Relationship Between ABCB1 Polymorphisms,Thromboelastography and Risk of Bleeding Events in Clopidogrel-Treated Patients With ST-Elevation Myocardial Infarction

Introduction

This study sought to investigate the relationship of polymorphisms in ABCB1 and the predictive value of thromboelastography (TEG) on bleeding risk in clopidogrel-treated patients with ST-elevation myocardial infarction (STEMI).

Methods

467 consecutive patients with STEMI undergoing percutaneous coronary intervention (PCI) were enrolled. Twenty tag single nucleotide polymorphisms (SNPs) selected from ABCB1 gene and CYP2C19*2, *3, *17 were detected by the ligase detection reaction. Platelet reactivity was assessed by TEG. The follow-up period was 12 months.

Results

By receiver operating characteristic curve analysis, the TEG platelet mapping assay value of ADP inhibition had the best predictive value of bleeding academic research consortium definition (BARC) ≥ 3b bleedings, yielding an area under the curve (AUC) of 0.707 (95% CI 0.662-0.749, p = 0.009; cut-off value > 93.4%). ADP inhibition can also predict BARC ≥ 3 bleedings with an AUC of 0.594 (95% CI 0.546-0.640, p = 0.05; cut-off value > 92.5%). After adjustment for established risk factors of bleeding including the gain of function CYP2C19*17 allele, age, female gender, renal function, the multivariable logistic regression model demonstrated that ADP inhibition > 92.5% (OR 2.247, 95%CI 1.082-4.665, P = 0.03), carriage of rs1045642 (OR 2.943, 95%CI 1.195-7.247, P = 0.019) and rs7779562 (OR 0.453, 95%CI 0.219-0.936, P = 0.032) were independent predictors of BARC ≥ 3 bleedings. These associations were validated in a second cohort of 504 STEMI patients.

Conclusions

In STEMI patients treated with clopidogrel after PCI, the ABCB1 tag SNP rs1045642 is associated with higher risk of bleedings while rs7779562 is associated with lower bleeding risk, and ADP inhibition in TEG has a predictive value of bleedings.     

Has the incidence of deep vein thrombosis in patients undergoing total hip/knee arthroplasty changed over time? A systematic review of randomized controlled trials

Background

There is a perception in the orthopaedic and thromboembolism community that the incidence of deep vein thrombosis (DVT) has decreased in patients undergoing total knee arthroplasty (TKA) or total hip arthroplasty (THA).

Objectives

To assess the incidence of DVT with warfarin thromboprophylaxis over time in patients undergoing elective TKA or THA.

Methods

The MEDLINE, EMBASE, and Cochrane Library databases were searched to October 2006, supplemented by a manual search of reference lists. Two reviewers independently extracted data on study characteristics, quality and the frequency of total, symptomatic and proximal DVT.

Results

Fourteen studies (4,423 patients) were included. Total and proximal DVT after TKA declined over time (r = − 0.75, p = 0.031; r = − 0.86, p = 0.007 respectively). Total and proximal DVT after THA did not change. The risk of developing DVT after TKA was significantly higher than after THA (OR 1.85, 95% CI 1.6 - 2.14; p < 0.0001). The risk of developing symptomatic DVT after THA was significantly higher than after TKA (OR 2.18, 95% CI 1.11 - 4.27; p = 0.012).

Conclusions

The incidence of DVT in patients undergoing elective TKA appears to have declined in patients receiving warfarin thromboprophylaxis.     

Biomarkers for post thrombotic syndrome: A case-control study

Introduction

There is limited knowledge on the etiology of post thrombotic syndrome (PTS), although several mechanisms have been proposed.The objectives are to explore the role of different pathogenic mechanisms for PTS, through measurement of an elaborate panel of biomarkers in patients with and without PTS.

Materials and Methods

Patients with a history of deep vein thrombosis (DVT) with PTS (cases) and without PTS after minimal 2 years follow-up (controls), were selected from the outpatient clinic of two Dutch hospitals. As a reference to the normal population healthy individuals (HI) without a history of venous thromboembolism were invited to participate. The population consisted of: 26 cases, 27 controls, and 26 HI.A panel of predefined biomarkers was measured in venous blood.

