Family history of venous thromboembolism (VTE) and risk of recurrent hospitalization for VTE: a nationwide family study in Sweden

A combination of strongly associated prothrombotic single nucleotide polymorphisms could efficiently predict venous thrombosis risk

Background

Venous thrombosis (VT) is multifactorial trait that contributes to the global burden of cardiovascular diseases. Although abundant single nucleotide polymorphisms (SNPs) provoke the susceptibility of an individual to VT, research has found that the five most strongly associated SNPs, namely, rs6025 (F5 Leiden), rs2066865 (FGG), rs2036914 (F11), rs8176719 (ABO), and rs1799963 (F2), play the greatest role. Association and risk prediction models are rarely established by using merely the five strongly associated SNPs. This study aims to explore the combined VT risk predictability of the five SNPs and well-known non-genetic VT risk factors such as aging and obesity in the Hungarian population.

Methods

SNPs were genotyped in the VT group (n = 298) and control group (n = 400). Associations were established using standard genetic models. Genetic risk scores (GRS) [unweighted GRS (unGRS), weighted GRS (wGRS)] were also computed. Correspondingly, the areas under the receiver operating characteristic curves (AUCs) for genetic and non-genetic risk factors were estimated to explore their VT risk predictability in the study population.

Results

rs6025 was the most prevalent VT risk allele in the Hungarian population. Its risk allele frequency was 3.52-fold higher in the VT group than that in the control group [adjusted odds ratio (AOR) = 3.52, 95% CI: 2.50-4.95]. Using all genetic models, we found that rs6025 and rs2036914 remained significantly associated with VT risk after multiple correction testing was performed. However, rs8176719 remained statistically significant only in the multiplicative (AOR = 1.33, 95% CI: 1.07-1.64) and genotypic models (AOR = 1.77, 95% CI: 1.14-2.73). In addition, rs2066865 lost its significant association with VT risk after multiple correction testing was performed. Conversely, the prothrombin mutation (rs1799963) did not show any significant association. The AUC of Leiden mutation (rs6025) showed better discriminative accuracy than that of other SNPs (AUC = 0.62, 95% CI: 0.57-0.66). The wGRS was a better predictor for VT than the unGRS (AUC = 0.67 vs. 0.65). Furthermore, combining genetic and non-genetic VT risk factors significantly increased the AUC to 0.89 with statistically significant differences (Z = 3.924, p < 0.0001).

Conclusions

Our study revealed that the five strongly associated SNPs combined with non-genetic factors could efficiently predict individual VT risk susceptibility. The combined model was the best predictor of VT risk, so stratifying high-risk individuals based on their genetic profiling and well-known non-modifiable VT risk factors was important for the effective and efficient utilization of VT risk preventive and control measures. Furthermore, we urged further study that compares the VT risk predictability in the Hungarian population using the formerly discovered VT SNPs with the novel strongly associated VT SNPs.

Investigation of the association of the RAN (rs14035) and XPO5 (rs11077) polymorphisms with venous thromboembolism

INTRODUCTION

Venous thromboembolism (VTE) is the third most common hemostatic disease worldwide. Studies have reported a role for microRNA (miRNA) in the homeostasis and development of VTE. The ras-related nuclear protein (RAN) and exportin 5 (XPO5) genes are involved in miRNA biogenesis, as both regulate the transport of pre-miRNA from the nucleus to the cytoplasm. Therefore, the aim of the current study is to examine the association between RAN (rs14035) and XPO5 (rs11077) single nucleotide polymorphisms (SNPs) and VTE.

METHODS

The study sample consisted of 300 subjects (150 patients and 150 age and sex matched controls). The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and tetra-primer amplification refractory mutation system (T-ARMS) techniques were used to genotype rs14035 and rs11077, respectively.

RESULTS

The results showed that there was a significant association between the XPO5 rs11077 and the risk of VTE (P < 0.05). Subjects with AC (OR: 2.08, CI:1.26-3.44) and CC (OR: 1.77, CI: 0.88-3.55) genotypes were at increased risk of the developing VTE. Regarding RAN gene, no association was found between rs14035 and VTE (P > 0.05). In addition, no associations were found between XPO5 rs11077 and RAN rs14035 genotypes with blood cell parameters (P > 0.05). As for the demographic characteristics, the results indicated a strong association between family history and body mass index (BMI) with the risk of VTE (P < 0.01).

