Idiopathic Pulmonary Embolism Research Articles

SARS-CoV-2 antibody research in patients with unprovoked pulmonary embolism in COVID-19 pandemic period.

ObjectiveDue to the coronavirus disease 2019 (COVID-19) pandemic, a significant increase has been observed in patients diagnosed with pulmonary embolism (PE) in our clinic. In addition to COVID-19-related PE, the increase in the number of patients with unprovoked or idiopathic PE was also noteworthy. Although it is not surprising that PE due to immobilization was observed in elderly patients and patients with comorbidities at risk for PE during the pandemic, it is important to investigate the increase in the number of unprovoked PE. Thus, we aimed to show that a previous COVID-19 infection may be a risk factor in these patients by examining the presence of severe acute respiratory syndrome-causing coronavirus (SARS-CoV-2) antibodies in patients diagnosed with unprovoked PE.Materials and methodsThe participants of the study consisted of 45 consecutive patients who were diagnosed with PE in our clinic, had no risk factors for PE, were considered unprovoked (idiopathic) PE, and had no history of COVID-19. SARS-CoV-2 antibody titers were measured in the serum samples of the patients for detecting immunity as a result of encountering COVID-19.ResultsOf the 45 patients diagnosed with PE, 24 (53.3%) patients were diagnosed with computed tomography pulmonary angiogram (CTPA), and 21 (46.7%) patients were diagnosed with perfusion single-photon emission computed tomography (Q-SPECT/CT). Immunity acquired after encountering COVID-19 was checked with the NCP kit, which revealed positive results in 9 (20%) patients.ConclusionIt should be kept in mind that some of the patients diagnosed with idiopathic PE during the pandemic may have embolism due to asymptomatic COVID-19. In addition, it is now known that COVID-19 also creates a tendency toward thrombosis in asymptomatic patients.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11239-022-02703-8.

Combination of Acute Exacerbation of Idiopathic Nonspecific Interstitial Pneumonia and Pulmonary Embolism after Booster Anti-COVID-19 Vaccination

Combination of Acute Exacerbation of Idiopathic Nonspecific Interstitial Pneumonia and Pulmonary Embolism after Booster Anti-COVID-19 Vaccination

A significant decrease in D-dimer concentration within one month of anticoagulation therapy as a predictor of both complete recanalization and risk of recurrence after initial pulmonary embolism

BackgroundAbnormal D-dimer concentration measured during anticoagulation therapy (AT) or within one month of discontinuation, is associated with residual pulmonary obstruction (RPO) and risk of recurrent venous thromboembolism (VTE) after a first episode of pulmonary embolism (PE). We hypothesized that a significant decrease in D-dimer concentration within the first month of AT in patients with a first episode of PE may predict complete recanalization and a lower risk of recurrent VTE. MethodsOne hundred and fifty patients with PE received anticoagulation therapy for three or six months when control computed tomography angiography (CTA) was performed. D-dimer levels were measured at admission and at 1-, 3- and/or 6-month follow-ups after the initial event. Clinical, echocardiographic, CTA and analytical data were collected. Predictive factors of RPO and predictive ability of D-dimer concentration at 1- and 6-month follow-ups were evaluated. ResultsOf the 150 eligible patients, 33 (22%) had RPO in control CTA. Idiopathic PE, a delay of >7 days between symptom onset and diagnosis, and clinical PE severity determined by a s-PESI score ≥ 1 were associated with RPO. D-dimer concentration within a month of AT was significantly higher (823 [558–1259] vs 436 [243–934] ng/ml; p = 0.019) in patients with RPO; decrease (445 [35–1899] vs 912 [476–2858] ng/ml; p = 0.047) and decrease percentage (31.4% vs 76.6%; p < 0.005) in D-dimer concentrations were significantly lower. ROC analysis showed that decrease percentage in D-dimer concentration identified patients with complete recanalization (AUC 0.715, [95% CI, 0.611–0.819], p < 0.005). Decreases of >70% in initial D-dimer at 1-month (OR, 0.56, [95% CI, 0.45–0.70] p = 0.037) and 6-month follow-ups (OR, 0.31 [CI 95%, 0.15–0.66], p = 0.03) were associated with a lower risk of recurrent PE. ConclusionA significant decrease in D-dimer concentration within the first month of AT is associated with complete recanalization and could predict a lower risk of recurrent thrombosis after a first episode of PE.