Results

D-dimer showed a decreasing trend from cases to controls to HI; p = 0.010. Thrombin/antithrombin complex levels were significantly higher in cases than in controls; p = 0.032, and HI; p = 0.017. APC-ratio was significantly lower in cases compared to controls; p = 0.032, and HI; p = 0.011. A significant trend of increasing proTAFI from cases, to controls, and HI; p = 0.002 was found. There were no differences in inflammatory markers (CRP, Interleukin-6, Interleukin-8). Thrombomodulin, tissue-plasminogen activator, and von Willebrand factor were higher in patients compared to HI. There was a significant trend of decreasing sVCAM, from cases, to controls, and HI; p = 0.029.

Conclusions

Patients with PTS displayed increased coagulation activity, an altered pattern of fibrinolytic marker expression, and increased endothelial activation. We found no evidence of systemic inflammation in patients with PTS at 63 months since the last DVT.     

Incidence and predictive factors of symptomatic thrombosis related to peripherally inserted central catheters in chemotherapy patients

Introduction

The incidence of symptomatic catheter-related deep vein thrombosis (DVT) in cancer patients remains unclear and there is a lack of reliable data on the risk factors of PICC-related DVT.

Materials and Methods

We performed a retrospective cohort study of consecutive cancer patients who received an ultrasound guided PICC line for the administration of chemotherapy. Univariable and multivariable logistic regression analyses were performed to identify risk factors for symptomatic PICC-related DVT.

Results

In total, 340 cancer patients obtained PICC lines for the administration of chemotherapy. Of these patients, 19 (5.6%; 95% CI: 3.6-8.6) developed symptomatic PICC-related DVT. Factors previously associated with catheter-related DVT, including side of catheter placement, lumen size, tip location, need for repositioning, and number of insertion attempts, were not significant determinants in our analysis. Patients with diabetes were three times more likely to develop PICC-related DVT (OR 3.0, p = 0.039), while the presence of COPD and metastatic cancer also increased the odds (OR 3.3, p = 0.078 and OR 2.3, p = 0.083 respectively). Diabetes remained a significant risk factor after adjustment for effect of metastases and COPD (OR 3.175, p = 0.039). Further, the presence of metastases was a significant predictor (OR 3.34, p = 0.024) in our multivariable model.

Conclusions

Symptomatic PICC-related DVT are frequent in cancer patients receiving chemotherapy. Previously described factors associated with catheter-related thrombosis were not predictive of PICC-related DVT in our study. Diabetes, advanced disease and COPD appear to increase the risk of developing PICC-related DVT in chemotherapy patients.     

Incidence and characteristics of asymptomatic distal deep vein thrombosis unexpectedly found at admission in an Internal Medicine setting

Introduction

Lower limb deep vein thrombosis (DVT) is the most frequent clinical manifestation of venous thromboembolism (VTE) and can involve proximal or distal veins. Distal DVT (dDVT) is often asymptomatic and data about its incidence and prognosis are scanty, especially in high risk medical inpatients. Therefore, no consensus exists on the value of detecting and treating dDVTs. Aim of study was to evaluate incidence and characteristics of asymptomatic isolated dDVT at admission in an Internal Medicine department.

Materials and methods

Consecutive patients hospitalized for acute medical illnesses, in whom VTE was not the admission diagnosis, underwent Doppler Ultrasonography. For all patients with dDVT standard treatment with therapeutic doses of low molecular weight heparin or fondaparinux was proposed. Follow-up visits were scheduled at 1, 6 and 12 weeks.

Results

One-hundred-fifty-four patients were enrolled. In 4.5% a proximal DVT and in 16.2% an asymptomatic dDVT were found. Female sex, elevated age and renal and electrolyte abnormalities were significantly associated to dDVT (p = 0.014, p = 0.009 and p = 0.046, respectively). Only low degree of mobility (LDM) was independently associated to dDVT [OR 7.97 (95%CI 2.42-26.27), p = 0.001)]. A high mortality rate, not for VTE-related causes, was found, especially in the first week, among dDVT patients.

Conclusions

We found a high incidence of clinically silent dDVTs. LDM evaluation could be useful to select patients at high risk in whom to perform a search for dDVT.     

Who are at risk for thromboembolism after arthroplasty? A systematic review and meta-analysis

Background

Thromboembolism, including deep venous thrombosis and pulmonary embolism, is a grave threat to patients undergoing total joint replacement. Using a systematic review and meta-analysis we asked whether gene mutations or polymorphisms could be risk factors for thrombosis after arthroplasty.