CONCLUSION

The XPO5 rs11077, BMI and family history might contribute to the development of VTE in Jordan.

Current Knowledge on Factor V Leiden Mutation as a Risk Factor for Recurrent Venous Thromboembolism: A Systematic Review and Meta-Analysis

Background

Thrombophilia screening is widely done in clinical practice, and it is claimed that the extent of venous thromboembolism (VTE) recurrence risk in patients with common defects is still not fully understood.

Aim

We aimed to summarize data of all observational studies prospectively assessing the association of heterozygous factor V Leiden (FVL) mutation and recurrent VTE in patients with VTE, and to calculate pooled relative risks (RR), overall and in various subgroups.

Methods

We searched MEDLINE and EMBASE databases for cohort studies prospectively assessing VTE recurrence in patients with and without FVL mutation (PROSPERO: CRD42021182800). Data were extracted on cohort and study-level. The methodological quality was assessed using the Newcastle-Ottawa Scale (NOS). RR were calculated overall and in subgroups using a random-effects model.

Results

From 31 cohorts, 24 studies were finally included summarizing 13,571 patients. Heterozygous FVL mutation was identified in 2,840 individuals (21%). The methodological quality was estimated to be high in 20 studies (83%). The overall RR was 1.46 (95% CI: 1.31, 1.64), consistent across subgroups.

Conclusions

Pooling all high-quality epidemiological data, the risk of recurrent VTE was increased by 46% in patients with heterozygous FVL mutation. Against the background of established risk factors, the FVL mutation plays only a marginal role in the risk assessment for recurrent VTE.

Do Patients with a Family or Personal History of Venous Thromboembolism have an Increased Risk of Recurrence?

BACKGROUND

 A family (FH) and personal history (PH) of venous thromboembolism (VTE) are commonly evaluated risk factors for recurrence. We examined the association between FH/PH of VTE and the risk of recurrence and whether a stronger history status (i.e., both FH/PH vs. no FH/PH) carries an increased recurrence risk.

METHODS

 We prospectively followed 813 patients aged ≥ 65 years with acute VTE from 9 Swiss hospitals. We classified patients into four groups: no FH/PH, FH only, PH only, and both FH/PH. The primary outcome was recurrent VTE during the full observation period. We examined the association between FH/PH status and the time to VTE recurrence using competing risk regression, adjusting for confounders and periods of anticoagulation.

RESULTS

 Of 813 patients with VTE, 59% had no FH/PH, 11% a FH only, 24% a PH only, and 7% had both a FH and PH of VTE. Overall, 105 patients had recurrent VTE during the full observation period. After adjustment, patients with a FH only (subhazard ratio [SHR] 0.8, 95% confidence interval [CI] 0.4-1.7), PH only (SHR 1.5, 95% CI 0.9-2.5), and both FH/PH (SHR 1.4, 95% CI 0.6-3.1) did not have an increased risk of recurrent VTE compared with those without FH/PH. When we considered the period after the completion of initial anticoagulation only, the results were similar.

CONCLUSION

 Our findings indicate that in patients with acute VTE, a FH and/or PH of VTE does not convey an increased risk of recurrent VTE. In particular, we did not find a "dose-effect" relationship between FH/PH status and VTE recurrence.

The Higher Prevalence of Venous Thromboembolism in the Hungarian Roma Population Could Be Due to Elevated Genetic Risk and Stronger Gene-Environmental Interactions

Background: Interactions between genetic and environmental risk factors (GxE) contribute to an increased risk of venous thromboembolism (VTE). Understanding how these factors interact provides insight for the early identification of at-risk groups within a population and creates an opportunity to apply appropriate preventive and curative measures.

Objective: To estimate and compare GxE for VTE risk in the general Hungarian and Roma populations.

Methods: The study was based on data extracted from a database consisting of results previously obtained from a complex health survey with three pillars (questionnaire-based, physical, and laboratory examinations) involving 406 general Hungarian and 395 Roma subjects. DNA was genotyped for rs121909567 (SERPINC1), rs1799963 (F2), rs2036914 (F11), rs2066865 (FGG), rs6025 (F5), and rs8176719 (ABO) polymorphisms. After allele frequency comparisons, the odds ratio (OR) was calculated for individual SNPs. Furthermore, genetic risk scores (weighted GRS, unweighted GRS) were computed to estimate the joint effect of the genetic factors. Multivariable linear regression analysis was applied to test the impact of GxE on VTE risk after interaction terms were created between genetic and VTE risk factors [diabetes mellitus (DM), cancer, chronic kidney diseases (CKD), coronary artery diseases (CAD), migraine, depression, obesity, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high density lipoprotein (HDL-C), triglyceride (TG), and smoking].