Acute Pulmonary Embolism Mimicking Covid-19 Pneumonia

We report the case of a 21 years old male patient, with a history of asthma since the age of 8 months, without follow-up, presenting a severe respiratory distress appeared suddenly, associated with a right basithoracic pain, and moderate hemoptysis. The non-contrast CT-chest scan showed a basal ground-glass opacity of the right lung leading to suspicion of Covid 19s’ pneumonia. Laboratory tests reveal an elevated levels of D-dimers (D-D), a thrombocytopenia, a neutrophilic leukocytosis and a hyper eosinophilia. The molecular test RT-PCR is negative. With the persistence of the right-side basithoracic pain and the presence of a hyper eosinophilia and increased levels of D-Dimers. A thoracic CT angiography was indicated that shows a bilateral distal pulmonary embolism with a right-sided basal sub segmental ischemia. We discuss a fortuitous discovery of an idiopathic pulmonary embolism associated to peripheral basal ground-glass opacities similar to the radiological findings found in the case of a SARS-Cov-2 pneumonia.

Influence of weather and air pollution on the occurrence of idiopathic pulmonary embolism in the region of Sousse (Tunisia).

Pulmonary embolism (PE) is the most serious manifestation of thromboembolic conditions. Its incidence varies considerably between countries, suggesting its interaction with the external environment. To analyze the influence of climate and air pollution on the occurrence of idiopathic PE in the region of Sousse (Tunisia). A total of 142 patients with idiopathic PE at two academic hospitals in Sousse (Tunisia) were enrolled in the study over a 7-year period. An analysis of two time series (environmental data and PE cases) was performed. Climatic data were collected from the National Institute of Meteorology. Air pollution data were obtained from the modeling platform of the National Agency for Protection of the Environment. The year 2015 was marked by the occurrence of the highest number of cases (24.6%). A statistically significant decrease in PE risk of 41.9% was observed during the summer with an OR of 0.59 (95% CI [0.36-0.94] and p = 0.026), compared with other seasons. Poisson GLM regression showed a significant increased risk of PE of 3.3% for each 1°C temperature drop. After multiple binary logistic regression, the elevation of PM10 concentration was independently associated with an increased risk of PE (p < 10-3, OR 79.55, 95% CI [42.28-149.6]). Some environmental parameters may predispose to the onset of idiopathic PE. Understanding their accurate influence may have preventive and curative implications.

Long term prognosis of acute pulmonary embolism

BackgroundAcute pulmonary embolism (PE) can be fatal if left untreated. Long-term prognosis of acute PE in the 21st century has not been fully reported. We aimed to determine the long-term prognosis of patients hospitalized with acute PE and compare survivalof patients with idiopathic and secondary PE. Materials and methodsWe retrospectively analysed a cohort of hospitalized patients with acute PE between 2006 and 2013. Exclusion criteria:<18 years, venous embolism of non-pulmonary veins, chronic thromboembolic pulmonary hypertension, and presumptive diagnosis without image confirmation. Only patients with a first PE episode were included. End-point: all-cause mortality. Patients were compared according to PE aetiology: idiopathic, secondary to neoplastic conditions and secondary to non-neoplastic conditions. A Cox-regression analysis was used to study the prognostic impact of PE aetiology. RESULTS: We studied 872 hospitalized acute PE patients. Median age 70 years, 56.9% were women. PE was idiopathic in 376 (43.1%), secondary to a neoplastic condition in 284 (32.6%) and secondary to a condition other than neoplasia in 212 (24.3%). Patients were followed for a median 25 months period and 508 (58.3%) died. Patients with PE attributed to a neoplastic condition had the worst survival. Patients with idiopathic PE had a multivariate-adjusted HR of mortality of 1.46 (1.08–1.99) during the over 2-year follow-up period when compared to those with acute PE attributed to a non-neoplastic condition. ConclusionsPatients with idiopathic acute PE have an almost 50% higher death risk in a median 2-year follow-up period than those with acute PE secondary to a condition other than neoplasia.