Methods

We performed a comprehensive search of Medline, PubMed, Embase, Cochrane databases, China National Knowledge Infrastructure (CNKI), and Google Scholar, and identified 19 studies detailing genetic investigations of patients with thromboembolism following joint replacement.

Results

Our meta-analyses included 5149 patients who underwent arthroplasty surgery. Significant associations with venous thromboembolism were identified for factor G1691A (odds ratio (OR) 1.41, 95% confidence interval (CI) 1.03 - 1.94, p = 0.03), prothrombin G20210A (OR 2.16, 95% CI, 1.27- 3.69, p = 0.005), and MTHFR/C677T/TT (OR 2.36, 95% CI 1.03 - 5.42, p = 0.04) in Caucasian populations. No significant gene mutation was identified in Asian populations.

Conclusion

This study suggests a way to identify patients scheduled for arthroplasty who are at higher risk of thrombosis, enabling individualized treatment.     

Risk factors and clinical profile of thrombotic thrombocytopenic purpura in systemic lupus erythematosus patients. Is this a distinctive clinical entity in the thrombotic microangiopathy spectrum?: A case control study

Introduction

The association of thrombotic thrombocytopenic purpura (TTP) with systemic lupus erythematosus (SLE) is rare. It is associated with high morbidity and mortality. Information about risk factors and clinical outcomes is scant.

Material and Methods

A retrospective case-control study was performed in a referral center in Mexico City between 1994 and 2013. Patients were diagnosed with TTP if they fulfilled the following criteria: microangiopathic haemolytic anaemia, thrombocytopenia, high LDH levels, normal fibrinogen and negative Coombs’ test. Patients with SLE were diagnosed with ≥ 4 ACR criteria. We included three study groups: group A included patients with SLE-associated TTP (TTP/SLE; cases n = 22, TTP events n = 24); patients with non-autoimmune TTP (NA-TTP; cases n = 19, TTP events n = 22) were included in group B and patients with SLE without TTP (n = 48) in group C.

Results

After multivariate analysis, lymphopenia < 1000/mm3 [OR 19.84, p = 0.037], high SLEDAI score three months prior to hospitalisation [OR 1.54, p = 0.028], Hg < 7 g/dL [OR 6.81, p = 0.026], low levels of indirect bilirubin [OR 0.51, p = 0.007], and less severe thrombocytopenia [OR 0.98, p = 0.009] were associated with TTP in SLE patients. Patients with TTP/SLE received increased cumulative steroid dose vs. NA-TTP (p = 0.006) and a higher number of immunosuppressive drugs (p = 0.015). Patients with TTP/SLE had higher survival than NA-TTP (p = 0.033); however, patients hospitalised for TTP/SLE had a higher risk of death than lupus patients hospitalised for other causes

Conclusions

Lymphopenia is an independent risk factor for TTP/SLE. It is likely that patients with TTP/SLE present with less evident clinical features, so the level of suspicion must be higher to avoid delay in treatment.     

Unprovoked proximal venous thrombosis is associated with an increased risk of asymptomatic pulmonary embolism

Introduction

Pulmonary embolism (PE) is common in patients with deep venous thrombosis (DVT). The outcome of DVT with concomitant symptomatic PE is worse than the outcome of isolated DVT. The risk factors for DVT and simultaneous asymptomatic PE have not been systematically studied yet.

Aim

To evaluate the frequency and risk factors for asymptomatic PE in patients with DVT.

Patients/methods

In 155 consecutive patients with a first episode of DVT and no PE symptoms, a ventilation-perfusion lung scan was performed. Body mass index (BMI) and waist-to-hip ratio (WHR) were calculated and concentrations of D-dimer, high-sensitivity CRP (hsCRP), tissue plasminogen activator (t-PA) and troponin were measured. Laboratory tests for thrombophilia were performed.

Results

Asymptomatic PE was present in 36% of patients. No differences in gender, age, BMI and WHR were found between the patients with and without PE. PE was more common in patients with proximal DVT than in those with distal DVT (42% vs. 17%, p < 0.01), and in patients with unprovoked DVT compared to patients with provoked DVT (51% vs. 28%, p < 0.01). The risk of silent PE was the highest in patients with unprovoked proximal DVT (OR, 6.9; 95% CI, 2.3–21.0). Patients with asymptomatic PE had significantly higher values of D-dimer, hsCRP, t-PA and troponin than patients with isolated DVT.

