not been shown to have bleeding symptoms. We assessed bleeding using a semi-quantitative questionnaire, platelet parameters, PFA-100 closure times, ristocetin response, GP Ib/IX expression and VWF antigen in 14 BSS patients, 30 heterozygote carriers for related mutations and 29 controls. Eight mutations in GP1BA, GP1BB or GP9 were identified including four previously unknown pathogenic mutations. Subjects with BSS reported markedly more mucocutaneous bleeding than controls. Increased bleeding was also observed in heterozygotes. Compared to controls, patients with BSS had lower optical platelet counts (P < 0.001), CD61-platelet counts (P < 0.001) and higher mean platelet volume (17.7 vs. 7.8 fL, P < 0.001) and ristocetin response and closure times were unmeasurable. Heterozygotes had higher MPV (9.7 fL, P < 0.001) and lower platelet counts (P < 0.001) than controls but response to ristocetin and closure times were normal. The VWF was elevated in both BSS and in heterozygotes (P = 0.005). We conclude that heterozygotes for BSS mutations have lower platelet counts than controls and show a bleeding phenotype albeit much milder than in BSS. Both patients with BSS and heterozygote carriers of pathogenic mutations have raised VWF.
Assuntos
Síndrome de Bernard-Soulier/genética , Heterozigoto , Mutação , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Fator de von Willebrand/genética , Adolescente , Adulto , Idoso , Síndrome de Bernard-Soulier/diagnóstico , Síndrome de Bernard-Soulier/fisiopatologia , Coagulação Sanguínea , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Plaquetas/patologia , Criança , Coagulantes/farmacologia , Feminino , Expressão Gênica , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Contagem de Plaquetas , Ristocetina/farmacologia , Índice de Gravidade de Doença , Inquéritos e QuestionáriosRESUMO
Women with Bernard-Soulier syndrome (BSS) are considered to be at high risk of serious bleeding during childbirth. Due to the frequently occurring platelet transfusion refractoriness, alternative prophylactic therapy is required. Using rotational thromboelastometry, we evaluated the whole blood coagulation profile of a pregnant woman with BSS before and after spiking ex vivo with different concentrations of recombinant activated factor VII (rFVIIa) and fibrinogen. As experiments suggested improved clotting with clinically applicable concentrations of both agents in a complementary manner, the findings were confirmed on blood from a non-pregnant woman and three men suffering from BSS. During delivery, bleeding refractory to platelets occurred and immediately following delivery she received both rFVIIa and fibrinogen intravenously. Immediate cessation of bleeding occurred, and no postpartum hemorrhage was seen. Another woman with BSS later also received the same rFVIIa and fibrinogen treatment prophylactically after delivery without any postpartum bleeding. Eventually, the first woman during her second delivery received the same treatment again prophylactically without any bleeding. No side effects were observed during these three deliveries. Our observations suggest that rFVIIa combined with fibrinogen may provide a beneficial clinical hemostatic effect partly by separate but complementary mechanisms.