Results: Interestingly, the rs121909567 (SERPINC1, ATBp3 mutation) SNP was not present in the general population at all. However, the risk allele frequency was 1% among the Roma population, which might suggest a founder effect in this minority. This polymorphism multiplicatively interacted with CAD, CKD, cancer, DM, depression, migraine, and obesity. Even though interactions were not statistically significant, the trend of interaction showed the probability of an incremental VTE risk among the Roma population. The risk of VTE was 4.7 times higher (p > 0.05) for Roma subjects who had ≥3 wGRS (median value) compared with individuals having lower wGRS values but lower for the general subjects (OR = 3.1 × 10⁻⁸). Additionally, the risk of VTE was 6.6 times higher in the Roma population that had ≥3 risk alleles (median value) than in individuals with the 0–1 risk allele, and the overall risk was much higher for the Roma population (OR = 6.6; p > 0.05) than for the general Hungarian population (OR = 1.5; p > 0.05). Five positive and significant GxE interactions were identified in the Roma population. The risk of VTE was higher among depressive Roma subjects who carried the risk variant rs2036914 (β = 0.819, p = 0.02); however, this interaction was not significant for the general subjects. The joint presence of high levels of LDL-C and rs2066865 (FGG) increased the VTE risk only among Roma individuals (β = 0.389, p = 0.002). The possibility of VTE risk increment, as a result of a multiplicative interaction between rs8176719 (ABO) and cancer, was identified, which was higher for the Roma population (β = 0.370, p < 0.001) than for the general population (β = −0.042, p = 0.6). The VTE risk increased in the Roma population (β = 0.280, p = 0.001), but was higher in the general population (β = 0.423, p = 0.001) as a result of the multiplicative interaction between CAD and rs2036914 (F11). The presence of a multiplicative interaction between rs2066865 (FGG) and CAD increased the VTE risk for the Roma population (β = 0.143, p = 0.046) but not for the general population (β = −0.329, p < 0.001).

Conclusions: rs121909567 (SERPINC1, ATBp3) was confirmed as a founder mutation in the Roma population. Our study revealed some evidence on the burden of the joint presence of genetic and environmental risk factors on VTE, although the finding is highly subjected to the selection and observational biases due to the very small number of VTE cases and the observational nature of the study design, respectively. As a result of higher genetic load and GxE interactions, this minority Roma population is at higher risk of VTE than the general Hungarian population. Thus, our results suggest the need for an intensive search for the rs121909567 (SERPINC1; ATBp3) founder mutation, which might be an important factor for the assessment of thrombotic disease susceptibility among the Roma population. In addition, we strongly recommend further studies among a large number of VTE cases to explore the more precise impact of genetic and environmental risk factors on VTE in the study populations.

Anticoagulation for Patients with Venous Thromboembolism: When is Extended Treatment Required?

The need for extended venous thromboembolism (VTE) treatment beyond 3 to 6 months is usually determined by balancing the risk of recurrence if treatment is stopped against the risk of bleeding from continuing treatment. The risk of recurrence, and in turn the decision to extend, can be determined through the nature of the index event. Patients with VTE provoked by surgery or trauma (major transient risk factors) are recommended to receive 3 months of anticoagulation therapy because their risk of recurrence is low, whereas patients with VTE provoked by a major persistent risk factor, such as cancer, or those considered to have “unprovoked” VTE, are recommended to receive an extended duration of therapy based on an established high risk of recurrence. Nonetheless, recent evidence and new guidance identify that this approach fails to consider patients with risk factors classed as minor transient (e.g., impaired mobility and pregnancy) or minor persistent (e.g., inflammatory bowel disease and congestive heart disease). Indeed, the risk of recurrence with respect to VTE provoked by minor persistent risk factors has been demonstrated to be not dissimilar to that of VTE without identifiable risk factors. This review provides an overview of the available data on the risk of recurrence according to the underlying cause of VTE, a critical evaluation of evidence from clinical studies on the available anticoagulants for extended VTE treatment, models of risk prediction for recurrent VTE and bleeding, and guidance on how to apply the evidence in practice.