Conclusions

Asymptomatic PE affected more than one third of patients with a first DVT. Unprovoked proximal DVT is the most important risk factor for the occurrence of silent PE.     

Genetic variants in Cell Adhesion Molecule 1 (CADM1): A validation study of a novel endothelial cell venous thrombosis risk factor

Introduction

In a protein C deficient family, we recently identified a candidate gene, CADM1, which interacted with protein C deficiency in increasing the risk of venous thrombosis (VT). This study aimed to determine whether CADM1 variants also interact with protein C pathway abnormalities in increasing VT risk outside this family.

Materials and methods

We genotyped over 300 CADM1 variants in the population-based MEGA case-control study. We compared VT risks between cases with low protein C activity (n = 194), low protein S levels (n = 23), high factor VIII activity (n = 165) or factor V Leiden carriers (n = 580), and all 4004 controls. Positive associations were repeated in all 3496 cases and 4004 controls.

Results

We found 22 variants which were associated with VT in one of the protein C pathway risk groups. After mutual adjustment, six variants remained associated with VT. The strongest evidence was found for rs220842 and rs11608105. For rs220842, the odds ratio (OR) for VT was 3.2 (95% CI 1.2-9.0) for cases with high factor VIII activity compared with controls. In addition, this variant was associated with an increased risk of VT in the overall study population (OR: 1.5, 95% CI 1.0-2.2). The other variant, rs11608105, was not associated with VT in the overall study population (OR: 1.0, 95% CI 0.8-1.1), but showed a strong effect on VT risk (OR: 21, 95% CI 5.1-88) when combined with low protein C or S levels.

Conclusions

In a population-based association study, we confirm a role for CADM1 variants in increasing the risk of VT by interaction with protein C pathway abnormalities.     

Haplotypes of TAFI gene and the risk of cerebral venous thrombosis - a case-control study

Introduction

Cerebral venous thrombosis (CVT) is an uncommon disease with some differences compared to other-site thrombosis, including a higher frequency in young people, female sex and oral contraceptive users. Thrombin-activatable fibrinolysis inhibitor (TAFI) is a regulator of fibrinolysis, whose levels are genetically controlled and its increase is associated to thrombosis. Our objective was to investigate in a case-control study the association between CVT and TAFI single nucleotide polymorphisms (SNPs) and its haplotypes in comparison to other-site venous thrombosis and controls.

Materials and Methods

Seventy two patients with CVT were compared to 143 individuals with no history of thromboembolic events (control group) and to 128 patients with deep vein thrombosis in the limbs and/or pulmonary embolism (venous thromboembolism-VTE group). SNPs were genotyped by restriction fragment length polymorphism or allele-specific PCR for F2 20210G > A, F5 1691G > A, TAFI (-1053C > T, -438G > A, 505G > A, 1040C > T and + 1542C > G).

Results

The GTC haplotype for TAFI 505G > A/1040C > T/+ 1542C > G SNPs was associated with an increased risk of CVT compared to controls [odds ratio (OR) 2.67, 95% confidence interval (CI): 1.13 - 6.34) and VTE group (OR 2.51, 95%CI: 1.07 - 8.06). The CVT risk became even more pronounced when evaluating unprovoked or hormone-related thrombosis cases: CVT compared to controls (OR 3.24, 95%CI: 1.19 - 8.82) and VTE group (OR 4.32, 95%CI: 1.27 - 14.63).

Conclusions

Our data indicate that the GTC haplotype for TAFI 505G > A/1040C > T/+ 1542C > G SNPs increased the risk of CVT in comparison to controls and VTE cases. Further studies are required to confirm our findings.     

Predictors of attempted inferior vena cava filters retrieval in a tertiary care centre

Background

Retrieval rates of optional recovery inferior vena cava (IVC) filters in US hospitals range from 11 - 70%. We conducted a retrospective study in a Canadian tertiary care centre to determine retrieval rates and predictors of filter removal.

Methods

Consecutive patients who had a retrievable IVC filter inserted or removed between January 2007 and December 2010 were identified. Data collected included baseline demographics, indications for filter insertion and removal, documentation of an IVC filter management plan, reasons for non-retrieval, complications, and death.

