Repeated measurements of carotid atherosclerosis and future risk of venous thromboembolism: the Tromsø Study.

Essentials The relationship between atherosclerosis and venous thromboembolism (VTE) is controversial. In total, 10 426 participants recruited from the general population were included. Carotid intima media thickness and total plaque area was not associated with VTE. There was no association between plaque initiation or plaque progression and subsequent VTE. SUMMARY: Background Whether a relationship between atherosclerosis and subsequent venous thromboembolism (VTE) exists is controversial. Objective To investigate the association between carotid atherosclerosis and VTE by using repeated measurements of intima media thickness (IMT) and total plaque area (TPA) in participants recruited from the general population. Methods Participants were recruited from the fourth (1994-1995), fifth (2001-2002) and sixth (2007-2008) surveys of the Tromsø Study. In total, 10 426 participants attended, for whom measurements of carotid IMT and TPA and potential confounders were updated at each available survey. Time-varying Cox regression models were used to calculate hazard ratios (HRs) of VTE across various levels of IMT and TPA adjusted for age, sex, and body mass index. Results There were 368 incident VTE events during a median follow-up of 10.8 years. Participants with increasing IMT were, on average, older and had a less favorable cardiovascular risk profile. There was no association between tertiles of increasing TPA and the risk of VTE in the time-varying model, and increasing IMT was not associated with an increased risk of VTE (HR 0.96, 95% confidence interval [CI] 0.86-1.07). Neither plaque formation nor plaque progression was associated with the risk of VTE (respectively: HR 1.00, 95% CI 0.98-1.02; and HR 0.96, 95% CI 0.84-1.11). Conclusion Carotid IMT and TPA were not associated with an increased risk of VTE in time-varying analyses. Furthermore, there was no association between plaque initiation or plaque progression and subsequent VTE.

Impact of incident myocardial infarction on the risk of venous thromboembolism: the Tromsø Study.

UNLABELLED: Essentials Registry-based studies indicate a link between arterial- and venous thromboembolism (VTE). We studied this association in a cohort with confounder information and validated outcomes. Myocardial infarction (MI) was associated with a 4.8-fold increased short-term risk of VTE. MI was associated with a transient increased risk of VTE, and pulmonary embolism in particular. SUMMARY: Background Recent studies have demonstrated an association between venous thromboembolism (VTE) and arterial thrombotic diseases. Objectives To study the association between incident myocardial infarction (MI) and VTE in a prospective population-based cohort. Methods Study participants (n = 29 506) were recruited from three surveys of the Tromsø Study (conducted in 1994-1995, 2001-2002, and 2007-2008) and followed up to 2010. All incident MI and VTE events during follow-up were recorded. Cox regression models with age as the time scale and MI as a time-dependent variable were used to calculate hazard ratios (HRs) of VTE adjusted for sex, body mass index, blood pressure, diabetes mellitus, HDL cholesterol, smoking, physical activity, and education level. Results During a median follow-up of 15.7 years, 1853 participants experienced an MI and 699 experienced a VTE. MI was associated with a 51% increased risk of VTE (HR 1.51; 95% confidence interval [CI] 1.08-2.10) and a 72% increased risk of pulmonary embolism (PE) (HR 1.72; 95% CI 1.07-2.75), but not significantly associated with the risk of deep vein thrombosis (DVT) (HR 1.36; 95% CI 0.86-2.15). The highest risk estimates for PE were observed during the first 6 months after the MI (HR 8.49; 95% CI 4.00-18.77). MI explained 6.2% of the PEs in the population (population attributable risk) and 78.5% of the PE risk in MI patients (attributable risk). Conclusions Our findings indicate that MI is associated with a transient increased VTE risk, independently of traditional atherosclerotic risk factors. The risk estimates were particularly high for PE.

Atrial fibrillation and future risk of venous thromboembolism:the Tromsø study.

AIMS: Whether atrial fibrillation is related to risk of venous thromboembolism (VTE) has not been extensively studied. Therefore, we investigated the association between atrial fibrillation and future risk of VTE in a population-based cohort. METHODS: In total, 29,975 subjects were recruited from three surveys of the Tromsø study and followed from enrollment (1994-1995, 2001-2002 and 2007-2008) up to 2010. Incident events of atrial fibrillation and VTE during follow-up were recorded. Information on potential confounders was obtained at baseline. Cox-regression models with atrial fibrillation as time-dependent variable were used to calculate hazard ratios (HRs) for VTE with 95% confidence intervals (CIs). RESULTS: During 16 years of median follow-up, 1604 subjects were diagnosed with atrial fibrillation and 614 with incident VTE. The risk of VTE was substantially increased during the first 6 months after diagnosis of atrial fibrillation (HR, 8.44; 95% CI, 5.61-12.69), and remained increased throughout the study period (HR, 1.43; 95% CI, 1.43-1.99) compared with those without atrial fibrillation. Atrial fibrillation displayed higher risk estimates for pulmonary embolism (HR, 11.84; 95% CI, 6.80-20.63) than for deep vein thrombosis (HR, 6.20; 95% CI, 3.37-11.39) during the first 6 months, and was still associated with pulmonary embolism (HR, 1.96; 95% CI, 1.24-3.10) but not with deep vein thrombosis (HR, 1.08; 95% CI, 0.66-1.75) more than 6 months after diagnosis. CONCLUSION: Atrial fibrillation was associated with increased risk of VTE, and pulmonary embolism in particular. Our findings support the concept that isolated pulmonary embolism may originate from right atrial thrombi due to atrial fibrillation.