Assuntos
Síndrome de Bernard-Soulier/sangue , Fibrinogênio/farmacologia , Adulto , Coagulação Sanguínea/efeitos dos fármacos , Feminino , Hemorragia/prevenção & controle , Humanos , Fatores de RiscoRESUMO
OBJECTIVE: Previous observational studies have yielded conflicting results on whether medication adherence differs between patients receiving warfarin and direct oral anticoagulants (DOACs). Importantly, no study has adequately accounted for warfarin dosing being continuously modified based on INR values while dosing of DOACs is fixed. We aimed to compare non-adherence between new users of apixaban, dabigatran, rivaroxaban and warfarin in a population-based cohort. METHODS: New users of apixaban, dabigatran, rivaroxaban and warfarin from 2014 to 2019 living in the Icelandic capital area were included. Non-adherence was defined as proportion of days covered below 80%. Inverse probability weighting was used to yield balanced study groups and non-adherence was compared using logistic regression. Factors associated with non-adherence were estimated using multivariable logistic regression. RESULTS: Overall, 1266 patients received apixaban, 247 dabigatran, 1566 rivaroxaban and 768 warfarin. The proportion of patients with non-adherence ranged from 10.5% to 16.7%. Dabigatran was associated with significantly higher odds of non-adherence compared with apixaban (OR 1.57, 95% CI 1.21 to 2.04, p<0.001), rivaroxaban (OR 1.45, 95% CI 1.12 to 1.89, p=0.005) and warfarin (OR 1.63, 95% CI 1.23 to 2.15, p<0.001). The odds of non-adherence were similar for apixaban, rivaroxaban and warfarin. Apart from the type of oral anticoagulants (OACs) used, female sex, hypertension, history of cerebrovascular accident and concomitant statin use were all independently associated with lower odds of non-adherence. CONCLUSION: Dabigatran was associated with higher odds of non-adherence compared with other OACs. Non-adherence was similar between apixaban, rivaroxaban and warfarin users. Female sex and higher comorbidity were associated with better medication adherence.
Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Feminino , Varfarina/uso terapêutico , Rivaroxabana/uso terapêutico , Dabigatrana/uso terapêutico , Estudos de Coortes , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/complicações , Anticoagulantes/uso terapêutico , Acidente Vascular Cerebral/complicações , Piridonas/uso terapêutico , Adesão à Medicação , Administração Oral , Estudos RetrospectivosRESUMO
In the pivotal randomized controlled trials (RCTs) for patients with atrial fibrillation, direct oral anticoagulants (DOACs) had similar or even superior efficacy and safety compared with warfarin. However, RCTs comparing different DOACs are nonexistent and previous observational studies have yielded conflicting results. In this nationwide cohort study, rates of any stroke or systemic embolism (stroke/SE) and major bleeding were compared among new users of apixaban, dabigatran, and rivaroxaban with atrial fibrillation from 2014 to 2019. Inverse probability weighting was used to yield balanced study groups, and outcomes were compared using Cox regression. Stroke/SE rates were similar in patients receiving apixaban, dabigatran, and rivaroxaban. Dabigatran was associated with twofold higher rates of myocardial infarction (MI) than rivaroxaban (1.4 events/100 person-years (py) vs 0.7 events/100-py, hazard ratio [HR] 2.21, 95% confidence interval [CI], 1.00-4.90) and apixaban (1.4 events/100-py vs 0.7 events/100-py, HR 2.26, 95% CI, 0.90-5.67), although the second comparison included the possibility of a null effect. Rivaroxaban was associated with higher major bleeding rates compared with apixaban (2.9 events/100-py vs 1.8 events/100-py, HR 1.64, 95% CI, 1.13-2.37) and dabigatran (2.9 events/100-py vs 1.4 events/100-py, HR 2.18, 95% CI, 1.21-3.93). Specifically, rivaroxaban had higher rates of major gastrointestinal bleeding and other major bleeding than apixaban. In conclusion, although stroke/SE rates were similar for DOACs, rivaroxaban was associated with higher rates of major bleeding than other DOACs and lower rates of MI than dabigatran. These results may help guide oral anticoagulant selection, especially in patients at high risk of bleeding or MI.