Results

275 patients with a median age of 60 years were followed in hospital for a median of 17 patient-days (range 1–876). Indications for filter placement were acute or prior VTE with contraindication to anticoagulation (72.4%), high risk of PE (11.3%) and primary prophylaxis (13.8%). Retrieval was attempted in 165 patients (60%) and was successful in 146 patients (53.1%). The most common reason for failed retrieval was filter thrombus. Predictors of attempted retrieval included documentation of filter plan (odds ratio [OR] 16.7; p < 0.001), surgical indication for IVC filter insertion (OR 4.8; p = 0.002), age ≤ 70 years (OR 3.8; p = 0.001), Hematology service involvement (OR 3.0; p = 0.006), and presence of metastatic cancer (OR 0.2; p = 0.001). Thrombotic complications occurred in 48 patients, including 3 patients who died of fatal PE.

Conclusion

Our filter retrieval rate is suboptimal. Improvements in follow-up documentation or a dedicated clinical service may help increase retrieval rates.     

Increased thrombin generation in splanchnic vein thrombosis is related to the presence of liver cirrhosis and not to the thrombotic event

Introduction

In recent years there have been increasing evidence associating liver disease with hypercoagulability, rather than bleeding. The aim of the study was to evaluate the haemostatic potential in patients with liver disease.

Patients and methods

We measured thrombin generation in the presence and absence of thrombomodulin in patients with portal vein thrombosis (PVT, n = 47), Budd-Chiari syndrome (BCS, n = 15) and cirrhosis (n = 24) and compared the results to those obtained from healthy controls (n = 21). Fifteen patients with PVT and 10 patients with BCS were treated with warfarin and were compared to an equal number of patients with atrial fibrillation matched for prothrombin time-international normalized ratio. We assessed resistance to thrombomodulin by using ratios [marker measured in the presence/absence of thrombomodulin].

Results

There were no differences in thrombin generation between patients on warfarin treatment and their controls. Cirrhotic patients generated more thrombin in the presence of thrombomodulin and exhibited thrombomodulin resistance compared to controls [p = 0.006 for endogenous thrombin potential (ETP) and p < 0.001 for peak thrombin and both ratios ETP and peak] and patients with non-cirrhotic PVT (p = 0.001, p = 0.006, p < 0.001, p < 0.001 for ETP, peak, ratio ETP, ratio peak, respectively). The patients with cirrhotic PVT exhibited higher ETP (p = 0.044) and peak (p = 0.02) in the presence of thrombomodulin than controls, as well as thrombomodulin resistance (ETP and peak ratios: p = 0.001).

Conclusions

Hypercoagulability and thrombomodulin resistance in patients with cirrhosis were independent of the presence of splanchnic vein thrombosis. The hypercoagulability in patients with cirrhotic PVT could have implications for considering longer or more intensive treatment with anticoagulants in this group.     

CVD risk factors are related to plasma fibrin clot properties independent of total and or γ’ fibrinogen concentration

Introduction

Cardiovascular disease (CVD) risk factors are associated with total fibrinogen concentration and/or altered clot structure. It is however, unclear whether such associations with clot structure are ascribed to fibrinogen concentration or other independent mechanisms. We aimed to determine whether CVD risk factors associated with increased total and/or γ’ fibrinogen concentration, were also associated with altered fibrin clot properties and secondly whether such associations were due to the fibrinogen concentration or through independent associations.

Materials and methods

In a plasma setting CVD risk factors (including total and γ’ fibrinogen concentration) were cross-sectionally analysed in 2010 apparently healthy black South African participants. Kinetics of clot formation (lag time, slope and maximum absorbance) as well as clot lysis times were calculated from turbidity curves.

Results

Of the measured CVD risk factors age, metabolic syndrome, C-reactive protein (CRP), high density lipoprotein (HDL)-cholesterol and homocysteine were significantly associated with altered fibrin clot properties after adjustment for total and or γ’ fibrinogen concentration. Aging was associated with thicker fibres (p = 0.004) while both metabolic syndrome and low HDL-cholesterol levels were associated with lower rates of lateral aggregation (slope), (p = 0.0004 and p = 0.0009), and the formation of thinner fibres (p = 0.007 and p = 0.0004). Elevated CRP was associated with increased rates of lateral aggregation (p = 0.002) and consequently thicker fibres (p < 0.0001). Hyperhomocysteinemia was associated with increased rates of lateral aggregation (p = 0.0007) without affecting fibre thickness.

Conclusion

Final clot structure may contribute to increased CVD risk in vivo through associations with other CVD risk factors independent from total or γ’ fibrinogen concentration.     