Alcohol consumption and the risk of incident pulmonary embolism in US women and men

Background Moderate alcohol consumption has been variably associated with hemostatic and fibrinolytic factor levels, but the association between alcohol consumption and the risk of incident pulmonary embolism (PE) remains uncertain. Objective To evaluate alcohol consumption amount and frequency in relation to PE risk. Methods Nurses' Health Study (NHS), NHS II and Health Professionals Follow-Up Study participants free of venous thromboembolism (VTE) at baseline (n = 217 442) reported alcohol consumption by type, quantity and frequency, every 2-4 years. Incident PE cases were identified by self-report and confirmed for participants without cancer. In this cohort study, we used Cox proportional hazards models to estimate multivariable-adjusted hazard ratios (HRs) for PE associated with alcohol consumption amount and, separately, frequency. Secondary analyses evaluated alcohol type and heavy episodic drinking in relation to PE risk, and amount and frequency in relation to medical record-confirmed idiopathic PE and any self-reported VTE risk. Cohort-specific analyses were pooled using random-effects meta-analysis. Results During ≥ 20 years of follow-up, we identified 1939 PE events. We found no strong evidence of an association between PE risk and alcohol consumption amount (pooled HRadj for 5.0-14.9 g day-1 vs. abstention = 0.97 [95% CI, 0.79, 1.20]) or frequency (pooled HRadj for 5-7 drinking days per week vs. abstention = 1.04 [95% CI, 0.88, 1.23]). Secondary analyses of type, heavy episodic drinking, idiopathic PE and VTE also yielded null findings. Conclusions Among three large prospective cohorts of US men and women, we found no evidence of an association between the amount or frequency of alcohol consumption and PE risk.

Incidence and risk factors of chronic thromboembolic pulmonary hypertension after acute pulmonary embolism: a systematic review and meta-analysis of cohort studies.

The incidence and risk factors of chronic thromboembolic pulmonary hypertension (CTEPH) after acute pulmonary embolism (PE) were still controversial. A systematic review and meta-analysis was conducted to assess the incidence and risk factors of CTEPH after acute PE. Embase, Medline, China National Knowledge Infrastructure, Wanfang databases, and various reference lists were searched to identify studies published up to May 2018. Only cohort studies that used right heart catheterization for CTEPH diagnosis were included. The study quality was assessed using the Newcastle-Ottawa Scale (NOS). All analyses were conducted with the meta package in R software (3.2.2). Fifteen studies met the inclusion criteria. The overall incidence of CTEPH after acute PE, with a median follow-up from 6 to 94.3 months, was 3.13% (95% CI: 2.11-4.63%). The incidence of studies from China [4.46% (95% CI: 1.68-11.32%)] was slightly higher than from Europe [2.82% (95% CI: 1.82-4.34%)]. However, there was no significant difference between these two groups (P=0.39). Subgroup analyses of confirmed diagnostic method showed that compared studies using right heart catheterization [3.25% (95% CI: 2.12-4.97%)], studies using right heart catheterization combined with bundled tests tended to yield a similar data [2.40% (95% CI: 0.97-5.81%), P=0.54]. Previous/recurrent PE or previous VTE, idiopathic PE and right heart dysfunction were considered as risk factors of CTEPH in patients with a previous PE. CTEPH is not a rare complication of acute PE. Close follow-up and implementation of a comprehensive screening program are important, especially in patients with independent risk factors.

