scholarly journals Evidence for increased risk of venous thrombosis during air travel

2000 ◽  
Vol 2 (1) ◽  
Author(s):  
Joanna Lyford
Keyword(s):  
Venous Thrombosis ◽  
Air Travel ◽  
Increased Risk

Special Groups

2012 ◽  
Author(s):  
Dom Colbert
Keyword(s):  
Glycaemic Control ◽  
Venous Thrombosis ◽  
Common Sense ◽  
Young Male ◽  
Casual Sex ◽  
Air Travel ◽  
Poor Glycaemic Control ◽  
Special Groups ◽  
Increased Risk ◽  
Overseas Travel

It is convenient to separate those who differ from the general travelling population into easily identifiable categories or special groups. Each of these groups will require advice, medication, or vaccines that are tailored for their specific needs. Thus, the pregnant traveller must be warned of the increased risk of air-travel-related venous thrombosis, the diabetic of the danger of poor glycaemic control, and the young (male) traveller of the risks of casual sex. While there are very few people for whom overseas travel is absolutely contraindicated, common sense should always be heeded.

scholarly journals Haemostatic and thrombo-embolic complications in pregnant women with COVID-19: a systematic review and critical analysis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Juliette Servante ◽  
Gill Swallow ◽  
Jim G. Thornton ◽  
Bethan Myers ◽  
Sandhya Munireddy ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Pregnant Women ◽  
Clinical Evidence ◽  
Case Reports ◽  
Standard Form ◽  
Test Results ◽  
Maternal Deaths ◽  
High Clinical Suspicion ◽  
Increased Risk ◽  
Definition Of

Abstract Background As pregnancy is a physiological prothrombotic state, pregnant women may be at increased risk of developing coagulopathic and/or thromboembolic complications associated with COVID-19. Methods Two biomedical databases were searched between September 2019 and June 2020 for case reports and series of pregnant women with a diagnosis of COVID-19 based either on a positive swab or high clinical suspicion where no swab had been performed. Additional registry cases known to the authors were included. Steps were taken to minimise duplicate patients. Information on coagulopathy based on abnormal coagulation test results or clinical evidence of disseminated intravascular coagulation (DIC), and on arterial or venous thrombosis, were extracted using a standard form. If available, detailed laboratory results and information on maternal outcomes were analysed. Results One thousand sixty-three women met the inclusion criteria, of which three (0.28, 95% CI 0.0 to 0.6) had arterial and/or venous thrombosis, seven (0.66, 95% CI 0.17 to 1.1) had DIC, and a further three (0.28, 95% CI 0.0 to 0.6) had coagulopathy without meeting the definition of DIC. Five hundred and thirty-seven women (56%) had been reported as having given birth and 426 (40%) as having an ongoing pregnancy. There were 17 (1.6, 95% CI 0.85 to 2.3) maternal deaths in which DIC was reported as a factor in two. Conclusions Our data suggests that coagulopathy and thromboembolism are both increased in pregnancies affected by COVID-19. Detection of the former may be useful in the identification of women at risk of deterioration.

Abstract WP179: Rate of Pulmonary Embolism After Cerebral Venous Thrombosis

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Ava L Liberman ◽  
Alexander E Merkler ◽  
Gino Gialdini ◽  
Michael P Lerario ◽  
Steven R Messe ◽  
...  
Keyword(s):  
Risk Factors ◽  
Pulmonary Embolism ◽  
Venous Thrombosis ◽  
Vascular Risk Factors ◽  
Emergency Department Visits ◽  
Administrative Claims ◽  
Cerebral Vein ◽  
Vascular Risk ◽  
Index Hospitalization ◽  
Increased Risk

