IMPORTANCE Myocardial infarction (MI) is an established risk factor for atrial fibrillation (AF). However, the extent to which AF is a risk factor for MI has not been investigated. OBJECTIVE To ...examine the risk of incident MI associated with AF. DESIGN, SETTING, AND PARTICIPANTS A prospective cohort of 23 928 participants residing in the continental United States and without coronary heart disease at baseline were enrolled from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort between 2003 and 2007, with follow-up through December 2009. MAIN OUTCOMES AND MEASURES Expert-adjudicated total MI events (fatal and nonfatal). RESULTS Over 6.9 years of follow-up (median 4.5 years), 648 incident MI events occurred. In a sociodemographic-adjusted model, AF was associated with about 2-fold increased risk of MI (hazard ratio HR, 1.96 95% CI, 1.52-2.52). This association remained significant (HR, 1.70 95% CI, 1.26-2.30) after further adjustment for total cholesterol, high-density lipoprotein cholesterol, smoking status, systolic blood pressure, blood pressure–lowering drugs, body mass index, diabetes, warfarin use, aspirin use, statin use, history of stroke and vascular disease, estimated glomerular filtration rate, albumin to creatinine ratio, and C-reactive protein level. In subgroup analysis, the risk of MI associated with AF was significantly higher in women (HR, 2.16 95% CI, 1.41-3.31) than in men (HR, 1.39 95% CI, 0.91-2.10) and in blacks (HR, 2.53 95% CI, 1.67-3.86) than in whites (HR, 1.26 95% CI, 0.83-1.93); for interactions, P = .03 and P = .02, respectively. On the other hand, there were no significant differences in the risk of MI associated with AF in older (≥75 years) vs younger (<75 years) participants (HR, 2.00 95% CI, 1.16-3.35 and HR, 1.60 95% CI, 1.11-2.30, respectively); for interaction, P = .44. CONCLUSIONS AND RELEVANCE AF is independently associated with an increased risk of incident MI, especially in women and blacks. These findings add to the growing concerns of the seriousness of AF as a public health burden: in addition to being a well-known risk factor for stroke, AF is also associated with increased risk of MI.
Atrial fibrillation (AF) is a significant health care problem for patients with obstructive sleep apnea (OSA). Continuous positive airway pressure (CPAP) as a therapy for OSA is underused, and it is ...unknown if CPAP might reduce rates of AF. We systematically reviewed the published reports on CPAP use and risk of AF. MEDLINE, EMBASE, CINAHL, Web of Science, meeting abstracts, and Cochrane databases were searched from inception to June 2015. Studies needed to report the rates of AF in participants who were and were not on CPAP. Data were extracted by 2 authors. A total of 8 studies on OSA were identified (1 randomized controlled trial) with 698 CPAP users and 549 non-CPAP users. In a random effects model, patients treated with CPAP had a 42% decreased risk of AF (pooled risk ratio, 0.58; 95% confidence interval, 0.47 to 0.70; p <0.001). There was low heterogeneity in the results ( I2 = 30%). In metaregression analysis, benefits of CPAP were stronger for younger, obese, and male patients (p <0.05). An inverse relationship between CPAP therapy and AF recurrence was observed. Results suggest that more patients with AF also should be tested for OSA.
Background
A growing body of evidence suggests that atrial fibrillation (AF) is associated with myocardial infarction (MI). However, incidence and management of MI in AF is still undefined.
Methods ...and Results
We searched MEDLINE via PubMed and Cochrane database between 1965 and 2015. All observational clinical studies and interventional trials reporting 1‐year incidence of MI in AF were included. We also discussed pathophysiological mechanisms, predictors, and therapeutic approaches to reduce the risk of MI in AF. Twenty‐one observational studies and 10 clinical trials were included. The annual rate of MI in observational studies including AF patients ranged from 0.4% to 2.5%. Higher rates of MI were reported in AF patients with stable coronary artery disease (11.5%/year), vascular disease (4.47%/year), heart failure (2.9%/year), and in those undergoing coronary artery interventions (6.3%/year). However, lower annual rates have been described in AF patients from Eastern countries (0.2–0.3%/year), and in those enrolled in clinical trials (from 0.4 to 1.3%/year).
Conclusions
AF patients had a significant residual risk of MI despite anticoagulant treatment. Coexistence of atherosclerotic risk factors and platelet activation account for the increased risk of MI in AF. Identification of high‐risk AF patients is a needed first step to develop cost‐effective approaches for prevention. A new score, the 2MACE score, has been recently developed to stratify MI risk in AF, and may help not only in allocating resources to high‐risk groups, but also in design of studies examining novel therapies for prevention of MI in AF.
