Age threshold for the use of non-vitamin K antagonist oral anticoagulants for stroke prevention in patients with atrial fibrillation: insights into the optimal assessment of age and incident comorbidities.

AIMS: The stroke risk of patients with atrial fibrillation (AF) is not static, since AF patients get older and accumulate more comorbidities after AF is diagnosed. Therefore, the stroke risk of AF patients given certain comorbidities in different age strata should ideally be analysed using an assessment which considers incident comorbidities and the actual age when ischaemic stroke occurred. The goal of the present study is to report the age treatment thresholds for the use of non-vitamin K antagonist oral anticoagulants (NOACs) for AF patients without or with only one comorbidity of the CHA2DS2-VASc score, based on an 'ideal method' of stroke risk assessments. METHODS AND RESULTS: The study cohort included 31 039 and 39 020 AF patients who did not have any or had only one risk factor comorbidity of the CHA2DS2-VASc score except for age and sex. The risks of ischaemic stroke in each age strata for each comorbidities were analysed in three ways, as follows: (i) the conventional way (based on baseline risk factors and age), (ii) dynamic method (patients were censored when new comorbidities occurred), and (iii) an ideal method (patients were censored when new comorbidities occurred and the stroke risk was related to the actual age when stroke happened). The tipping point for the use of NOACs was set at a stroke risk of 0.9%/year. The overall risk of ischaemic stroke using the conventional way was overestimated compared to the dynamic or ideal assessment with the incidence rate ratio of 1.24 for patients with hypertension, 1.20 for heart failure, 1.37 for diabetes mellitus, and 1.38 for vascular diseases; all P-values <0.01. The risk of ischaemic stroke for each age strata was generally higher with the conventional or dynamic methods compared with the ideal assessment. With heart failure, the tipping point (age 35 years) of NOACs was similar, irrespective of methods used for stroke risk assessment. According to the results of ideal assessment, the age thresholds for the use of NOACs for patients with hypertension, diabetes mellitus, and vascular diseases were 50 years, 50 years, and 55 years, respectively. CONCLUSION: Ischaemic stroke risk in AF is heterogeneous, depending on different risk factors with age being as an important driver of stroke risk. Age thresholds for the use of NOACs were different for AF patients having different single risk factors beyond sex despite the same CHA2DS2-VASc score point (1 for males and 2 for females); that is, 35 years for heart failure, 50 years for hypertension or diabetes, and 55 years for vascular diseases.

An observational study on the effect of premature ventricular complex burden on long-term outcome.

The long-term clinical impact of premature ventricular complexes (PVCs) on mortality and morbidity has not been fully studied. This study aimed to investigate the association between the burden of PVCs and adverse clinical outcome.A total of 5778 subjects, who were pacemaker-free and ventricular tachycardia-free at baseline, received 24-hour electrocardiography monitoring between January 1, 2002 and December 31, 2004. Clinical event data were retrieved from the Bureau of National Health Insurance of Taiwan. Multivariate Cox hazards regression models and propensity-score matching were applied to assess the association between PVCs and adverse clinical outcome.Average follow-up time was 10[REPLACEMENT CHARACTER]±â€Š1 year. In all, 1403 subjects expired, 1301 subjects were hospitalized in the cardiovascular (CV) ward, 3384 were hospitalized for any reason, and 631 subjects developed new-onset heart failure (HF). The optimal cut-off PVC frequency (12 beats per day) was obtained through receiver operator characteristic curves, with a sensitivity of 58.4% and specificity of 59.8%. Upon multivariate analysis, a PVC frequency >12 beats per day was an independent predictor for all mortality (hazard ratio [HR]: 1.429, 95% confidence interval [CI]: 1.284-1.590), CV hospitalization (HR: 1.127, 95% CI: 1.008-1.260), all-cause hospitalization (HR 1.094, 95% CI: 1.021-1.173), and new-onset HF (HR: 1.411, 95% CI: 1.203-1.655). Subjects with a PVC frequency >12 beats per day had an increased risk of cardiac death attributable to HF and sudden cardiac death. The incidence rates for mortality and HF were significantly increased in cases of raised PVC frequency. Propensity-score matching analysis also echoed the main findings.Increased PVC burden was associated with a higher incidence of all-cause mortality, CV hospitalization, all-cause hospitalization, and new-onset HF which was independent of other clinical risk factors.

Impact on Outcomes of Changing Treatment Guideline Recommendations for Stroke Prevention in Atrial Fibrillation: A Nationwide Cohort Study.

OBJECTIVE: To investigate the impact on outcomes of changing treatment guideline recommendations by comparing the proportion of patients with atrial fibrillation (AF) recommended oral anticoagulants (OACs) under the 2011 and 2014 American College of Cardiology/American Heart Association (ACC/AHA) guidelines. PATIENTS AND METHODS: We used the "National Health Insurance Research Database" in Taiwan, which included 354,649 patients with AF from January 1, 1996 through December 31, 2011. Patients with a CHADS2 (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, and prior stroke or transient ischemic attack) score of 2 or more and a CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack, vascular disease, age 65-74 years, female sex category) score of 2 or more were considered to have a definitive indication for receiving OACs according to the 2011 and 2014 ACC/AHA guidelines, respectively. RESULTS: The percentages of patients with AF recommended OACs increased from 69.3% (n=245,598) under the 2011 guideline to 86.7% (n=307,640) under the new 2014 guidelines, an increment of 17.5% (95% CI, 17.4-17.6). Most women with AF (94.1%) and patients older than 65 years (97.2%) would receive OACs on the basis of the 2014 guidelines. Among patients previously not being recommended OACs in older guidelines, OAC use under the new guidelines was associated with a lower risk of adverse outcomes (ischemic stroke or intracranial hemorrhage or bleeding requiring blood transfusion or mortality) with an adjusted hazard ratio of 0.89 (95% CI, 0.85-0.94). CONCLUSION: In this nationwide cohort study, use of the 2014 guidelines led more patients with AF to receive OACs for stroke prevention, and this increased OAC use was associated with better outcomes. Better efforts to implement guidelines would lead to improved outcomes for patients with AF.