Abstract P272: Dietary Intake of Vitamin K and the Risk of Incident Pulmonary Embolism in the Nurses’ Health Study

Introduction: Vitamin K, which is consumed as phylloquinone (K 1 ) and menaquinone (K 2 ), impacts some vitamin-K dependent proteins involved in hemostasis. It is unknown whether dietary intake of phylloquinone and menaquinone are associated with incident pulmonary embolism (PE) risk. Hypotheses: Dietary intake of phylloquinone and menaquinone will be positively associated with the risk of incident PE and, in secondary analyses, idiopathic PE. Methods: Eligible women were Nurses’ Health Study participants free of venous thromboembolism (VTE) at 1984 baseline (n=74,821). Participants completed a food frequency questionnaire every four years (1984-2010) and we calculated intake of phylloquinone and menaquinone. Eligible PE cases were confirmed via medical record review or participant reconfirmation, or self-reported among persons with prior cancer. Cases were defined as idiopathic in the absence of cancer, recent surgery, and trauma. Cox Proportional Hazards models estimated hazard ratios and 95% confidence intervals for PE associated with time-varying energy-adjusted quintiles of phylloquinone, and separately, menaquinone. Two models adjusted for time-varying covariates, first including lifestyle and medical factors and next adding energy-adjusted nutrients. Secondary analyses estimated idiopathic PE risk. Results: We identified 568 incident PE events during 1,328,669 person-years. In analyses adjusted for lifestyle and medical factors, there was no evidence of a linear association between incident PE risk and energy-adjusted quintiles of phylloquinone intake (linear p-trend across quintile medians = 0.37) or menaquinone intake (linear p-trend = 0.57). Results for idiopathic PE risk were similarly null, as were results after further adjustment for nutrients (Table). Conclusions: In this study of U.S. women, there was no evidence of a linear association between energy-adjusted quintiles of phylloquinone or menaquinone intake and incident PE risk, before or after adjustment for other nutrients.

Factors Associated with Pulmonary Embolism Recurrence and the Benefits of Long-term Anticoagulant Therapy.

Venous thromboemboli tend to recur. However, the causative factors underlying pulmonary embolism recurrence are not well defined. To explore the factors associated with pulmonary embolism recurrence. Patients diagnosed with pulmonary emboli between 2004 and 2013 at our institution were enrolled. Duration of anticoagulant therapy, new episodes of venous thromboembolism, and deaths were recorded. Pulmonary embolism was diagnosed in 528 patients (median age: 76 years, interquartile range [IQR]: 16; male: 45%). The median follow-up time was 34 months (IQR: 52). In total, 477 patients completed ≥3 months of anticoagulation therapy. Permanent anticoagulation was indicated in 217 (45%) patients, and therapy was discontinued in 260 (55%) patients. Overall, 79 patients experienced a recurrence (5.6 per patient-year). Recurrence was significantly associated with anticoagulation discontinuation (4% vs. 27% of patients who maintained or discontinued therapy, respectively; P<0.001; 95% confidence interval -0.95, -0.86). The median duration between anticoagulation withdrawal and recurrence was 6.5 months (IQR: 23.25). Factors associated with recurrence were unprovoked pulmonary embolism (odds ratio [OR]: 0.45), a greater degree of pulmonary arterial obstruction (OR: 2.5), a delay in initiation of anticoagulation (OR: 3), and higher plasma D-dimer levels during treatment (OR: 2.3). Survival rates were improved for patients who maintained anticoagulation therapy relative to those who discontinued. Pulmonary embolism has a high recurrence rate. Permanent anticoagulant therapy should be considered for patients with idiopathic pulmonary embolism, a high thrombotic burden, and persistently elevated D-dimer levels during treatment, and for patients where therapy was initially delayed.

Evaluation of incidence of chronic thromboembolic pulmonary hypertension after acute pulmonary embolism in patients admitted to Imam Reza Hospital, Tabriz, Iran (primary results)

