Atrial fibrillation (AF) substantially increases risk of stroke. Evidence suggests that anticoagulation to reduce risk is underused (a "care gap"). Our objectives were to clarify measures of this gap in care by including data from family physicians and to determine why eligible patients were not receiving anticoagulation therapy.
Telephone survey of family physicians regarding specific patients in their practices.
Ambulatory AF patients not taking warfarin who had risk factors that made anticoagulation appropriate.
Proportion of patients removed from the care gap; reasons given for not giving the remainder anticoagulants.
Half the patients thought to be in the care gap had previously unknown contraindications to anticoagulation, lacked a clear indication for anticoagulation, or were taking warfarin. Patients' refusal and anticipated problems with compliance and monitoring were among the reasons for not giving patients anticoagulants.
Adding data from primary care physicians significantly narrowed the care gap. Attention should focus on the remaining reasons for not giving eligible patients anticoagulants.
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Atrial fibrillation (AF) is the most common adult arrhythmia, and significantly increases the risk of ischemic stroke. Oral anticoagulation may be underused and may be less effective in community settings than clinical trial settings.
To determine the rates of thromboembolism and bleeding in an ambulatory cohort of patients with AF.
Observational study of Nova Scotian residents with AF identified by electrocardiogram in ambulatory settings between November 1999 and January 2001. Main outcome measures were rates of thromboembolism and bleeding over two years.
Four hundred twenty-five patients were included in the study. The mean (+/-SD) age was 70.6+/-11.1 years, and 40% were women. Warfarin therapy was used by 68% of patients. Sixty-two per cent of patients had hypertension, 21% had a previous stroke or transient ischemic attack, 44% had congestive heart failure and 20% were diabetic. The overall rate of thromboembolic events was 2.7% in warfarin users and 8.5% in nonwarfarin users over two years, with an RR reduction of 68% (OR 0.31, 95% CI 0.09 to 0.91; P=0.047). The annual rate of ischemic stroke was 1.2% and 3.1% in warfarin and nonwarfarin users, respectively, with an RR reduction of 62% (OR 0.29, 95% CI 0.08 to 1.04; P=0.057). The overall rate of major bleeding was 2.6% in warfarin users and 1.4% in nonwarfarin users (P=0.667). The annual mortality rate was 7.79% in warfarin users and 9.93% in nonwarfarin users (P=0.192).
Warfarin use was found to significantly reduce the rate of thromboembolic events without a concomitant increase in hemorrhagic events. The present study confirms the effectiveness of warfarin therapy in a population-based cohort.
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There is variation in cardiac catheterization utilization across jurisdictions. Previous work from Alberta, Canada, showed no evidence of a plateau in the yield of high-risk disease at cardiac catheterization rates as high as 600 per 100,000 population suggesting that the optimal rate is higher. This work aims 1) To determine if a previously demonstrated linear relationship between the yield of high-risk coronary disease and cardiac catheterization rates persists with contemporary data and 2) to explore whether the linear relationship exists in other jurisdictions.
Detailed clinical information on all patients undergoing cardiac catheterization in 3 Canadian provinces was available through the Alberta Provincial Project for Outcomes Assessment in Coronary Heart (APPROACH) disease and partner initiatives in British Columbia and Nova Scotia. Population rates of catheterization and high-risk coronary disease detection for each health region in these three provinces, and age-adjusted rates produced using direct standardization. A mixed effects regression analysis was performed to assess the relationship between catheterization rate and high-risk coronary disease detection.
In the contemporary Alberta data, we found a linear relationship between the population catheterization rate and the high-risk yield. Although the yield was slightly less in time period 2 (2002-2006) than in time period 1(1995-2001), there was no statistical evidence of a plateau. The linear relationship between catheterization rate and high-risk yield was similarly demonstrated in British Columbia and Nova Scotia and appears to extend, without a plateau in yield, to rates over 800 procedures per 100,000 population.
Our study demonstrates a consistent finding, over time and across jurisdictions, of linearly increasing detection of high-risk CAD as population rates of cardiac catheterization increase. This internationally-relevant finding can inform country-level planning of invasive cardiac care services.
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Oral anticoagulation is an effective therapy for the prevention of cardioembolic complications in patients with atrial fibrillation. However, previous practice reviews have indicated that oral anticoagulants are often underused in this setting. Most of those reports have focused on reviews of hospitalized and institutionalized patients, or small geographical areas.
To determine the use of antithrombotic therapy for the treatment of atrial fibrillation in Nova Scotia and to survey the knowledge of antithrombotic therapy for atrial fibrillation among a concurrent cohort of primary care and specialist physicians involved in the management of patients with atrial fibrillation.