Risk factors for arterial thrombosis in antiphospholipid syndrome

Introduction

Antiphospholipid syndrome (APS) is associated with the risk of both arterial and venous thrombosis. However, it is not known which factors might determine the location of thrombosis.

Materials and Methods

To retrospectively characterize factors associated with the risk of arterial thrombosis in a cohort of APS patients. Analysis included laboratory and clinical criteria of APS, together with classical cardiovascular risk factors and the possible role of platelet integrin α₂β₁ (807 C/T) and α_IIbβ₃ (PI A1/2) genetic polymorphisms. We enrolled 163 APS patients (123 women and 40 men aged 21-75; mean age 43 years); 78 suffered from arterial thrombosis.

Results

There were no significant differences in the frequency or titers of different antiphospholipid antibodies with the exception of slightly increased frequency of IgG anticardiolipin antibodies (ACL) in the arterial thrombosis group. Livedo reticularis was observed significantly more often in the arterial thrombosis group, particularly in stroke patients.In univariate analysis arterial thrombosis was associated with male gender (OR-2,201; p = 0,033), arterial hypertension (OR-2,81; p = 0,002) and hypercholesterolemia (OR-3,69; p = 0,001). On multivariate analysis arterial hypertension (OR = 1,78; p = 0,008) and hypercholesterolemia (OR = 2,001; p = 0,002) remained as independent risk factors for arterial thrombosis. Platelet glycoprotein polymorphisms studied did not show any significant associations with arterial thrombosis in APS patients.

Conclusions

Among APS patients those with ACL IgG antibodies, having livedo reticularis, and suffering from hypertension an hypercholesterolemia are at the increased risk of arterial thrombosis.     

Certoparin versus UFH to prevent venous thromboembolic events in the very elderly patient: an analysis of the CERTIFY study

Introduction

There is an exponential rise of thromboembolic risk with age because of co-morbidities, immobility and pharmacotherapy. We aimed to investigate the benefits and risks of heparin prophylaxis in very elderly patients ≥ 80 years and the type of heparin used in a subgroup analysis of the CERTIFY trial.

Patients/methods

3,239 patients were randomized to 3,000 U aXa o.d. certoparin or 5,000 IU t.i.d. unfractionated heparin (UFH) for 8-20 days.

Results

Patients ≥ 80 years (n = 1,365) were more likely to be female, had a lower mean bodyweight, were more frequently using antiplatelets and had a GFR below 30 ml/min/1.73 m² more often than patients < 80 years (n = 1,875). The combined endpoint of proximal DVT, symptomatic non-fatal PE and VTE related death was experience by 5.26% of patients ≥ 80 years versus 3.51% in younger patients (OR 1.53; 95%CI 1.05-2.21; p = 0.03). There were no significant differences in both minor (OR 1.11; 95%CI 0.75-1.62) and major (OR 2.53; 95%CI 0.93-6.86) bleeding risks. Certoparin and UFH were equally effective in reducing thromboembolic risk in either age group. The risk of any (OR 0.45; 95%CI 0.26-0.79) and minor bleeding (OR 0.42; 95%CI 0.23-0.78) was reduced with certoparin in the very elderly only. There were more adverse events in elderly patients (OR 1.26; 95%CI 1.1-1.46), but rates were otherwise comparable.

Conclusions

The analysis confirmed the increased thromboembolic risk in very elderly patients, but demonstrated no increased bleeding risk. Certoparin and UFH were equally effective and safe with a reduced risk of minor bleeding complications with certoparin in the very elderly.     

Influence of TAAR6 polymorphisms on response to aripiprazole

Background

There is some evidence suggesting a role of TAAR6 in schizophrenia. The aim of the present study is to investigate possible influences of a panel of markers in TAAR6 (rs8192625, rs4305745, rs4305746, rs6903874, rs6937506) on clinical outcomes and side effects in a sample of Korean schizophrenic aripiprazole treated patients.

Methods

Efficacy was assessed at baseline and weeks 1, 2, 4, 6, 8 using CGI-S, CGI-I, BPRS and SANS. Side effects were evaluated through SAS, BAS and AIMS. Multivariate analysis of covariance (MANCOVA) was used to test possible influences of single SNPs on clinical and safety scores. Tests for associations using multi-marker haplotypes were performed using the statistics environment “R”.