Introduction: Cerebral vein thrombosis (CVT) is associated with an increased risk of subsequent venous thromboembolism. It is unknown whether the risk of pulmonary embolism (PE) after CVT is similar to that of PE after deep venous thrombosis (DVT). Methods: We performed a retrospective cohort study using administrative claims data from all emergency department visits and hospitalizations in California from 2005-2011, New York from 2006-2013, and Florida from 2005-2013. We identified patients with CVT or DVT as well as the primary outcome of PE using previously validated International Classification of Diseases, Ninth Revision, Clinical Modification ( ICD-9-CM ) codes. In order to minimize misclassification error, patients with both CVT and DVT during the same index hospitalization were excluded and patients with CVT were censored at the time of development of DVT and vice versa. Kaplan-Meier survival statistics and Cox proportional hazards models were used to compare the risk of PE after CVT versus after DVT while adjusting for demographics, vascular risk factors, and the Elixhauser comorbidity index. Results: We identified 4,450 patients with CVT and 217,589 patients with DVT. During a mean follow-up of 2.0 (±1.7) years, 124 patients with DVT developed a PE and 18,698 patients with DVT developed a PE. Patients with CVT were younger (mean age 45 vs 63), more often female (71% vs 52%), more often pregnant, and had fewer vascular risk factors than patients with DVT. During the index hospitalization, the rate of PE was 1.5% (95% confidence interval [CI], 1.1-1.8%) in patients with CVT and 6.2% (95% CI, 6.1-6.3%, p<0.001) in patients with DVT. By 5 years, the cumulative rate of PE after CVT was 3.7% (95% CI, 3.0-4.4%) compared to 10.5% (95% CI, 10.3-10.6%, p<0.001) after DVT. After adjustment for demographics and comorbidities, CVT was associated with a significantly lower hazard of PE when compared to DVT (hazard ratio, 0.31; 95% CI, 0.26-0.38). Conclusion: In a large, heterogeneous population, we found that the risk of PE after CVT was significantly lower than that of PE after DVT. Among patients with CVT, the greatest risk for PE was apparent during the index hospitalization.

Decreased anticoagulant response to tissue factor pathway inhibitor in patients with venous thromboembolism and otherwise no evidence of hereditary or acquired thrombophilia

2004 ◽  
Vol 91 (01) ◽  
pp. 80-86 ◽  
Author(s):  
Brigitte Piccapietra ◽  
Johanna Boersma ◽  
Joerg Fehr ◽  
Thomas Bombeli
Keyword(s):  
Venous Thromboembolism ◽  
Venous Thrombosis ◽  
Mean Value ◽  
Healthy Controls ◽  
Crude Odds Ratio ◽  
Sensitivity Ratio ◽  
Increased Risk ◽  
History Of ◽  
Anticoagulant Response ◽  
Acquired Thrombophilia

SummaryNo relevant deficiency of TFPI or genetic polymorphisms could thus far consistently be associated with venous thromboembolism. We hypothesized that the substrates of the TFPI protein, including FVII or FX (rather than the protein itself) could induce a hypercoagulable state. We created a novel TF-based clotting assay that evaluated the anticoagulant response to exogenously added recombinant TFPI. The response to TFPI was expressed as the ratio of the clotting time with and without TFPI. By using 118 healthy controls, we established a reference range between 1.31 and 1.93 (mean value ± 2 standard deviations (SD), 1.62 ± 0.31). We then evaluated samples from 120 patients with a history of venous thromboembolism but no evidence of hereditary and acquired thrombophilia. The range of the patients’ ratios was significantly (P < 0.001) lower, falling between 1.2 and 1.78 (mean value ± 2 SD, 1.49 ± 0.29). Of the 120 patients, 39 (32.5%) had a TFPI sensitivity ratio below the 10th percentile of the controls, compared with 11 (9.3%) of the healthy controls. The crude odds ratio for venous thrombosis for subjects with a TFPI sensitivity ratio below the 10th percentile was 13 (95% CI; range, 3.1 to 54.9) compared with those with a ratio above 1.8 (90th percentile). Patients with idiopathic thromboembolism did not have a decreased TFPI sensitivity ratio more often than patients with thrombosis with a circumstantial risk factor. Based on these results, a reduced response to TFPI may lead to an increased risk of venous thrombosis.

Polymorphisms in the protein C gene as risk factor for venous thrombosis

2009 ◽  
Vol 101 (01) ◽  
pp. 62-67 ◽  
Author(s):  
Carine Doggen ◽  
Hans Vos ◽  
Pieter Reitsma ◽  
Frits Rosendaal ◽  
Elisabeth Pomp
Keyword(s):  
Oral Contraceptive ◽  
Venous Thrombosis ◽  
Protein C ◽  
Contraceptive Use ◽  
Factor V Leiden ◽  
Factor V ◽  
Thrombotic Risk ◽  
Control Subjects ◽  
Oral Contraceptive Use ◽  
Increased Risk

