COPD and risk of venous thromboembolism and mortality in a general population

Venous thromboembolism in patients hospitalized for hip joint replacement surgery

BACKGROUND

Venous thromboembolism (VTE) is a potentially life-threatening disease. Major transient risk factors include trauma, surgery, and immobilization. Patients undergoing hip joint replacement (HJR) are characterized by a high risk of postoperative VTE, but data on the time trends of VTE rates in this population are sparse.

METHODS

In an analysis of the German nationwide inpatient sample, we included all hospitalizations for elective primary HJR in Germany from 2005 to 2016. Time trends of the surgical procedure, overall death rates, and VTE rates were analysed, and predictors of VTE identified.

RESULTS

Overall, 1,885,839 inpatients with elective primary HJR (59.1% women, 51.4% ≥70 years) were included in the analysis. During hospitalization, VTE was documented in 11,554 (0.6%) patients. While total numbers of primary HJR increased from 145,223 in 2005 to 171,421 in 2016 (β-(slope)-estimate 1818 [95%CI 1083 to 2553], P < 0.001), in-hospital VTE decreased from 1288 (0.9%) to 843 (0.5%) cases (β-estimate -0.71 [95%CI -0.77 to -0.65], P < 0.001), and in-hospital death rate from 0.33% (476 deaths) to 0.29% (498 deaths) (β-estimate -0.11 [95%CI -0.20 to -0.02], P = 0.018). Infections during hospitalization were associated with higher VTE risk than cancer and cardiovascular events. VTE events were independently associated with an increased death risk (OR 15.19 [95%CI 14.19-16.86], P < 0.001).

CONCLUSIONS

While total numbers of HJR increased significantly in Germany between 2005 and 2016, in-hospital rates of VTE decreased from 0.9% to 0.5%. Patients with perioperative VTE had a 15-fold increase of in-hospital death. Cancer, cardiovascular disease and perioperative infections were associated with higher risk for VTE.

Isolated Pulmonary Embolism Is Associated With a High Risk of Arterial Thrombotic Disease: Results From the VTEval Study

BACKGROUND

Isolated PE is associated with a higher burden of atherosclerotic disease than other manifestations of VTE.

RESEARCH QUESTION

We hypothesized that the presence of isolated PE may signal a chronically elevated risk of arterial thrombotic disease.

STUDY DESIGN AND METHODS

Data from the VTEval Study, a prospective cohort study enrolling individuals with clinical suspicion and imaging-based diagnosis or exclusion of VTE, were analyzed. Patients with PE received whole-leg ultrasonography to assess presence of DVT. Regularized logistic regression identified features that discriminate between isolated PE and other VTE phenotypes at clinical presentation. Survival analyses were performed to evaluate the crude and adjusted 3-year risks of arterial thrombotic disease, recurrent VTE, and death.

RESULTS

The sample comprised 510 patients. Isolated PE patients (n = 63) had a distinct clinical profile from patients with other VTE phenotypes (n = 447). COPD, peripheral artery disease, atrial fibrillation, and coronary artery disease were significantly more prevalent among patients with isolated PE. Isolated PE patients had significantly higher risk (incidence rate ratio vs DVT-associated PE, 3.7 (95% CI, 1.3-10.8, P = .009); vs isolated DVT, 4.8 (1.7-14.3, P = .001) of arterial thrombotic events (ie, myocardial infarction, stroke/transient ischemic attack). After adjustment for clinical profile and medication intake, the risk of arterial thrombotic events for patients with isolated PE remained quadruple that of other VTE phenotypes (hazard ratio [HR], 3.8 [1.3-10.9], P = .01).

INTERPRETATION

Patients with isolated PE are at higher risk for arterial thrombosis and may require screening for arterial disease and development of novel therapeutic strategies.

CLINICAL TRIAL REGISTRATION

NCT02156401.

Impact of respiratory symptoms and oxygen saturation on the risk of incident venous thromboembolism-the Tromsø study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with risk of venous thromboembolism (VTE). It remains unknown whether individual respiratory symptoms and lowered oxygen saturation (SpO2), individually and in combination with COPD, affect the risk of VTE.

OBJECTIVES

To investigate whether measures of respiratory impairments including respiratory symptoms and SpO2, individually and combined with COPD, were associated with an increased risk of VTE.