Introduction: Chronic thromboembolic pulmonary hypertension (CTEPH) is a late complication of pulmonary thromboembolism, which is associated with high morbidity and mortality. Although the pathogenesis is not fully understood, the damage and frequency of this complication have a wide range. The aim of this study was to evaluate the incidence of CTEPH following the first episode of acute pulmonary embolism (PE). Methods: In a cohort study, 101 patients with acute embolism who had undergone anticoagulant therapy were followed up for at least one year. Patients that presented symptoms of dyspnea were selected. Echocardiography was performed on these patients, and they were evaluated for symptoms of right heart failure and increased pulmonary artery pressure of more than 35 mmHg. Results: 101 patients with a mean age of 85.2 ± 17.7 years, including 57 men (56.4%) and 44 females (43.6%), were treated for a diagnosis of acute PE and were followed up for one year. 77.2% of patients had an idiopathic PE and 22.8% had it as the underlying cause. During follow-up, 23 patients (22.8%) experienced dyspnea. Echocardiography was normal in 13 cases and 10 cases had signs of right heart failure and pulmonary artery pressure. The overall incidence of CTEPH was 9.9%. Demographic data and computed tomography (CT) angiography findings were not associated with higher incidence of CTEPH. Conclusion: CTEPH is a serious complication of acute PE, and the incidence of pulmonary hypertension after pulmonary emboli is relatively high. Age and gender did not influence its occurrence. Moreover, there was no relationship between the findings of CT angiography in the initial PE and chronic pulmonary hypertension rate of incidence.

Venous thromboembolism — recommendations on the prevention, diagnostic approach and management. The 2017 Polish Consensus Statement

The 2017 Polish Consensus Statement (PCS 2017) includes updated recommendations on the prevention, diagnostic approach, and management of venous thromboembolism (VTE). For VTE without cancer, the authors of PCS 2017 recommend apixaban, edoxaban, rivaroxaban, and dabigatran over vitamin K antagonists (VKA) as long-term anticoagulant therapy. For VTE with cancer, the authors of PCS 2017 recommend low molecular weight heparins (LMWH) over VKA, apixaban, edoxaban, rivaroxaban and dabigatran. For extended secondary prevention of deep venous thrombosis (DVT), PCS 2017 recommends apixaban, edoxaban, rivaroxaban, dabigatran, VKA, and sulodexide. For extended secondary prevention of pulmonary embolism (PE), PCS 2017 recommends apixaban, edoxaban, rivaroxaban, dabigatran and VKA. For extended secondary prevention in patients with idiopathic DVT and a high risk of bleeding complications, the authors of PCS 2017 recommend NOT to stop anticoagulation and use sulodexide. For extended secondary prevention in patients with idiopathic PE and a high risk of bleeding, the authors of PCS 2017 recommend NOT to stop anticoagulation and suggest treatment with apixaban, edoxaban, rivaroxaban, and dabigatran in reduced doses adjusted to the risk of bleeding. For VTE treated with anticoagulants, PCS 2017 recommends against insertion of a vena cava filter. For patients with DVT, PCS 2017 suggests USING compression stockings routinely to prevent postthrombotic syndrome. For subsegmental PE without proximal DVT, PCS 2017 suggests clinical surveillance over anticoagulation with a low risk of recurrent VTE, and anticoagulation over clinical surveillance with a high risk of recurrent VTE. The 2017 Polish Consensus Statement suggests thrombolytic therapy for PE with hypotension, and systemic therapy over catheter-directed thrombolysis. For recurrent VTE on a non-LMWH anticoagulant, PCS 2017 suggests LMWH, and for recurrent DVT and/or PE on LMWH, PCS 2017 suggests increasing the dose of LMWH.

Abstract P245: Amount and Frequency of Alcohol Consumption and the Risk of Incident Pulmonary Embolism in the Nurses’ Health Study