SummaryProtein C is an important inhibitor of blood coagulation. We investigated the effect of two polymorphisms within the promoter region of the protein C gene (C/T at position 2405 and A/G at position 2418) on risk of venous thrombosis and on plasma protein C levels. In addition the combined effect of the two polymorphisms with factor V Leiden and oral contraceptive use was investigated. Previous studies on these polymorphisms were small and were not able to investigate synergistic effects. In the Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis (MEGA study), protein C levels were determined in 2,043 patients with venous thrombosis and 2,857 control subjects, and the two polymorphisms in 4,285 patients and 4,863 control subjects. The CC/GG genotype was associated with the lowest protein C levels. Compared to carriers of the TT/AA genotype – a genotype associated with higher protein C levels – the risk of venous thrombosis in CC/GG carriers was 1.3-fold increased (95% confidence interval 1.09–1.48). The combination of factor V Leiden with the CC/GG genotype led to a 4.7-fold increased risk, compared to non-carriers with the TT/AA genotype. Oral contraceptive use together with the CC/ GG genotype resulted in a 5.2-fold increased risk. In conclusion, the CC/GG genotype is associated with lower levels of protein C and an elevated risk of venous thrombosis compared to the TT/AA genotype. There is no clear synergistic effect of the CC/ GG genotype with factor V Leiden or oral contraceptive use on thrombotic risk.

scholarly journals Antiphospholipid antibodies and thrombosis: association with acquired activated protein C resistance in venous thrombosis and with hyperhomocysteinemia in arterial thrombosis

2004 ◽  
Vol 92 (12) ◽  
pp. 1312-1319 ◽  
Author(s):  
Jeannine Kassis ◽  
Carolyn Neville ◽  
Joyce Rauch ◽  
Lambert Busque ◽  
Erika Chang ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Antiphospholipid Antibodies ◽  
Arterial Thrombosis ◽  
Protein C ◽  
Complete Blood Count ◽  
Tertiary Care ◽  
Activated Protein C ◽  
Factor V Leiden ◽  
Activated Protein C Resistance ◽  
Increased Risk

SummaryAlthough antiphospholipid antibodies (aPL) are associated with thrombosis, it is not known who with aPL is at higher risk for thrombosis. It was the aim of this cross-sectional study to investigate how thrombophilic factors contribute to venous or arterial thrombosis in aPL-positive individuals. In outpatient test centres at two tertiary care hospitals, two hundred and eight (208) persons requiring aPL testing were matched by age, gender and centre to 208 persons requiring a complete blood count. Persons were classified as aPL-positive (having anticardiolipin, lupus anticoagulant and/or anti-β2-glycoprotein I antibodies) or aPL-negative. Several thrombophilic factors were studied using logistic regression modelling. Results showed that the aPL-positive group had three-fold more events (37%) than the aPL-negative group (12%). In unadjusted analyses, clinically important associations were observed between factor V Leiden and venous thrombosis, hyperhomocysteinemia and arterial thrombosis, and activated protein C resistance (APCR) and venous thrombosis (OR, 95% CI = 4.00, 1.35-11.91; 4.79, 2.03-11.33; and 2.03, 1.03-3.97, respectively). After adjusting for recruitment group, persons with both APCR and aPL had a three-fold greater risk (OR, 95% CI = 3.31, 1.30-8.41) for venous thrombosis than those with neither APCR nor aPL. Similarly, after adjusting for hypertension, family history of cardiovascular disease, gender and recruitment group, persons with both hyperhomocysteinemia and aPL had a five-fold increased risk (OR, 95% CI = 4.90, 1.37-17.37) for arterial thrombosis compared to those with neither risk factor. In conclusion, APCR phenotype and hyperhomocysteinemia are associated with a higher risk of venous and arterial thrombosis, respectively, in the presence of aPL.

scholarly journals Association of ABO haplotypes with the risk of venous thrombosis: impact on disease risks estimation

Blood ◽  
2020 ◽  
Author(s):  
Louisa Goumidi ◽  
Florian Thibord ◽  
Kerri L. Wiggins ◽  
Ruifang Li-Gao ◽  
Michael R Brown ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Blood Group ◽  
Plasma Levels ◽  
Odds Ratio ◽  
Prediction Models ◽  
Genetic Risk Score ◽  
Individual Risk ◽  
Abo Blood Group ◽  
Increased Risk ◽  
The Impact