METHODS

Spirometry, SpO2, and self-reported respiratory symptoms were collected in 8686 participants from the fifth (2001-2002) and sixth (2007-2008) surveys of the Tromsø Study. Incident VTE events were registered from the date of inclusion to December 31, 2016. Cox regression models with exposures and confounders as time-varying covariates (for repeated measurements) were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for VTE.

RESULTS

During a median follow-up of 9.1 years, 330 participants developed incident VTE. Subjects with SpO2 ≤ 96% (lowest 20th percentile) had a 1.5-fold higher risk of VTE (adjusted HR, 1.48; 95% CI, 1.13-1.93) compared with those with SpO2 ≥ 98%. Severe respiratory symptoms (dyspnea, cough, and phlegm) were associated with a 1.4- to 2.0-fold higher risk of VTE compared with no such symptoms. COPD, combined with respiratory symptoms or lowered SpO2, had an additive effect on the VTE risk.

CONCLUSIONS

Lowered SpO2 and severe respiratory symptoms were associated with increased VTE risk. COPD combined with respiratory impairments had an additive effect on VTE risk, and may suggest particular attention on VTE preventive strategies in COPD patients with respiratory impairments.

Dissection of Pharmacological Mechanism of Chinese Herbal Medicine Yihuo Huatan Formula on Chronic Obstructive Pulmonary Disease: A Systems Pharmacology-Based Study

Chronic obstructive pulmonary disease (COPD) is one of the most common respiratory diseases. Yihuo Huatan Formula (YHF), as a proven Chinese Herbal Medicine (CHM), has been verified to be effective in the treatment of stable COPD through years' of practice. Nevertheless, its working mechanism is still unclear. We sought to systematically decipher the mechanism of YHF for treating stable COPD using systems pharmacology-based method that integrates pharmacokinetic screening, target prediction, network analyses, GO and KEGG enrichment analyses. Firstly, a total of 1267 chemicals out of 15 herbal components were included in YHF chemical database. Among them, 180 potential active molecules were screened out through pharmacokinetic evaluation. Then 258 targets of the active molecules were predicted, of which 84 were chosen for further analyses. Finally, the network analyses and GO and KEGG enrichment methods suggested a therapeutic effect of YHF on the alleviation of airway inflammation, decrease of mucus secretion, maintenance of immune homeostasis and benefit of COPD comorbidities, by regulating multiple targets and pathways. The systems pharmacology-based approach helps to understand the underlying working mechanism of YHF in stable COPD from a holistic perspective, and offers an exemplification for systematically uncovering the action mechanisms of CHM.

Association between features of COPD and risk of venous thromboembolism

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is associated with risk of venous thromboembolism (VTE) events. A detailed understanding of which clinical features of COPD increase risk of VTE events is needed.

OBJECTIVES

To investigate the association between features of COPD and risk of venous thromboembolism.

METHODS

A retrospective observational clinical study was conducted on 551 consecutive COPD patients visiting the Department of Respiratory and Critical Care Medicine of Tianjin Chest Hospital between February 2014 and April 2018. Finally, 151 patients were eligible for inclusion. Of these, 29 patients had COPD with VTE and 121 patients had COPD without VTE. Patient informations regarding age, gender, BMI, smoking history, smoking status (package/year), COPD-related symptoms, lung function, number of acute exacerbations and imaging visual emphysema were gathered.

RESULTS

Among the 29 VTE patients, 18 patients had PE and five had DVT, while 6 patients had simultaneous PE and DVT. There were statistically significant differences in GOLD grade, Imaging visual emphysema, and frequent acute exacerbations between the two groups. Multivariate logistic regression analysis showed that after adjustment for gender, age, BMI and smoking history, there were statistically significant for visible emphysema (OR = 3.54, 95% CI: 1.13-11.08; P = 0.03) and GOLD grade (OR = 1.77, 95% CI: 1.04-3.01; P = 0.035), but not for frequent acute exacerbations (OR = 1.65, 95% CI: 0.62-4.38; P = 0.31).

CONCLUSIONS

Visual emphysema is an independent risk factor for VTE events and the risk of VTE in COPD patients increases with the degree of airway obstruction. However, there is no evidence of an association between exacerbation frequency and VTE events.