Assuntos
Fibrilação Atrial , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/induzido quimicamente , Dabigatrana/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Pontuação de Propensão , Rivaroxabana/efeitos adversos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controleRESUMO
OBJECTIVE: To investigate the association between menstrual flow weight measured from modern sanitary pads (converting liquid to non-evaporating gel) and clinically assessed normal, increased or decreased menstrual flow. DESIGN: Objective method development study. SETTING: Outpatient clinic, University Hospital, Reykjavik. POPULATION: One hundred and thirteen volunteers included 26 normally menstruating adult women and 52 normally menstruating teenagers not using oral or intrauterine contraception, seven normally menstruating women using oral contraception, 17 women with clinically diagnosed menorrhagia, five women using oral contraception for clinical menorrhagia, and six teenage girls claiming heavy menstrual flow. METHODS: Menstruation length, menstrual flow weight and history of iron deficiency were assessed. During the menstruation following recruitment, all women collected their used protective pads in a hygienic manner and returned them to the laboratory for accurate weighing. MAIN OUTCOME MEASURES: Menstrual flow total weight measured in grams. RESULTS: Mean menstrual flow total weight in the 78 asymptomatic women was 51 g (median 44, range 5-144). The mean flow in 17 women clinically diagnosed with menorrhagia was 217 g (median 207, range 63-402) (p<0.0001 compared to healthy women). The seven healthy women using oral contraceptives discharged 13 g (13-19) (p=0.0004 compared with normals). Menstruation lasted < eight days in 77/78 healthy women and in 12 of 17 clinically diagnosed menorrhagic women. CONCLUSIONS: Measurement of menstrual flow total weight accurately reflects clinically assessed normal, increased and decreased flow. The method is an easy and accurate way of objectively estimating menstrual flow.
Assuntos
Menorragia/diagnóstico , Produtos de Higiene Menstrual , Menstruação , Adolescente , Adulto , Anticoncepcionais Orais , Feminino , Humanos , Menorragia/fisiopatologia , Pessoa de Meia-Idade , Paridade , Gravidez , Adulto JovemRESUMO
BACKGROUND: Rapid fluctuations in factor VII during warfarin anticoagulation change the international normalised ratio (INR) but contribute little to the antithrombotic effect. We aimed to assess non-inferiority of anticoagulation stabilisation with a warfarin monitoring method affected only by factors II and X (Fiix-prothrombin time [Fiix-PT]) compared with standard PT-INR monitoring that includes factor VII measurement as well. METHODS: The Fiix trial was a single centre, double-blind, prospective, non-inferiority, randomised controlled clinical trial. Ambulatory adults on warfarin with an INR target of 2-3 managed by an anticoagulation dosing service using software-assisted dosing at the National University Hospital of Iceland, Reykjavik, Iceland, were eligible for inclusion in this study. We excluded patients undergoing electroconversion and nursing home residents. Patients were randomly assigned (1:1) to either the Fiix-PT monitoring group or the PT monitoring group by block randomisation. A blinded research INR (R-INR) based on results of the respective test was reported to the dosing staff. Participants were contacted by a study nurse at 4-week intervals to elicit information about thromboembolism or bleeding otherwise unknown to the anticoagulation management centre. The primary efficacy outcome was a composite of objectively diagnosed non-fatal and fatal arterial or venous thromboembolism, including myocardial infarction and transient ischaemic attacks, assessed in all eligible patients who were randomised (intention-to-monitor population). The safety endpoint was major bleeding or other clinically relevant bleeding, assessed in the per-protocol population. We assumed a 3% annual thromboembolism incidence and a non-inferiority margin of 2·5%. This trial is registered with ClinicalTrials.gov, number NCT01565239. FINDINGS: Between March 1, 2012, and Feb 28, 2014, we enrolled 1156 patients. 573 patients were assigned to Fiix-PT and 575 to PT-INR monitoring after exclusion of four patients from each group for various reasons. Median follow-up was 1·7 years (IQR 1·1-1·9). During days 1-720, ten (1·2% per patient year) thromboembolic events occurred in the Fiix-PT group versus 19 (2·3% per patient year) in the PT group (relative risk [RR] 0·52, 95% CI 0·25-1·13; pnon-inferiority<0·0001). Major bleeding occurred in 17 of 571 patients in the Fiix group (2·2% per patient year) versus 20 of 573 patients in the PT group (2·5% per patient year; RR 0·85, 0·45-1·61; pnon-inferiority=0·0034). Anticoagulation stability was improved with Fiix-PT monitoring as manifested by fewer tests, fewer dose adjustments, increased time in range and less INR variability than reported with standard PT monitoring. INTERPRETATION: Monitoring of warfarin with Fiix-PT improved anticoagulation and dosing stability and was clinically non-inferior to PT monitoring. Results from this trial suggest that during vitamin K antagonist treatment INR monitoring could be replaced by Fiix-PT and that this would lead to at least a non-inferior clinical outcome compared with monitoring with PT-INR. FUNDING: Innovation Center Iceland, University of Iceland Science Fund, Landspitali Science Fund and Actavis.