Introduction: Moderate alcohol consumption has been associated with differences in hemostatic factor levels that may lead to a lower thrombotic risk, but the association between alcohol consumption and the risk of incident pulmonary embolism (PE) has been inconsistent. Hypotheses: Moderate alcohol consumption is associated with a lower PE risk than lower or higher quantities, and more frequent alcohol consumption is associated with a lower PE risk than less frequent alcohol consumption. Methods: Nurses’ Health Study participants free of venous thromboembolism in 1984 (n=79,914) reported alcohol consumption every two-four years between 1984 and 2012 and number of drinking days per week on five questionnaires between 1986 and 2004. PE were initially identified by self-report and were confirmed for the subset of patients without a previous cancer using a combination of medical record review and participant reconfirmation. Cox Proportional Hazards models estimated multivariable-adjusted hazard ratios for PE associated with average amount of alcohol consumed and, separately, drinking days per week. Secondary analyses estimated the risk of medical-record confirmed idiopathic PE, events which were not associated with surgery, trauma, or cancer. Results: We identified 1,112 total incident PE events, including 360 idiopathic PE events, during 28 years of follow-up. In multivariable-adjusted analyses, we found no strong evidence of an association between the amount of alcohol consumed per day and the risk of any PE (quadratic p-trend=0.3) or idiopathic PE (quadratic p-trend=0.4) or between the frequency of alcohol consumption and the risk of any PE (linear p-trend=0.5) or idiopathic PE (linear p-trend=0.8) (Table). Conclusions: Among this population of women with relatively low average amounts of alcohol consumption, we found no substantial evidence of an association between the amount or frequency of alcohol consumption and the risk of PE.

Severe Thrombophilia in Idiopathic Fatal Pulmonary Embolism

Severe Thrombophilia in Idiopathic Fatal Pulmonary Embolism

Whole Exome Sequencing Reveals Severe Thrombophilia in Acute Unprovoked Idiopathic Fatal Pulmonary Embolism

BackgroundAcute unprovoked idiopathic fatal pulmonary embolism (IFPE) causes sudden death without an identifiable thrombogenic risk. We aimed to investigate the underlying genomic risks of IFPE through whole exome sequencing (WES). MethodsWe reviewed 14years of consecutive out-of-hospital fatal pulmonary embolism records (n=1478) from the ethnically diverse population of New York City. We selected 68 qualifying IFPE cases for WES. We compared the WES data of IFPE cases to those of 9332 controls to determine if there is an excess of rare damaging variants in the genome using ethnicity-matched controls in collapsing analyses. FindingsWe found nine of the 68 decedents (13·2%) who died of IFPE had at least one pathogenic or likely pathogenic variant in one of the three anti-coagulant genes: SERPINC1 (Antithrombin III), PROC, and PROS1. The odds ratio of developing IFPE as a variant carrier for SERPINC1 is 144·2 (95% CI, 26·3–779·4; P=1·7×10−7), for PROC is 85·6 (95% CI, 13·0–448·9; P=2.0×10−5), and for PROS1 is 56·4 (95% CI, 5·3–351·1; P=0·001). The average age-at-death of anti-coagulant gene variant carriers is significantly younger than that of non-carriers (28·56years versus 38·02years; P=0·01). InterpretationThis study showed the important role of severe thrombophilia due to natural anti-coagulant deficiency in IFPE. Evaluating severe thrombophilia in out-of-hospital fatal PE beyond IFPE is warranted.

Clinical Prognosis of Nonmassive Central and Noncentral Pulmonary Embolism: A Registry-Based Cohort Study

Whether the localization of nonmassive pulmonary embolism (PE) is associated with the short-term and long-term prognosis of patients remains unknown. Our aim was to characterize associations of nonmassive PE localization with risks of recurrent VTE, major bleeding, and mortality during and after anticoagulation. Among participants of the Registro Informatizado de la Enfermedad ThromboEmbòlica (RIETE) registry with incident symptomatic nonmassive PE diagnosed by CT scan, we compared risks of recurrent VTE, major bleeding, and mortality during and after anticoagulation between central PE (main pulmonary artery) and noncentral PE (more peripheral arteries) using Cox proportional hazard-adjusted models. Of the 6,674 participants, patients with central PE (40.5%) had age (mean 66 years), sex (46.9%male sex), and proportion of idiopathic (45.0%) and cancer-related (22.3%) PE that were similar to those of patients with noncentral PE. During anticoagulation (5,256.1 patient-years), the risk of recurrent VTE was similar between the two groups (2.5 vs2.1 per 100 patient-years; adjusted hazard ratio [aHR], 1.32; 95%CI, 0.91-1.90), as were risks of major bleeding and mortality. After anticoagulation was discontinued (2,175.4 patient-years), participants with central PE had a borderline greater risk of recurrent VTE than did participants with noncentral PE (11.0 vs8.0 per 100 patient-years; aHR, 1.34; 95%CI, 1.01-1.78) but not when restricted to participants after unprovoked PE (13.8 vs11.9 per 100 patient-years; aHR, 1.15; 95%CI, 0.79-1.68; P= .48). Risks of major bleeding and mortality were similar. In nonmassive PE, central localization of PE is associated with greater risk of recurrent VTE after anticoagulation cessation. However, the low magnitude of this association and the absence of association after unprovoked PE suggest that the clinical relevance of this finding is limited and that the duration of anticoagulation should not be tailored to PE localization after nonmassive unprovoked PE.