Genetic risk score (GRS) analysis is an increasingly popular approach to derive individual risk prediction models for complex diseases. In the context of venous thrombosis (VT), any GRS shall integrate information at the ABO blood group locus, the latter being one of the major susceptibility locus for this disease. However, there is yet no consensus about which single nucleotide polymorphisms (SNPs) must be investigated when one is interested in properly assessing the association of ABO locus with VT risk. Using comprehensive haplotype analyses of ABO blood group tagging SNPs in up to 5,425 cases and 8,445 controls from 6 studies, we demonstrated that using only rs8176719 (tagging O1) to correctly assess the impact of ABO locus on VT risk is suboptimal as 5% of rs8176719-delG carriers are not exposed at higher VT risk. Instead, we recommend to use 4 SNPs, rs2519093 (tagging A1), rs1053878 (A2), rs8176743 (B) and rs41302905 (O2) in any analysis aimed at assessing the impact of ABO locus on VT risk to avoid any risk misestimation. Compared to O1 haplotype that can be inferred from these 4 SNPs, the A2 haplotype is associated with a modest increase in VT risk (odds ratio ~1.2), A1 and B haplotypes are associated with a ~1.8 fold increased risk while O2 tend to be slightly protective (odds ratio ~0.80). In addition, our analyses clearly showed that while the A1 an B blood group are associated with increased vWF and FVIII plasma levels only the A1 blood group is associated wih ICAM plasma levels but in an opposite direction, leaving additional avenues to be explored in order to fully understand the whole spectrum of biological effect of ABO locus on cardiovascular traits.

scholarly journals Systematic Review of Hormonal Contraception and Risk of Venous Thrombosis

2018 ◽  
Vol 85 (4) ◽  
pp. 470-477 ◽  
Author(s):  
Lynn Keenan ◽  
Tyson Kerr ◽  
Marguerite Duane ◽  
Karl Van Gundy
Keyword(s):  
United States ◽  
Venous Thrombosis ◽  
Ethinyl Estradiol ◽  
Hormonal Contraception ◽  
The United States ◽  
Comparable Efficacy ◽  
Healthy Women ◽  
Increased Risk ◽  
Blood Clots ◽  
The World

Background: Hormonal contraception (HC) is widely used throughout the world and has been associated with venous thrombosis (VT) such as deep vein thrombosis, pulmonary emboli, and cerebral VT. Objectives: To provide a current comprehensive overview of the risk of objectively confirmed VT with HC in healthy women compared to nonusers. Search methods: PubMed was searched from inception to April 2018 for eligible studies in the English language, with hand searching from past systematic reviews. Selection criteria: We selected original research evaluating risk of objectively confirmed VT in healthy women taking oral or nonoral HC compared with nonusers. Data collection: The primary outcome of interest was a fatal or nonfatal VT in users of HC compared to nonusers or past users. Studies with at least twenty events were eligible. Adjusted relative risks with 95 percent confidence intervals were reported. Three independent reviewers extracted data from selected studies. Results: 1,962 publications were retrieved through the search strategy, with 15 publications included. Users of oral contraception with levonorgesterol had increased risk of VT by a range of 2.79–4.07, while other oral hormonal preparations increased risk by 4.0–48.6. Levonorgestrel intrauterine devices did not increase risk. Etonogestrel/ethinyl estradiol vaginal rings increased the risk of VT by 6.5. Norelgestromin/ethinyl estradiol patches increased risk of VT by 7.9. Etonogestrel subcutaneous implants by 1.4 and depot-medroxyprogesterone by 3.6. The risk of fatal VT was increased in women aged fifteen to twenty-four by 18.8-fold. Conclusion: Users of HC have a significant increased risk of VT compared to nonusers. Current risks would project at least 300–400 healthy young women dying yearly in the United States due to HC. Women should be informed of these risks and offered education in fertility-awareness-based methods with comparable efficacy for family planning. Summary: HC is widely used throughout the world and has been associated with blood clots in the legs and lungs. We searched the literature and found the risks of currently used forms of birth control increased between three- and ninefold for blood clots for healthy women. The risks found would project 300–400 women dying from using HC each year in the United States.

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

Hematology ◽  
2005 ◽  
Vol 2005 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Frits R. Rosendaal
Keyword(s):  
Risk Factors ◽  
Venous Thrombosis ◽  
Protein S ◽  
Behavioral Risk ◽  
Antithrombin Deficiency ◽  
Increased Risk ◽  
Environment And Behavior ◽  
And Behavior ◽  
Subsequent Identification

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

Sign in / Sign up

Export Citation Format

Share Document