Recurrence Risk after First Symptomatic Distal versus Proximal Deep Vein Thrombosis According to Baseline Risk Factors

Background  It remains unclear whether the distal location of deep vein thrombosis (DVT) is independently associated with a lower risk of recurrence in all patients, or represents a marker of the presence and severity of provoking factors for venous thromboembolism (VTE).

Methods  We investigated the impact of distal (vs. proximal) DVT location on the risk of developing symptomatic, objectively confirmed recurrent VTE in 831 patients with a first acute symptomatic DVT not associated with pulmonary embolism (PE), who were stratified by the presence of transient or persistent risk factors at baseline. The primary outcome was symptomatic, objectively diagnosed recurrent VTE, including proximal DVT and PE.

Results  A total of 205 (24.7%) patients presented with a transient risk factor, 189 (22.7%) with a minor persistent risk factor, 202 (24.3%) with unprovoked DVT, and 235 (28.3%) with cancer-associated DVT. One-hundred twenty-five patients (15.0%) experienced recurrent DVT or PE. The largest relative difference between patients with distal (vs. proximal) DVT was observed in the absence of identifiable risk factors (adjusted hazard ratio [aHR]: 0.11; 95% CI [confidence interval]: 0.03–0.45). In patients with cancer, distal and proximal DVT had a comparable risk of recurrence (aHR: 0.70; 95% CI: 0.28–1.78]).

Conclusions  The distal (vs. proximal) location of first acute symptomatic DVT represented, in the absence of any identifiable transient or persistent risk factors, a favorable prognostic factor for recurrence. In contrast, the prognostic impact of DVT location was weaker if persistent provoking risk factors for VTE were present, notably cancer.

Impact of chronic obstructive pulmonary disease on the outcomes of patients with peripheral artery disease

BACKGROUND

Peripheral artery disease (PAD) and chronic obstructive pulmonary disease (COPD) are both related with high in-hospital mortality. We aimed to investigate the impact of COPD on the in-hospital outcomes in PAD.

METHODS

PAD patients were selected based on ICD-code I70.2 of the German nationwide database, stratified for COPD and compared regarding adverse in-hospital outcomes.

RESULTS

Between 01/2005-12/2015, 5,611,827 inpatients (64.8% males) were diagnosed with PAD; of those, 13.6% were coded additionally with COPD. Overall, 277,894 PAD patients (5.0%) died during in-hospital course. Prevalence of cardiovascular diseases as well as cancer (12.1% vs. 7.0%, P < 0.001) was higher in PAD patients with COPD compared to PAD patients without COPD. PAD patients with COPD showed more often lower PAD stages according to Fontaine classification (PAD stage I: 27.1% vs. 19.3%, P < 0.001; PAD stage IIa: 34.9% vs. 35.5%, P < 0.001; PAD stage IIb: 14.5% vs. 13.6%, P < 0.001; PAD stage III: 11.8% vs. 14.8%, P < 0.001; PAD stage IV: 13.8% vs. 19.6%, P < 0.001). The all-cause in-hospital mortality was significantly higher in PAD patients with COPD compared to those without COPD (6.5% vs. 4.7%, P < 0.001). Cardiovascular events comprising pulmonary embolism and myocardial infarction occurred more often in coprevalence with PAD and COPD. COPD was an independent predictor of in-hospital death (OR 1.16 (95%CI 1.15-1.17) P < 0.001) and an independent predictor for pulmonary embolism (PE, OR 1.44 (1.40-1.49), P < 0.001) in PAD patients.

CONCLUSION

COPD was associated with a high in-hospital mortality in PAD patients probably driven by higher frequencies of PE and cancer.

Pulmonary Embolism in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Objective

In most countries, nearly 6% of the adults are suffering from chronic obstructive pulmonary disease (COPD), which puts a huge economic burden on the society. Moreover, COPD has been considered as an independent risk factor for pulmonary embolism (PE). In this review, we summarized the existing evidence that demonstrates the associations between COPD exacerbation and PE from various aspects, including epidemiology, pathophysiological changes, risk factors, clinical features, management, and prognosis.

Data Sources

We searched the terms "chronic obstructive pulmonary disease," "pulmonary embolism," "exacerbations," and "thromboembolic" in PubMed database and collected the results up to April 2018. The language was limited to English.