Venous thromboembolism has the same risk factors as atherosclerosis: A PRISMA-compliant systemic review and meta-analysis.

Previous studies have shown that idiopathic pulmonary embolism is positively associated with other cardiovascular events, such as myocardial infarction and stroke, suggesting a potentially important association between atherosclerosis risk factors and venous thromboembolism (VTE). We performed a meta-analysis to evaluate the correlation between risk factors for atherosclerosis and VTE. In December 2014, we searched MEDLINE and EMBASE for studies evaluating the associations between VTE and risk factors for atherosclerosis and pooled outcome data using random-effects meta-analysis. In addition, we analyzed publication bias. Thirty-three case-control and cohort studies with a total of 185,124 patients met the inclusion criteria. We found that participants with body mass index (BMI) ≥30 kg/m had a significantly higher prevalence of VTE than those with BMI <30 kg/m in both case-control studies (odds ratio [OR] = 2.45, 95% confidence interval [CI]: 1.78-3.35) and cohort studies (relative risk [RR] = 2.39, 95% CI: 1.79-3.17). VTE was more prevalent in patients with hypertension than without hypertension (OR = 1.40, 95% CI: 1.06-1.84; RR = 1.36, 95% CI: 1.11-1.67). The findings were similar for VTE prevalence between patients with and without diabetes (OR = 1.78, 95% CI: 1.17-2.69; RR = 1.41, 95% CI: 1.20-1.66). Current smoking was significantly associated with VTE prevalence in case-control studies (OR = 1.34, 95% CI: 1.01-1.77), but not in cohort studies (RR = 1.29, 95% CI: 0.96-1.72). In addition, we found that total cholesterol and triglyceride concentrations were significantly higher in patients with VTE than without VTE (weighted mean differences [WMD] = 8.94 mg/dL, 95% CI: 3.52-14.35 mg/dL, and WMD = 14.00 mg/dL, 95% CI: 8.85-19.16 mg/dL, respectively). High-density lipoprotein cholesterol concentrations were significantly lower in patients with VTE than without VTE (WMD = -2.03 mg/dL, 95% CI: -3.42 to -0.63 mg/dL). Higher quality studies were more homogeneous, but confirmed the same significant associations. Based on our systematic review and meta-analysis, we observed a significant association between VTE and the risk factors for atherosclerosis. These results may make an important contribution to clinical practice regarding VTE treatment.

Elevated factor VIII activity and venous thromboembolism in patients referred to the Iranian Blood Transfusion Organization: A case control study

ObjectiveA high plasma level of factor eight (FVIII) is a risk factor for venous thromboembolism (VTE). Since, there was no report about the association of elevated FVIII and VTE in Iranian population, the incidence of elevated FVIII and its association to VTE was evaluated. Materials and methods152 consecutive idiopathic VTE patients referred to the Iranian Blood Transfusion Organization (IBTO) and 130 healthy matched blood donors were studied. At least one confirmed idiopathic deep vein thrombosis (DVT) or pulmonary embolism (PE) was found among all cases. The blood samples were collected at least 3 months after DVT/PE diagnosis. The normal reference range was determined by using the Control samples of the donors. FVIII levels were measured using PTT based one-staged assay. ResultsThe FVIII levels in the cases and controls were 157.3±53.4 and 111.8±29.7, respectively. In cases, the lowest and the highest levels of FVIII were 66IU/dl and 364IU/dl, while they were 42IU/dl and 195IU/dl for the controls.There was no relation between gender, age and FVIII level in either group. The normal reference range for the controls was 52–171IU/dl. Considering the cut-off point as 180IU/dl, the elevated values were seen in 28.9% of the case group vs. 3.1% of the control group. ConclusionElevated factor VIII is likely to be a risk factor for VTE. Moreover, a new normal reference range for the Iranian population was defined.