Assuntos
Anticoagulantes/uso terapêutico , Tempo de Protrombina/métodos , Varfarina/uso terapêutico , Idoso , Método Duplo-Cego , Feminino , Humanos , Islândia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tromboembolia/prevenção & controleAssuntos
Hemorragia/etiologia , Doenças de von Willebrand/sangue , Fator de von Willebrand/análise , Regulação para Baixo , Hemorragia/sangue , Hemorragia/genética , Humanos , Índice de Gravidade de Doença , Doenças de von Willebrand/complicações , Doenças de von Willebrand/genética , Fator de von Willebrand/genéticaRESUMO
INTRODUCTION: The prevalence and etiology of occult bleeding among patients on warfarin who are screened systematically for new anemia is largely unknown. We aimed to estimate the usefulness of following hemoglobin and mean red cell volume (MCV) with INR in order to screen for developing anemia as an indicator of occult bleeding. MATERIAL AND METHODS: All patients on warfarin controlled at our institution had measurements of complete blood count (CBC) with INR during 18 months. Patients who fell>25 g/L and/or decrease of MCV over 5 fL or MCV<80 fL were contacted with instructions to undergo evaluation of anemia. RESULTS: Overall 3218 patients on warfarin were monitored at our institution and 442 (13.7%) had anemia and 235 (7.3%) had unexplained anemia. A total of 163/235 (69%) who were notified contacted their doctors and 82/163 (50%) were referred for investigation with upper and/or lower endoscopies. Gastrointestinal malignancies were found in 11 patients (10 colorectal cancers, 1 esophageal) and pre-cancerous lesions among 14 other patients. Additional 25/82 patients (30%) had upper and/or lower bleeding lesions such as ulcers and angiodysplasia. Based on 3669 years of observation, 73 patients needed to be screened for one year in order to identify one gastrointestinal lesion causing occult bleeding. CONCLUSIONS: Thirty percent of those endoscoped had malignant or pre-malignant diseases. Regular measurement of CBC concomitantly with INR in patients on warfarin therapy led to detection of otherwise asymptomatic diseases in a significant proportion of patients and might lead to earlier diagnosis of malignant and premalignant disease.
Assuntos
Anemia/epidemiologia , Anemia/prevenção & controle , Neoplasias Gastrointestinais/diagnóstico , Programas de Rastreamento/estatística & dados numéricos , Lesões Pré-Cancerosas/diagnóstico , Varfarina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia/diagnóstico , Anticoagulantes , Contagem de Células Sanguíneas/estatística & dados numéricos , Criança , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Feminino , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/prevenção & controle , Humanos , Islândia/epidemiologia , Incidência , Coeficiente Internacional Normatizado/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/prevenção & controle , Prevalência , Medição de Risco , Adulto JovemRESUMO
Vitamin K antagonists (VKA) are monitored with prothrombin time (PT) based assays that are equally sensitive to reductions in factors II, VII or X. We compared the effect of vitamin K dependent (VKD) coagulation factors on PT and also on rotational thromboelastometric (ROTEM) parameters. The PT was equally sensitive to reductions in factors II, VII or X but ROTEM parameters correlated poorly with the PT in anticoagulated patients´ plasmas. ROTEM parameters were more affected by mild and moderate reductions in FII or FX than by FVII or FIX which had little influence except at very low coagulant activity. We developed a modified PT that was sensitive only to reductions in factors II and X. The Fiix-PT (Fiix-INR) correlated well with PT (INR) but the Fiix-INR fluctuated less than the INR in an anticoagulated patient reflecting its insensitivity to FVII. The ROTEM results suggest that mild to moderate reductions in factors II or X are more important during clot formation than factors VII or IX. Reductions in FII and X may better reflect anticoagulation with VKA than FVII or IX. The new Fiix-PT may more accurately reflect the degree of therapeutic anticoagulation in patients treated with VKA than the current PT which is subject to a confounding variation caused by FVII.