Study Selection

We thoroughly examined the titles and abstracts of all studies that met our search strategy. The data from prospective studies, meta-analyses, retrospective studies, and recent reviews were selected for preparing this review.

Results

The prevalence of PE in patients with COPD exacerbation varied a lot among different studies, mainly due to the variations in race, sample size, study design, research setting, and enrollment criteria. Overall, whites and African Americans showed significantly higher prevalence of PE than Asian people, and the hospitalized patients showed higher prevalence of PE compared to those who were evaluated in emergency department. PE is easily overlooked in patients with COPD exacerbation due to the similar clinical symptoms. However, several factors have been identified to contribute to the increased risk of PE during COPD exacerbation. Obesity and lower limb asymmetry were described as independent predictors for PE. Moreover, due to the high risk of PE, thromboprophylaxis has been used as an important treatment for hospitalized patients with COPD exacerbation.

Conclusions

According to the previous studies, COPD patients with PE experienced an increased risk of death and prolonged length of hospital stay. Therefore, the thromboembolic risk in patients with acute exacerbation of COPD, especially in the hospitalized patients, should carefully be evaluated.

Cardiovascular disease and COPD: dangerous liaisons?

Chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD) frequently occur together and their coexistence is associated with worse outcomes than either condition alone. Pathophysiological links between COPD and CVD include lung hyperinflation, systemic inflammation and COPD exacerbations. COPD treatments may produce beneficial cardiovascular (CV) effects, such as long-acting bronchodilators, which are associated with improvements in arterial stiffness, pulmonary vasoconstriction, and cardiac function. However, data are limited regarding whether these translate into benefits in CV outcomes. Some studies have suggested that treatment with long-acting β₂-agonists and long-acting muscarinic antagonists leads to an increase in the risk of CV events, particularly at treatment initiation, although the safety profile of these agents with prolonged use appears reassuring. Some CV medications may have a beneficial impact on COPD outcomes, but there have been concerns about β-blocker use leading to bronchospasm in COPD, which may result in patients not receiving guideline-recommended treatment. However, there are few data suggesting harm with these agents and patients should not be denied β-blockers if required. Clearer recommendations are necessary regarding the identification and management of comorbid CVD in patients with COPD in order to facilitate early intervention and appropriate treatment.

Pulmonary Embolism Among Patients With Acute Exacerbation Of Chronic Obstructive Pulmonary Disease: Implications For Emergency Medicine

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. Common in COPD are acute exacerbations (AE-COPD) that cause acute dyspnea, cough, and bronchospasm. Symptoms of AE-COPD mimic pulmonary embolism (PE).

METHODS

We conducted a systematic review of the literature to assess the prevalence of PE in patients admitted to the hospital with a clinical diagnosis of AE-COPD. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, we queried PubMed and MEDLINE databases from 1990 to 2017. The search term "prevalence pulmonary embolism, COPD" was used, and Boolean operators were used to combine search terms. Data were extracted from each article, specifically the sample size, study setting, design, and the prevalence of PE.

RESULTS

A total of 5 articles were included that demonstrated a prevalence of PE among patients with a clinical diagnosis of AE-COPD that ranged from 3.3-29.1%. Sample sizes varied from 49-197 patients. Studies occurred in both emergency department and inpatient settings, including intensive care units. Among the studies that reported patient characteristics associated with PE in AE-COPD, both obesity and immobility were important.

CONCLUSION

Studies reporting the prevalence of PE during AE-COPD vary considerably in their methods and results. Because of the relatively high prevalence of PE during AE-COPD, it is important for providers to be aware of this linkage between the 2 conditions and to screen patients using clinical gestalt and validated screening tools until more emergency department data are available.

Lack of association between airflow limitation and recurrence of venous thromboembolism among cancer patients with pulmonary embolism

Background

COPD is a well-known risk factor for venous thromboembolism (VTE) development. However, recent data showed that it was not associated with VTE recurrence risk, which excluded cancer patients. This study investigated the association of airflow limitation and VTE recurrence in cancer patients with pulmonary embolism (PE).

Methods

This is a retrospective cohort study of cancer patients with newly diagnosed PE at a university hospital. PE was confirmed using contrast-enhanced computed tomography scan. Airflow limitation was defined as pre-bronchodilator forced expiratory volume in 1 second (FEV₁)/forced vital capacity (FVC) <0.7 within 2 years of PE diagnosis. VTE recurrence was defined as a composite of recurrence as PE or deep vein thrombosis or both.