Patients with atrial fibrillation were identified through outpatient electrocardiography clinics held throughout Nova Scotia. Following consent of the primary care physicians, patients were contacted and completed a survey about their current management. Family physicians and specialists in Nova Scotia were also surveyed about the management of atrial fibrillation with antithrombotic therapy through the receipt of one of four case scenarios.
Four hundred twenty-five patients participated in the cross-sectional survey. The mean patient age was 70.6 years, 255 (60%) were male and 398 (93.6%) had at least one risk factor for stroke in addition to atrial fibrillation. Two hundred ninety-four patients (69.2%) were receiving oral anticoagulants either alone (61.9%) or in combination with acetylsalicylic acid (ASA) (7.3%). An additional 85 patients (20%) received ASA alone. There was no difference in the rates of prescription of oral anticoagulants between elderly patients (75 years of age and older) and those younger than 75 years (71.7% versus 67.3%, 95% CI -13.1% to 4.5%; P=0.34). Overall, 72.0% of patients were receiving antithrombotic therapy in accordance with the 2001 guidelines of the American College of Chest Physicians, with no difference in the rates between individuals younger than 75 years (72.2%) and those over 75 years of age (71.7%) (absolute difference -0.5%, 95% CI -9.2% to 8.1%). Physician responses to case scenarios indicated that knowledge was high among both general practitioners and specialists regarding the appropriate use of oral anticoagulants for the prevention of thrombotic complications associated with atrial fibrillation.
The appropriate use of oral antithrombotic therapy for the prevention of thrombotic complications of atrial fibrillation occurs in approximately 72% of patients studied in Nova Scotia, and physician knowledge about this indication is high. There was no bias against prescribing oral anticoagulants to elderly patients. The findings suggest that with time, education and evidence have positively impacted the use of antithrombotic therapy in these patients.
It has previously been shown that the increased use of therapeutic intervention may not reduce patient fatality if there is a simultaneous increase in case severity. The present study was designed to extend the relationship between case severity and therapeutic interventions to long-term survival in the same study population.
To compare five-year survival of patients discharged after acute myocardial infarction from 1984 to 1988 and from 1989 to 1993, and to evaluate possible reasons for survival differences.
The present study was population-based. Survival time was determined by record linkage into the Canadian Mortality Database. Association of five-year survival with patient characteristics, in-hospital treatment and discharge medications was assessed by logistical regression analysis. Case severity was calculated as the probability of death within five years, given the patient profile and excluding any interventions.
Between the two study periods, most patient characteristics and treatment intensity changed, but case severity for the study population remained constant. Five-year survival improved from 74.8% to 79.2% (P(chi2)=0.001). The improvement was adequately described by the combination of changes in patient profile and treatment without residual period effect (P(goodness-of-fit)=0.752). The treatments significantly associated with five-year survival were coronary artery bypass graft surgery (OR 2.74; 95% CI 1.86 to 4.05), percutaneous coronary intervention (OR 2.63; 95% CI 1.67 to 4.14) and thrombolysis (OR 1.98; 95% CI 1.50 to 2.62) during admission, as well as acetylsalicylic acid (OR 1.39; 95% CI 1.15 to 1.68) or beta-blocker (OR 1.60; 95% CI 1.34 to 1.92) prescription at discharge.
Changes in patient profile did not affect long-term prognosis; instead, treatment modalities accounted for the observed improvement in five-year survival.
Department of Medicine, Queen Elizabeth II Health Sciences Center and the Department of Community Health and Epidemiology, Research Methods Unit, Dalhousie University, Halifax, Nova Scotia, Canada. email@example.com
Circ Arrhythm Electrophysiol. 2012 Aug 1;5(4):706-13
Underuse of implantable defibrillators has been previously noted in patients at risk for sudden cardiac death, as well as for survivors of sudden cardiac death. We sought to determine the utilization rates in a primary prevention implantable cardioverter-defibrillator (ICD)-eligible population and mortality in this group compared with a group that had undergone implantation of this therapy.
A retrospective cohort of patients from April 1, 2006, to December 31, 2009, was used to define a primary prevention ICD-eligible population. Two groups were compared on the basis of ICD implantation (no-ICD versus ICD). The primary outcome measure was mortality. Of the 717 patients found to be potentially eligible for a primary prevention ICD, 116 (16%) were referred. The remaining cohort of 601 patients were compared with an existing cohort of primary prevention ICD patients (n=290). A significant survival benefit was associated with primary prevention ICD implantation (hazard ratio, 0.46; 95% CI [0.33-0.64]; P
Comment In: Circ Arrhythm Electrophysiol. 2012 Aug 1;5(4):624-522895600