Results

A significant time per genotype interaction was found between rs4305746 in repeated measures of ANOVA on BPRS scores (F = 2.45, df = 10,365, p = 0.008). In particular G/A and A/A genotype patients were more likely to improve over time as compared to carriers of the G/G genotype. Permutation analysis confirmed a significant effect of rs4305746 on course of BPRS scores over time (p = 0.007). Haplotype analysis did not reveal any significant association with clinical and safety scores at any time.

Conclusion

A possible association could exist between some genotypes in TAAR6 and response to aripiprazole. However, several limitations characterize the present work, such as small sample size, the finding related to a single scale and the possibility of false positive findings, thus further investigation is required.     

The predictive value of heart-type fatty acid-binding protein is independent from symptom duration in normotensive patients with pulmonary embolism

Background

Heart-type fatty acid-binding protein (H-FABP) is a useful biomarker for risk stratification of patients with pulmonary embolism (PE). In patients with acute myocardial infarction, H-FABP plasma concentrations rise after 30 minutes and return to normal within 20-24 hours. We tested whether the predictive value of H-FABP is affected by the duration of symptoms prior to diagnosis in patients with PE.

Material and Methods

We prospectively studied 257 consecutive normotensive patients with confirmed symptomatic PE.

Results

Patients with acute (< 24 hours; n = 150) symptom onset presented more often with syncope (28.7% vs. 6.5%; p < 0.001) compared to patients with symptoms ≥ 24 hours (n = 107); other baseline characteristics, comorbidities, and risk factors were distributed equally. Patients with an adverse 30-day outcome (6.6%) had higher H-FABP levels (11.84 [3.57-19.62] ng/ml) compared to patients with a favorable course (3.42 [1.92-5.42] ng/ml; p < 0.001). However, the proportion of patients with H-FABP levels ≥ 6 ng/ml did not differ among patients with acute symptom onset and late presentation (p = 0.104). Only tachycardia and elevation of H-FABP were associated with an increased risk of an adverse 30-day outcome both in patients with acute symptom onset (H-FABP: OR, 5.8; 95% CI, 1.4-24.5; p = 0.016; tachycardia: 7.0 [1.4-36.0]; p = 0.018) and late presentation (H-FABP: 9.3 [2.0-43.2]; p = 0.004 and tachycardia: 12.3 [1.5-103.6]; p = 0.021). The prognostic value could further be improved by the use of a simple H-FABP-based clinical prediction score.

Conclusions

Our findings indicate that H-FABP is a useful biomarker for risk stratification of normotensive patients with PE regardless of symptom duration prior to diagnosis.     

The association of the JAK2 46/1 haplotype with non-splanchnic venous thrombosis

Background

The inherited JAK2 46/1 haplotype is strongly associated with the development of myeloproliferative neoplasms (MPNs), and its increased frequency has also been reported in splanchnic venous thrombosis (SVT). In the present study, the role of the JAK2 46/1 haplotype in non-splanchnic venous thrombosis (non-SVT) was investigated.

Methods and Results

We genotyped 438 patients with non-SVT, 226 patients with MPNs and 459 healthy controls for three single nucleotide polymorphisms (SNPs) which tag the JAK2 46/1 haplotype (rs12342421 G > C, rs12343867 T > C and rs10974944 C > G). We found statistically significant association of the rs12342421 GC + CC genotypes (OR = 1.40; p = 0.023) and the rs12343867 TC + CC genotypes (OR = 1.83; p = 7.02x10^- 5) with non-SVT. We also found that the CC haplotype of these two SNPs was associated with an increased risk of the disease (OR = 1.68; p = 0.009). Stratification analysis indicated that the observed association of the JAK2 46/1 haplotype with non-SVT was probably largely free of confounding effect of thrombophilic risk factors. In addition, we established a strong association of SNPs rs12342421 and rs10974944 and their CG haplotype with MPNs and with JAK2 V617F-positive MPNs.

Conclusions

This study provides statistical evidence that SNPs rs12342421 and rs12343867 are associated with an increased risk of non-SVT. Consistently, haplotypes of the SNPs were also associated with non-SVT risk, suggesting that inherited genetic variation in the JAK2 gene may play a role in the pathogenesis of non-SVT. Furthermore, the reported associations of the JAK2 46/1 haplotype with MPNs as well as with the occurrence of the JAK2 V617F mutation in MPNs were confirmed.     