Utility and prevalence of imaging for underlying cancer in unprovoked pulmonary embolism.

Current guidelines state that patients over 40 years of age with a first unprovoked pulmonary embolism should be offered limited screening for possible cancer and considered for intensive screening (abdomino-pelvic computed tomography and mammography), despite no evidence for the latter. The aim of this study was to evaluate the clinical utility and cost of intensive screening in routine clinical practice. Methods All patients diagnosed with a first unprovoked pulmonary embolism between January 2014 and June 2014 in a single large UK teaching hospital were included. The information management department searched for patients with an International Classification of Diseases 10 discharge diagnosis of pulmonary embolism and limited to 'acute pulmonary embolism with/without cor pulmonale'. Only patients with unprovoked pulmonary embolism were included. Patients with chronic medical conditions predisposing to pulmonary embolism were excluded. NHS costs were obtained from the Trust Finance Department. These costs were used to generate the costs of limited versus intensive screening, and then scaled up using adult population census information and assuming the same incidence of idiopathic pulmonary embolism to estimate the annual NHS cost of intensive screening. Results Ninety-two patients were diagnosed with pulmonary embolism, and 25 met the inclusion criteria. Clinical examination was often incomplete (84%). Limited screening was often missed (urinalysis 100%, serum calcium 64%). Intensive screening was performed in the majority of cases (68%, all abdomino-pelvic computed tomography with no cancer detected) with an £88 excess cost per patient. Conclusion Intensive screening in first unprovoked pulmonary embolism has a low yield, is costly and should not replace thorough clinical examination and basic screening.

Are Meteorological Parameters a Risk Factor for Pulmonary Embolism? A Retrospective Analysis of 530 Patients.

The influence of meteorological conditions on cardiovascular morbidity and mortality has been known for a long time. However, few reports have been published on the influence of meteorological parameters on the occurrence of acute pulmonary embolism (PE). In this retrospective study, we compared the meteorological parameters between PE patients with risk factors and idiopathic PE patients. Cross-sectional study. Medical documentation of 1180 patients with suspected acute pulmonary embolism diagnosed between January 2010 and December 2012 was retrospectively analyzed. A total of 530 patients with PE confirmed by computed tomography pulmonary angiography and/or ventilation/perfusion scan were included for further analysis. We divided the patients into two groups: PE with risk factors (provoked) and PE without risk factors (unprovoked). The meteorological data were collected from the relevant time period: temperature, humidity, pressure, and wind velocity. As the exact time of PE onset was unknown, the meteorological values attributed to each patient were the means of the values in the months or weeks at the time of diagnosis of PE. The highest numbers of cases were seen in autumn (29.8%), followed by summer (28.9%), spring (22.1%), and winter (19.2%). In terms of months, the greatest number of cases occurred in June (57), followed by November (56) and October (54). Case distribution according to the months and seasons were statistically significant. The wind direction also affected the incidence of PE. There was a statistically significant positive correlation between case frequency and air temperature (r=0.300; p=0.031). No correlation was found between the unprovoked PE cases' monthly distribution and pressure, humidity, or temperature. However, there was a statistically significant positive correlation between the monthly distribution of the group with provoked PE cases and air temperature (r=0.586; p=0.045). A statistically significant inverse correlation between atmospheric pressure and temperature and the number of all PE cases was observed in our study, which is in accordance with other reports. However, in unprovoked PE cases, there was no correlation between meteorological parameters and case incidence.