Results

Among 401 cancer patients with newly diagnosed PE, spirometry-based airflow limitation was observed in 126 (31.4%) patients. Half of the patients had lung cancer, which was more common in the group with airflow limitation (65.1% vs 42.9%, p < 0.001). Symptomatic PE was present in less than half (45.4%) of the cases, and 62.6% of patients were treated for PE. During the median follow-up period of 9.7 months, VTE recurred in 49 (12.2%) patients. Compared with patients without airflow limitation, those with airflow limitation did not have an increased risk of VTE recurrence in univariate or multivariate analyses (adjusted hazard ratio, 1.29 [95% CI 0.68, 2.45]).

Conclusion

The presence of airflow limitation did not increase the risk of VTE recurrence in cancer patients with PE. Prospective studies are needed to validate this finding.

Thromboelastometry and Platelet Function during Acclimatization to High Altitude

Interaction between hypoxia and coagulation is important given the increased risk of thrombotic diseases in chronically hypoxic patients who reside at sea level and in residents at high altitude. Hypoxia alters the proteome of platelets favouring a prothrombotic phenotype, but studies of activation and consumption of specific coagulation factors in hypoxic humans have yielded conflicting results. We tested blood from 63 healthy lowland volunteers acclimatizing to high altitude (5,200 m) using thromboelastometry and assays of platelet function to examine the effects of hypoxia on haemostasis. Using data from two separate cohorts of patients following identical ascent profiles, we detected a significant delay in clot formation, but increased clot strength by day 7 at 5,200 m. The latter finding may be accounted for by the significant rise in platelet count and fibrinogen concentration that occurred during acclimatization. Platelet function assays revealed evidence of platelet hyper-reactivity, with shortened PFA-100 closure times and increased platelet aggregation in response to adenosine diphosphate. Post-expedition results were consistent with the normalization of coagulation following descent to sea level. These robust findings indicate that hypoxia increases platelet reactivity and, with the exception of the paradoxical delay in thromboelastometry clotting time, suggest a prothrombotic phenotype at altitude. Further work to elucidate the mechanism of platelet activation in hypoxia will be important and could impact upon the management of patients with acute or chronic hypoxic respiratory diseases who are at risk of thrombotic events.

Intrapulmonary arteriovenous anastomoses in humans with chronic obstructive pulmonary disease: implications for cryptogenic stroke?

What is the central question of this study? Do individuals with chronic obstructive pulmonary disease have blood flow through intrapulmonary arteriovenous anastomoses at rest or during exercise? What is the main finding and its importance? Individuals with chronic obstructive pulmonary disease have a greater prevalence of blood flow through intrapulmonary arteriovenous anastomoses at rest than age-matched control subjects. Given that the intrapulmonary arteriovenous anastomoses are large enough to permit venous emboli to pass into the arterial circulation, patients with chronic obstructive pulmonary disease and an elevated risk of thrombus formation may be at risk of intrapulmonary arteriovenous anastomosis-facilitated embolic injury (e.g. stroke or transient ischaemic attack). The pulmonary capillaries prevent stroke by filtering venous emboli from the circulation. Intrapulmonary arteriovenous anastomoses are large-diameter (≥50 μm) vascular connections in the lung that may compromise the integrity of the pulmonary capillary filter and have recently been linked to cryptogenic stroke and transient ischaemic attack. Prothrombotic populations, such as individuals with chronic obstructive pulmonary disease (COPD), may be at increased risk of stroke and transient ischaemic attack facilitated by intrapulmonary arteriovenous anastomoses, but the prevalence and degree of blood flow through intrapulmonary arteriovenous anastomoses in this population has not been fully examined and compared with age-matched healthy control subjects. We used saline contrast echocardiography to assess blood flow through intrapulmonary arteriovenous anastomoses at rest (n = 29 COPD and 19 control subjects) and during exercise (n = 10 COPD and 10 control subjects) in subjects with COPD and age-matched healthy control subjects. Blood flow through intrapulmonary arteriovenous anastomoses was detected in 23% of subjects with COPD at rest and was significantly higher compared with age-matched healthy control subjects. Blood flow through intrapulmonary arteriovenous anastomoses at rest was reduced or eliminated in subjects with COPD after breathing hyperoxic gas. Sixty per cent of subjects with COPD who did not have blood flow through the intrapulmonary arteriovenous anastomoses at rest had blood flow through them during exercise. The combination of blood flow through intrapulmonary arteriovenous anastomoses and potential for thrombus formation in individuals with COPD may permit venous emboli to pass into the arterial circulation and cause stroke and transient ischaemic attack. Breathing supplemental oxygen may reduce this risk in COPD. The link between blood flow through intrapulmonary arteriovenous anastomoses, stroke and transient ischaemic attack is worthy of future investigation in COPD and other populations.