The role of soluble P selectin in the diagnosis of venous thromboembolism

Introduction

Soluble P selectin (sPsel), a member of the selectin family of cell adhesion receptors, has been proposed as a key molecule in hemostasis and thrombosis mediating platelet rolling, generating procoagulant microparticles and enhancing fibrin deposition. The aim of this study was to examine the role of sPsel in the diagnosis of venous thromboembolism (VTE).

Materials and Methods

We performed a systematic review and we used meta-analysis to synthesize data from published studies reporting sPsel levels in patients with i) VTE (deep venous thrombosis; DVT or DVT and pulmonary embolism; PE) and ii) DVT only. Pooled Odds Ratios (ORs) with 95% Confidence Intervals (CIs) were appropriately calculated among patients and controls. Diagnostic performance of sPsel was tested with pooled sensitivity, specificity, Diagnostic Odds Ratio (DOR) and summary receiver operator characteristic (SROC) curve.

Results

Eleven studies, comprising of 586 VTE patients and 1,843 controls were deemed eligible. The sPsel was significantly increased after VTE (OR = 2.89, 95%CI = 2.31-3.61, p < 0.001), or DVT only (OR = 2.64, 95%CI = 1.95-3.56, p < 0.001). Subgroup analysis evidenced that sPsel was also increased after VTE when evaluating only studies with patients that had no prior medical history (OR = 2.88, 95%CI = 1.98-4.19, p < 0.001). Exclusion of studies including patients with solid organ tumor, HIV or lupus anticoagulants positive patients did not alter findings. Pooled sensitivity and specificity of sPsel was 0.57 (95%CI = 0.30-082, p < 0.001) and 0.73 (95%CI = 0.51-0.90, p < 0.001), respectively and DOR was 4.31 (95%CI = 2.22-8.37, p < 0.01). SROC curve yielded in significant accuracy of sPsel performance (AUC = 0.74, p = 0.05).

Conclusions

The sPsel was significantly elevated in patients with DVT, both uncomplicated and complicated with PE and presented with high levels of diagnostic performance. sPsel is a plasma biomarker that may help in the diagnosis of VTE.     

Genetic determinants of acenocoumarol and warfarin maintenance dose requirements in Slavic population: A potential role of CYP4F2 and GGCX polymorphisms

Introduction

VKORC1 and cytochrome CYP2C9 genetic variants contribute largely to inter-individual variations in vitamin K antagonists (VKAs) dose requirements. Cytochrome P450 4 F2 isoform (CYP4F2), gamma-glutamyl carboxylase (GGCX) and apolipoprotein E (APOE) polymorphisms have been suggested to be of minor significance.

Materials and Methods

We sought to assess the impact of those polymorphisms on dose requirements in Central-Eastern European cohort of 479 patients receiving acenocoumarol (n = 260) or warfarin (n = 219).

Results

There were no differences between the acenocoumarol and warfarin groups with regard to the gender, age, body mass index and international normalized ratio. The VKORC1 c.-1639A allele carriers required a lower dose of acenocoumarol and warfarin than the non-carriers (28.0 [21.0–35.0] vs. 42.0 [28.0–56.0] mg/week, p < 0.0001; 35.0 [28.0–52.0] vs. 52.0 [35.0–70.0] mg/week, p = 0.0001, respectively). Carriers of *2 and/or *3 variant alleles for CYP2C9 also required a lower dose of warfarin as compared with *1*1 carriers (35.0 [31.5–52.5] vs. 43.8 [35.0–60.2] mg/week, p = 0.02; 35.0 [23.5–35.0] vs. 43.8 [35.0-60.2] mg/week, p < 0.0001, respectively). Similarly, possession of G allele of GGCX c.2084 + 45 polymorphism was associated with lower warfarin dose (35.0 [26.3–39.2] vs. 45.5 [35.0–65.1] mg/week, p = 0.03). No effect of CYP2C9*2,-*3 and GGCX c.2084 + 45G > C polymorphisms on acenocoumarol dosage was observed. Interestingly, carriers of CYP4F2 c.1297A variant required a higher dose of acenocoumarol and warfarin than non-carriers (43.8 [35.0–60.2] vs. 35.0 [35.0–52.5] mg/week, p = 0.01; 35.0 [28.0–52.5] vs. 28.0 [28.0–42.0] mg/week, p = 0.05).

Conclusions

We have shown for the first time, that besides VKORC1 and CYP2C9 genetic variants, the CYP4F2 c.1297A and GGCX c.2084 + 45G have a moderate effect on VKAs dose requirements in Slavic population from Central-Eastern Europe.