The utility of thrombophilia and hematologic screening in live liver donation

BACKGROUND

Most centers perform some degree of hematologic screening, including thrombophilia testing, on prospective live liver donors. The nature and extent of such screens are not standardized, and there is limited evidence regarding hematologic risk stratification.

METHODS AND RESULTS

We present an experience of hematologic screening among prospective liver donors. Five-hundred-eightyfour patients were screened for liver donation between 1/2013 and 1/2020, of whom 156 (27%) proceeded to donor hepatectomy. Thirty-three of 428 (8%) declined patients were excluded for hematologic indications. Hematologic indications were the 2nd most frequent medical indications for exclusion (trailing only hepatologic indications). The most common reason for hematologic exclusion was concern regarding thrombophilia. Nevertheless, 21 patients with evidence of possible thrombophilia proceeded to donor hepatectomy, and none incurred hematologic complications. Similarly, seven patients with screening findings concerning for increased bleeding risk (most often thrombocytopenia) underwent donor hepatectomy without hematologic complication. Three of 156 (2%) of patients who underwent donor hepatectomy incurred a hematologic complication (all thrombotic, none fatal). None of these patients had any evident hematologic risk factor on screening.

CONCLUSION

This study underscores the difficulty of hematologic risk stratification among prospective living donors, however, suggests that some patients with relatively mild risk factors may be safe for donation.

Exploring Opportunities for Primary Prevention of Unprovoked Venous Thromboembolism: Ready for Prime Time?

Venous thromboembolism (VTE) is an important vascular disease and public health problem. Prevention of VTE has focused mainly on using thromboprophylaxis to avoid provoked VTE or recurrent VTE, with little attention paid to the possibility of preventing the one third to one half of VTEs that are unprovoked. We review growing research suggesting that unhealthy lifestyle risk factors may cause a considerable proportion of unprovoked VTE. Using epidemiologic data to calculate population attributable risks, we estimate that in the United States obesity may contribute to 30% of VTEs, physical inactivity to 4%, current smoking to 3%, and Western dietary pattern to 11%. We also review possibilities for VTE primary prevention either through a high-risk individual approach or a population-wide approach. Interventions for outpatients at high VTE risk but without VTE provoking factors have not been fully tested; yet, improving patient awareness of risk and symptoms, lifestyle counseling, and possibly statins or direct oral anticoagulants may prove useful in primary prevention of unprovoked VTE. A population approach to prevention would bolster awareness of VTE and aim to shift lifestyle risk factors downward in the whole population using education, environmental changes, and policy. Assuming the epidemiological associations are accurate, causal, and independent of each other, a reduction of obesity, physical inactivity, current smoking, and Western diet by 25% in the general population might reduce the incidence of unprovoked VTE by 12%. We urge further research and consideration that primary prevention of unprovoked VTE may be a worthwhile public health aim.

Identification of Chinese Hospitalized Patients' Risk Profile for Venous Thromboembolism (DissolVE1): A Study Protocol of a Non-Interventional Registry Study

INTRODUCTION

Venous thromboembolism (VTE) is a frequent cause of hospitalization, mortality, and long-term adverse consequence among medical and surgical inpatients. The current study is performed to identify the prophylaxis of patients with VTE risk within the 6 weeks prior to the diagnosis of VTE, and the treatment pattern during 3 months after VTE diagnosis in Chinese patients hospitalized for surgeries or medical illness.

METHODS

This multicenter, non-interventional, observational registry plans to enroll 1200 patients from 40 centers in China. The study will retrospectively collect data from patients' hospitalization record within 6 weeks of VTE diagnosis and prospectively follow-up patients for 3 months (in four visits). The primary outcome is to determine the percentage of patients receiving adequate prophylaxis in patients hospitalized within 6 weeks before VTE diagnosis and treatment pattern within 3 months after VTE diagnosis. Important secondary endpoints include determining patients with risk of VTE in the hospital setting, risk factors for VTE, and cost analysis of VTE treatment.

EXPECTED OUTCOMES

The findings will determine the characteristics of VTE, its treatment practices, cost of treatment, and quality of life in patients; this information may help in building diagnostic and prophylaxis strategies for VTE in China.

TRIAL REGISTRATION

The study is registered in the Venous Thromboembolism Registry in China with study number DIREGL07581.