Risk of recurrent venous thromboembolism in COPD patients: results from a prospective cohort study

We aimed to assess the risk of recurrent venous thromboembolism (VTE) in patients with chronic obstructive pulmonary disease (COPD) following cessation of anticoagulation therapy.In a prospective cohort of 1468 patients with a documented episode of VTE, followed for up to 5 years after cessation of anticoagulation therapy, the diagnosis of COPD was confirmed in 136. The main outcome was recurrent VTE. The secondary outcome was overall mortality. Univariate and multivariate analyses were performed to identify the risk factors of recurrence.Of the 1468 patients included, recurrent VTE was observed in 306 (34 with COPD and 272 without) during a median follow-up period of 36.5 months. The incidence rate of recurrent VTE was 9.1% (95% CI 6.5-12.8) for COPD patients and 7.0% (95% CI 6.2-7.9) for non-COPD patients. COPD was not associated with an increased risk of VTE recurrence on univariate or multivariate analyses (hazard ratio: 1.0 (95% CI 0.7-1.4)). The risk of death, adjusted for demographic and clinical characteristics, showed no increase in COPD patients, as compared to non-COPD patients.In patients with COPD who had an acute episode of VTE, the risk of recurrent VTE was not any higher than that in non-COPD patients.

Survival and recurrent venous thromboembolism in patients with first proximal or isolated distal deep vein thrombosis and no pulmonary embolism

Essentials The long-term risk of recurrence and death after distal deep vein thrombosis (DVT) is uncertain. We included subjects with first proximal or isolated distal DVT (IDDVT) and no pulmonary embolism. The risk of symptomatic and asymptomatic recurrence is lower after IDDVT (vs. proximal). IDDVT may be associated with a lower long-term risk of death, especially after unprovoked DVT.

SUMMARY

Background A few studies have focused on the risk of recurrence after first acute isolated distal deep vein thrombosis (IDDVT) compared with proximal DVT (PDVT), whereas the incremental risk of death has never been explored beyond the first 3 years after acute event. Methods Our single-center cohort study included patients with first symptomatic acute PDVT or IDDVT. Patients were excluded if they had concomitant pulmonary embolism (PE) or prior venous thromboembolism. The primary outcomes were symptomatic objectively diagnosed recurrent PDVT or PE and all-cause death. Results In total, 4759 records were screened and 831 subjects included: 202 had symptomatic IDDVT and 629 had PDVT. The median age was 66 years and 50.5% were women. A total of 125 patients had recurrent PDVT or PE during 3175 patient-years of follow-up: 109 events occurred after PDVT (17.3%) and 16 after IDDVT (7.9%). Annual recurrence rates were 4.5% (95% confidence interval [CI], 3.7-5.4%) and 2.0% (95% CI, 1.1-3.2%), respectively, for an adjusted hazard ratio (aHR) for IDDVT patients of 0.32 (95% CI, 0.19-0.55). Death occurred in 263 patients (31.6% [95% CI, 28.6-34.9%]) during 5469 patient-years of follow-up for an overall annual incidence rate of 4.8% (95% CI, 4.2-5.4%). The mortality rate was 33.5% (n = 211) in PDVT patients and 25.7% (n = 52) in IDDVT patients. The long-term hazard of death appeared lower for IDDVT patients (aHR, 0.75 [95% CI, 0.55-1.02]), especially after unprovoked events (aHR, 0.58 [95% CI, 0.26-1.31]). Conclusions Compared with PDVT, IDDVT patients were at a lower risk of recurrent VTE. The risk of death appeared lower after IDDVT during a median follow-up of 7.6 years.

