Efficacy and safety of dabigatran etexilate and warfarin in "real-world" patients with atrial fibrillation: a prospective nationwide cohort study.

OBJECTIVES: The aim of this study was to assess the efficacy and safety in an "everyday clinical practice" population of anticoagulant-naïve patients with atrial fibrillation (AF) treated with dabigatran etexilate after its post-approval availability in Denmark, compared with warfarin. BACKGROUND: Concerns have been raised about an excess of bleeding events or myocardial infarction (MI) among patients treated with the new oral direct thrombin inhibitor, dabigatran etexilate. METHODS: From the Danish Registry of Medicinal Product Statistics, we identified a dabigatran-treated group and a 1:2 propensity-matched warfarin-treated group of 4,978 and 8,936, respectively. Comparisons on efficacy and safety outcomes were made on the basis of Cox-proportional hazards models stratified on propensity-matched groups. RESULTS: Stroke and systemic embolism were not significantly different between warfarin- and dabigatran-treated patients. Adjusted mortality was significantly lower with both dabigatran doses (110 mg b.i.d., propensity-match group stratified hazard ratio [aHR]: 0.79, 95% confidence interval [CI]: 0.65 to 0.95; 150 mg b.i.d., aHR: 0.57, 95% CI: 0.40 to 0.80), when compared with warfarin. Pulmonary embolism was lower compared with warfarin for both doses of dabigatran. Less intracranial bleeding was seen with both dabigatran doses (110 mg b.i.d., aHR: 0.24, 95% CI: 0.08 to 0.56; 150 mg b.i.d., aHR: 0.08, 95% CI: 0.01 to 0.40). The incidence of MI was lower with both dabigatran doses (110 mg b.i.d., aHR: 0.30, 95% CI: 0.18 to 0.49; 150 mg b.i.d., aHR: 0.40, 95% CI: 0.21 to 0.70). Gastrointestinal bleeding was lower with dabigatran 110 mg b.i.d. (aHR: 0.60, 95% CI: 0.37 to 0.93) compared with warfarin but not dabigatran 150 mg b.i.d. The main findings were broadly consistent in a subgroup analysis of dabigatran users with ≥1-year follow-up (median follow-up 13.9 months [interquartile range: 12.6 to 15.3 months]). CONCLUSIONS: In this "everyday clinical practice" post-approval nationwide clinical cohort, there were similar stroke/systemic embolism and major bleeding rates with dabigatran (both doses) compared with warfarin. Mortality, intracranial bleeding, pulmonary embolism, and MI were lower with dabigatran, compared with warfarin. We found no evidence of an excess of bleeding events or MI among dabigatran-treated patients in this propensity-matched comparison against warfarin, even in the subgroup with ≥1-year follow-up.

Adipose tissue arachidonic acid content is associated with the expression of 5-lipoxygenase in atherosclerotic plaques.

BACKGROUND: The content of arachidonic acid in adipose tissue is positively associated with the risk of myocardial infarction, whereas the content of eicosapentaenoic acid in adipose tissue has been reported to be negatively associated with the risk of myocardial infarction. Both arachidonic acid and eicosapentaenoic acid are substrates for the synthesis of pro-inflammatory leukotrienes and leukotrienes derived from eicosapentaenoic acid are generally much less potent. In this study we hypothesized that a high content of arachidonic acid in adipose tissue would reflect a high formation of arachidonic acid derived leukotrienes and a high expression of 5-lipoxygenase in atherosclerotic plaques. Likewise, we hypothesized that a high content of eicosapentaenoic acid in adipose tissue would reflect a low formation of arachidonic acid derived leukotrienes and a low expression of 5-lipoxygenase in plaques. METHODS: In a cross sectional study we included 45 consecutive subjects undergoing femoral thrombendarterectomy. The expression of 5-lipoxygenase in plaques was assessed by a semi-automated image analysis computer programme after immunohistochemical staining with mono-clonal 5-lipoxygenase antibodies. Leukotriene B4 and cysteinyl leukotriene formation from stimulated femoral artery plaques was quantified using ELISA methods. The fatty acid content of adipose tissue biopsies from the thigh was analyzed using gas chromatography. Associations between variables were assessed by Pearson correlations and were further explored in a multivariable linear regression model adjusting for potential confounders. RESULTS: A high content of arachidonic acid in adipose tissue was associated with a higher expression of 5-lipoxygenase in plaques (r = 0.32, p = 0.03), but no significant associations with leukotriene B4 (r = 0.22, p = 0.14) and cysteinyl leukotriene (r = -0.11, p = 0.46) formation was seen. No significant associations were found between the content of eicosapentaenoic acid in adipose tissue and 5-lipoxygenase expression or leukotriene formation in plaque. CONCLUSIONS: Adipose tissue arachidonic acid contents correlated positively with the expression of 5-lipoxygenase in plaques. This association might represent a causal link between adipose tissue arachidonic acid and the risk of myocardial infarction but confirmatory studies are needed.