FUNDING

Sanofi China.

High energy injury is a risk factor for preoperative venous thromboembolism in the patients with hip fractures: A prospective observational study

BACKGROUND

The purpose of this study was to identify the incidence of preoperative venous thromboembolism (VTE), and determine if high energy hip fracture affects preoperative VTE occurrence.

METHODS

Three-hundred nine patients (244 low and 61 high energy injuries) treated between March 2015 and March 2017 were included in this study. Indirect multidetector computed tomographic venography for the detection of preoperative VTE was performed at admission. The incidence of preoperative VTE was compared between high and low energy injury hip fractures. Logistic regression analysis was used to identify independent risk factors for preoperative VTE.

RESULTS

The overall incidence of preoperative VTE was 18.4% (56 of 305 patients). Preoperative VTE was identified in 17 (27.9%) and 39 (16.0%) patients in the high and low energy injury groups, respectively (p = 0.034). Multivariate logistic regression analysis showed that high energy injury, history of VTE, and myeloproliferative disease were significant predictive factors of preoperative VTE (OR = 2.451; 95% CI = 1.227-4.896, OR = 11.174; 95% CI = 3.500-35.673, OR = 6.936; 95% CI = 1.641-29.321, respectively) CONCLUSION: Because high energy hip fracture is significantly associated with preoperative VTE occurrence, preoperative evaluation and proper thromboprophylaxis should be performed for patients with a high-energy hip fracture.

Family history of venous thromboembolism as a risk factor and genetic research tool

Familial clustering of venous thromboembolism (VTE) was described as far back as 1905 by Briggs. Although Egeberg discovered inherited deficiency of antithrombin in 1965, it was not until Dahlback discovered resistance to activated protein C in 1993 that it became clear that genetic factors are common risk factors of VTE. Several genes have been linked to familial aggregation of VTE and genome-wide association studies have found several novel gene loci. Still, it has been estimated that much of the heritability for VTE remains to be discovered. Family history (FH) of VTE is therefore still important to determine whether a patient has an increased genetic risk of VTE. FH has the potential to represent the sum of effects and interactions between environmental and genetic factors. In this article the design, methodology, results, clinical and genetic implications of FH studies of VTE are reviewed. FH in first-degree relatives (siblings and/or parents) is associated with a 2–3 times increased familial relative risk (FRR). However, the FRR is dependent on age, number of affected relatives, and presentation of VTE (provoked/unprovoked). Especially high familial risks are observed in individuals with two or more affected siblings (FFR> 50). However, the familial risk for recurrent VTE is much lower or non-significant. Moreover, FH of VTE appears mainly to be important for venous diseases (i. e. VTE and varicose veins). The familial associations with other diseases are weaker. In conclusion, FH of VTE is an important research tool and a clinically potential useful risk factor for VTE.

F11 is associated with recurrent VTE in women

Genetic associations for the reoccurrence of venous thromboembolism (VTE) are not well described. Our aim was to investigate if common genetic variants, previously found to contribute to the prediction of first time thrombosis in women, were associated with risk of recurrence. The Thromboembolism Hormone Study (TEHS) is a Swedish nationwide case-control study (2002–2009). A cohort of 1,010 women with first time VTE was followed up until a recurrent event, death or November 2011. The genetic variants in F5 rs6025, F2 rs1799963, ABO rs514659, FGG rs2066865, F11 rs2289252, PROC rs1799810 and KNG1 rs710446 were assessed together with clinical variables. Recurrence rate was calculated as the number of events over the accumulated patient-time. Cumulative recurrence was calculated by Kaplan-Meier curve. Cox proportional-hazard model was used to estimate hazard ratios (HR) and 95 % confidence intervals (95 % CI) between groups. A total of 101 recurrent events occurred during a mean follow-up time of five years. The overall recurrence rate was 20 per 1,000 person-years (95 % CI; 16-24). The recurrence rate was highest in women with unprovoked first event and obesity. Carriers of the risk alleles of F5 rs6025 (HR=1.7 (95 % CI; 1.1–2.6)) and F11 rs2289252 (HR=1.8 (95 % CI; 1.1–3.0)) had significantly higher rates of recurrence compared to non-carriers. The cumulative recurrence was 2.5-fold larger in carriers of both F5 rs6025 and F11 rs2289252 than in non-carriers at five years follow-up. In conclusion, F5 rs6025 and F11 rs2289252 contributed to the risk of recurrent VTE and the combination is of potential clinical relevance for risk prediction.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Family history of venous thromboembolism and mortality after venous thromboembolism: a Swedish population-based cohort study