Lung function, respiratory symptoms and venous thromboembolism risk: the Atherosclerosis Risk in Communities Study

Essentials The association of lung function with venous thromboembolism (VTE) is unclear. Chronic obstructive pulmonary disease (COPD) patterns were associated with a higher risk of VTE. Symptoms were also associated with a higher risk of VTE, but a restrictive pattern was not. COPD may increase the risk of VTE and respiratory symptoms may be a novel risk marker for VTE.

SUMMARY

Background The evidence for the association between chronic obstructive pulmonary disease (COPD) and venous thromboembolism (VTE) is limited. There is no study investigating the association between restrictive lung disease (RLD) and respiratory symptoms with VTE. Objectives To investigate prospectively the association of lung function and respiratory symptoms with VTE. Patients/Methods In 1987-1989, we assessed lung function by using spirometry, and obtained information on respiratory symptoms (cough, phlegm, and dyspnea) in 14 654 participants aged 45-64 years, without a history of VTE or anticoagulant use, and followed them through 2011. Participants were classified into four mutually exclusive groups: 'COPD' (forced expiratory volume in 1 s [FEV1 ]/forced vital capacity [FVC] below the lower limit of normal [LLN]), 'RLD' (FEV1 /FVC ≥ LLN and FVC < LLN), 'respiratory symptoms with normal spirometic results' (without RLD or COPD), and 'normal' (without respiratory symptoms, RLD, or COPD). Results We documented 639 VTEs (238 unprovoked and 401 provoked VTEs). After adjustment for VTE risk factors, VTE risk was increased for individuals with either respiratory symptoms with normal spirometric results (hazard ratio [HR] 1.40, 95% confidence interval [CI] 1.12-1.73) or COPD (HR 1.33, 95% CI 1.07-1.67) but not for those with RLD (HR 1.15, 95% CI 0.82-1.60). These elevated risks of VTE were derived from both unprovoked and provoked VTE. Moreover, FEV1 and FEV1 /FVC showed dose-response relationships with VTE. COPD was more strongly associated with pulmonary embolism than with deep vein thrombosis. Conclusions Obstructive spirometric patterns were associated with an increased risk of VTE, suggesting that COPD may increase the risk of VTE. Respiratory symptoms may represent a novel risk marker for VTE.

Venous thromboembolism in medical patients during hospitalisation and 3 months after hospitalisation: a prospective observational study

OBJECTIVES

This study was conducted to assess the incidence and risk factors for venous thromboembolism (VTE) in a cohort of medical patients both during the period of hospitalisation and following discharge.

DESIGN

This was a prospective observational study to document the risk profile and incidence of VTE posthospitalisation among all medical patients admitted to our institution during the trial period.

SETTINGS

Primary healthcare. Single tertiary referral centre, Tasmania, Australia.

PARTICIPANTS

A total of 986 patients admitted to the medical ward between January 2012 and September 2012 were included in the study with male to female ratio of 497:489. The mean age of patients was 68 years (range 17-112, SD 16).

RESULTS

Overall, 54/986 patients (5.5%) had a VTE during the study period. Of these, 40/54 (74.1%) occurred during hospitalisation and 14/54 (25.9%) occurred following discharge. VTE risk factors revealed in multivariate analysis to be associated with a previous diagnosis of VTE (p<0.001, OR=6.63, 95% CI 3.3 to 13.36), the occurrence of surgery within the past 30 days (p<0.001, OR=2.52, 95% CI 1.33 to 4.79) and an admission diagnosis of pulmonary disease (p<0.01, OR 3.61, 95% CI 1.49 to 8.76). Mobility within 24 hours of admission was not associated with an increased risk. There was risk of VTE when the length of stay prolonged (p=0.046, OR=1.01, 95% CI 1.00 to 1.03), however it was not sustained with multivariate modelling. VTE-specific prophylaxis was used in 53% of the studied patients. Anticoagulation including antiplatelet agents were administered in 63% of patients who developed VTE.

CONCLUSIONS

This prospective observational study found that 5.5% of the studied patients developed VTE. Among those, 25.9% (14/54) of patients had a detected VTE posthospitalisation with this risk being increased if there was a history of VTE, recent surgery and pulmonary conditions. Thromboprophylaxis may be worth considering in these cohorts. Further study to confirm these findings are warranted.

TRIAL REGISTRATION NUMBER

ACTRN12611001255976.