Added predictive ability of the CHA2DS2VASc risk score for stroke and death in patients with atrial fibrillation: the prospective Danish Diet, Cancer, and Health cohort study.

BACKGROUND: The objective of this study was to evaluate the added predictive ability of the CHA(2)DS(2)VASc prediction rule for stroke and death in a nonanticoagulated population of patients with atrial fibrillation. METHODS AND RESULTS: We included 1603 nonanticoagulated patients with incident atrial fibrillation from a Danish prospective cohort study of 57 053 middle-aged men and women. The Net Reclassification Improvement was calculated as a measure to estimate any overall improvement in reclassification with the CHA(2)DS(2)VASc sore as an alternative to the CHADS(2) score. After 1-year follow-up, crude incidence rates were 3.4 per 100 person-years for stroke and 13.6 for death. After a mean follow-up of 5.4 years (± 3.7 years), the crude incidence rates for stroke and death were 1.9 and 5.6, respectively. During the entire observation period, the c-statistics and negative predictive values were similar for both risk scores. The Net Reclassification Improvement analysis showed that 1 of 10 reclassified atrial fibrillation patients would have been upgraded correctly using the CHA(2)DS(2)VASc score. CONCLUSIONS: Both the CHADS(2) as well as the CHA(2)DS(2)VASc risk score can exclude a large proportion of patients from having high risk of stroke or death. However, using the CHA(2)DS(2)VASc risk score, fewer patients will fulfill the criterion for low risk (and are truly low risk for thromboembolism). For every 10 extra patients transferred to the treatment group at 5 years, using the CHA(2)DS(2)VASc risk score, 1 patient would have had a stroke that might have been avoided with effective treatment.

The NFKB1 ATTG ins/del polymorphism and risk of coronary heart disease in three independent populations.

AIM: Inflammation is a risk factor for coronary heart disease (CHD). A common deletion-allele in the promoter region of NFKB1 results in lower protein levels of the NF-κB p50 subunit. Recent evidence suggests that the NF-κB p50 dimer has anti-inflammatory effects. We aimed to investigate the association of the functional ATTG NFKB1 insertion/deletion variant with risk of CHD in three independent prospective studies of generally healthy men and women. METHODS AND RESULTS: The NFKB1 ins/del polymorphism was genotyped in studies of CHD nested within the Diet, Cancer and Health (DCH) study, the Health Professionals Follow-up (HPFS) and the Nurses' Health (NHS) studies, totaling 1008, 428 and 439 cases, respectively. The minor allele frequency in the combined sample was 0.38 among controls. In a pooled analysis, the relative risk (RR) among heterozygous men and women was 1.22 (95% CI: 1.07-1.40), compared to the most common ins/ins genotype. The RR among homozygotes was 1.20 (95% CI: 0.94-1.53). There was no evidence of an allele-dosage effect, and in a dominant model the RR among del-allele carriers was 1.22 (95% CI: 1.07-1.39). The risk was similar in women and men (RR was 1.20 in women and 1.23 in men, respectively). The NFKB1 variant was not associated with plasma lipid levels, but del-carriers had lower levels of C-reactive protein. CONCLUSIONS: The NFKB1 promoter variant, previously shown to cause partial depletion of NF-κB p50, was associated with a higher risk of CHD in three independent prospective studies of generally healthy Caucasians.