Studies on whether family history (FH) of venous thromboembolism (VTE) affects long-term mortality after VTE are missing. The aim of this study was to determine whether FH of VTE affects long-term mortality after a first episode of VTE. Using Swedish medical databases, we conducted a 30-year nationwide cohort study of 49,159 adult Swedish born patients included in the multi-generation register (born 1932 or later) with a first-time VTE (1981–2010). Using Cox regression, we assessed mortality Hazard ratios (HRs) with 95% confidence intervals (CIs). Totally 10,093 (20.5%) patients with VTE had a first-degree FH of VTE (parent/sibling). Patients without FH of VTE had significantly more VTE provoking risk factors and comorbidities than those with FH. The mortality HR the first 10-years after first time VTE was decreased for those with FH of VTE compared to for those without FH: crude HR 0.807, 95% CI 0.771–0.845 and adjusted HR 0.864, 95% CI 0.826–0.905. After 10-years of follow-up there was no significant effect of FH of VTE on mortality: crude HR = 1.018, 95% CI 0.905–1.145 and adjusted HR = 0.995, 95% CI 0.884–1.119. Cancer-associated mortality was more common in those without FH the first 10 years (56.9 vs. 53.4%, p = 0.002). After 10 years there were no difference in cancer-associated mortality (4.9 vs. 5.6%, p = 0.604). The results suggest that patients with FH of VTE have lower thrombotic threshold and need less provoking factors and comorbidities. They have also slightly lower total and cancer mortality the first 10 years after VTE.

Risk factors for symptomatic venous and arterial thromboembolism in newborns, children and adolescents - What did we learn within the last 20years?

Venous thrombosis (VTE) in children is increasingly diagnosed, as advanced medical care has increased treatment intensity of hospitalized pediatric patients. The aim of this review was to summarize the data available and to discuss the controversial issue of thrombophilia screening in the light of the pediatric data available. Follow-up data for VTE recurrence in children suggest a recurrence rate between 3% (neonates) and 21% in individuals with unprovoked VTE. Apart from underlying medical conditions, recently reported systematic reviews on pediatric VTE (70% provoked) have shown significant associations between thrombosis and presence of protein C-, protein S- and antithrombin deficiency, factor 5 (F5: rs6025), factor 2 (F2: rs1799963), even more pronounced when combined inherited thrombophilias [IT] were involved. The F2 mutation, protein C-, protein S-, and antithrombin deficiency did also play a significant role at VTE recurrence. Although we have learned more about the pathophysiology of VTE with the increased discovery of IT evidence is still lacking as to whether IT influence the clinical outcome in pediatric VTE. It still remains controversial as to whether children with VTE or offspring from thrombosis-prone families benefit from IT screening. Thus, IT testing in children should be individualized.

Impact of high risk thrombophilia status on recurrence among children and adults with VTE: An observational multicenter cohort study

BACKGROUND

Antithrombin [AT]-, protein C [PC]- or protein S [PS]-deficiency [D] constitutes a major risk factor for venous thromboembolism [VTE]. Primary study objective was to evaluate if the clinical presentation at first VTE onset differs between children and adults and to compare the individual recurrence risk among patients with respect to age at onset and their thrombophilia status ATD, PCD or PSD.

METHODS/PATIENTS/RESULTS

In 137 of 688 consecutively enrolled pediatric and adult VTE patients we calculated the absolute risk of VTE recurrence and event-free-survival adjusted for thrombophilia and positive family VTE history. At first VTE children manifested i) with a lower rate of pulmonary embolism, ii) a higher rate of cerebral vascular events or multiple VTEs, and iii) showed a higher proportion of unprovoked VTE compared to adolescents and adults. Adult patients reported more often a positive VTE history compared to younger study participants. The adjusted odds of recurrence in adults was 2.05 compared to children.

CONCLUSION

At disease manifestation children and adults differ with respect to i) thrombotic locations, ii) percentage of unprovoked versus provoked VTE, and iii) different rates of positive VTE family histories. Furthermore, adults showed a two-fold increase risk of VTE recurrence compared to children.