Assuntos
Anticoagulantes/uso terapêutico , Fator X/metabolismo , Tempo de Protrombina/métodos , Protrombina/metabolismo , Varfarina/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Feminino , Humanos , Coeficiente Internacional Normatizado , MasculinoRESUMO
Cardiac surgery involving cardio pulmonary bypass (CPB) may be associated with development of a coagulopathy that increases risk of bleeding. In the present ex vivo study we investigated the influence of fibrinogen and rFVIIa, alone or in combination, on whole blood coagulation thromboelastometry using pre- and postoperative blood samples from 18 consecutive adult patients undergoing CPB surgery. Dynamic thromboelastometric clotting profiles were recorded using citrated whole blood activated with trace amounts of tissue factor (Innovin, final dilution 1:17000). Blood samples were collected before surgery (control) and postoperative samples were obtained following in vivo neutralization of heparin with protamine sulphate. All blood samples were treated with heparinase to ensure neutralization of possible residual heparin effect. The post-operative blood samples were spiked with buffer, rFVIIa (2 microg/mL), fibrinogen (1 mg/mL), or the combination of rFVIIa and fibrinogen. Despite neutralization of heparin, CPB surgery left a measurable coagulopathy that was thromboelastometrically characterized by prolonged onset of clotting, reduced maximum velocity of clot formation (MaxVel), and decreased maximum clot firmness (MCF). Ex vivo spiking of the postoperative samples with rFVIIa shortened the clotting time. Fibrinogen also shortened the clotting time and, in addition, improved the MaxVel, and MCF. Finally, adding the combination of rFVIIa and fibrinogen to the postoperative samples corrected all thromboelastometric parameters to the preoperative range. In conclusion, the correction of whole blood clotting abnormalities that occurs with rFVIIa and/or fibrinogen suggests that future clinical trials on treatment of bleeding during CPB surgery should study the haemostatic effect of fibrinogen or possibly the combination of rFVIIa and fibrinogen.
Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Ponte Cardiopulmonar/métodos , Fator VIIa/administração & dosagem , Fibrinogênio/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes de Coagulação Sanguínea , Plaquetas/metabolismo , Fibrinogênio/metabolismo , Heparina/química , Heparina Liase/química , Humanos , Pessoa de Meia-Idade , Protaminas/química , Proteínas Recombinantes/administração & dosagemRESUMO
Congenital deficiency of coagulation factor VII is a rare autosomal and usually recessive genetic bleeding disorder which has been discovered in an Icelandic family. The propositus is a male who experienced intermittent painful inflammation of his ankle joints at the age of 9-10 and later also in his knees, elbow, shoulder, and wrist. Smaller joints were spared, serologies for rheumatoid disease were negative. He was treated for rheumatoid arthritis with limited results and became practically invalid due to his arthritis at the age of 40. At the age of 57, a surgical synovectomy of his knee joint was complicated by postoperative bleeding, and signs of chronic haemorrhagic arthritis were noted in the synovia. Subsequently, a marked prolongation of his prothrombin time and a near total deficiency of coagulation factor VII were discovered. All of his nine siblings were deficient in coagulation factor VII, three of them markedly deficient like the proband and six moderetely deficient. The pattern of inheritance suggests that one of their parents was heterozygous and the other homozygous or doubly heterozygous of genetic deficiency of coagulation factor VII. The parents were second cousins. Of the siblings, only the propositus had a bleeding tendency or arthritis. No evidence of such symptoms in their parents or grandparents was found. This family is the only Icelandic family with congenital deficiency of coagulation factor VII known to the authors.