Coronary heart disease (CHD) is the most common underlying risk factor for heart failure (HF); up to one-third of the patients who are hospitalized for HF each year in the United States have a ...history of myocardial infarction (MI). Although silent MI (SMI) could account for up to one-half of all MIs, only a few studies examined the relationship between SMI and risk of HF. These few studies agreed on their conclusions that SMI is associated with increased risk of HF. However, there was less agreement on the magnitude of risk and the sex differences in the association between SMI and HF, which is probably due to the heterogeneity in how these studies defined SMI. This report summarizes and discusses the current evidence linking SMI to HF, the impact of the methods by which SMI is defined on the reported relationship between SMI and HF, the potential mechanisms for such relationship, the implications of these findings, and the gaps in knowledge that need to be addressed.
Although advanced interatrial block (aIAB) is an established electrocardiographic phenotype, its prevalence, incidence, and prognostic significance in the general population are unclear. We examined ...the prevalence, incidence, and prognostic significance of aIAB in 14,625 (mean age = 54 ± 5.8 years; 26% black; 55% female) participants from the Atherosclerosis Risk in Communities (ARIC) study. aIAB was detected from digital electrocardiograms recorded during 4 study visits (1987 to 1989, 1990 to 1992, 1993 to 1995, and 1996 to 1998). Risk factors for the development of aIAB were examined using multivariable Poisson regression models with robust variance estimates. Cox regression was used to compute hazard ratios and 95% CIs for the association between aIAB, as a time-dependent variable, and atrial fibrillation (AF). AF was ascertained from study electrocardiogram data, hospital discharge records, and death certificates thorough 2010. A total of 69 participants (0.5%) had aIAB at baseline, and 193 (1.3%) developed aIAB during follow-up. The incidence for aIAB was 2.27 (95% CI 1.97 to 2.61) per 1,000 person-years. Risk factors for aIAB development included age, male gender, white race, antihypertensive medication use, low-density lipoprotein cholesterol, body mass index, and systolic blood pressure. In a Cox regression analysis adjusted for sociodemographics, cardiovascular risk factors, and potential confounders, aIAB was associated with an increased risk for AF (hazard ratio 3.09, 95% CI 2.51 to 3.79). In conclusion, aIAB is not uncommon in the general population. Risk factors for developing aIAB are similar to those for AF, and the presence of aIAB is associated with an increased risk for AF.
A risk score for atrial fibrillation (AF) has been developed by the Framingham Heart Study; however, the applicability of this risk score, derived using data from white patients, to predict new-onset ...AF in nonwhites is uncertain. Therefore, we developed a 10-year risk score for new-onset AF from risk factors commonly measured in clinical practice using 14,546 subjects from the Atherosclerosis Risk In Communities (ARIC) study, a prospective community-based cohort of blacks and whites in the United States. During 10 years of follow-up, 515 incident AF events occurred. The following variables were included in the AF risk score: age, race, height, smoking status, systolic blood pressure, hypertension medication use, precordial murmur, left ventricular hypertrophy, left atrial enlargement, diabetes, coronary heart disease, and heart failure. The area under the receiver operating characteristics curve (AUC) of a Cox regression model that included the previous variables was 0.78, suggesting moderately good discrimination. The point-based score developed from the coefficients in the Cox model had an AUC of 0.76. This clinical risk score for AF in the Atherosclerosis Risk In Communities cohort compared favorably with the Framingham Heart Study's AF (AUC 0.68), coronary heart disease (CHD) (AUC 0.63), and hard CHD (AUC 0.59) risk scores and the Atherosclerosis Risk In Communities CHD risk score (AUC 0.58). In conclusion, we have developed a risk score for AF and have shown that the different pathophysiologies of AF and CHD limit the usefulness of a CHD risk score in identifying subjects at greater risk of AF.
Objectives To define the incidence and cumulative risk of atrial fibrillation (AF) in a population-based cohort of whites and African Americans. Background African-Americans reportedly have a lower ...risk of AF than whites despite their higher exposure to AF risk factors. However, precise estimates of AF incidence in African Americans have not been previously published. Methods We studied the incidence of AF in the Atherosclerosis Risk in Communities (ARIC) study, which has followed up 15,792 men and women 45 to 65 years of age at baseline from 4 communities in the United States since 1987. Atrial fibrillation cases were identified from electrocardiograms conducted at baseline and 3 follow-up visits, and from hospitalizations and death certificates through the end of 2004. During follow-up, 1,085 new cases of AF were identified (196 in African Americans, 889 in whites). Results Crude incidence rates of AF were 6.7, 4.0, 3.9, and 3.0 per 1,000 persons per year in white men, white women, African-American men, and African-American women, respectively. Increasing age was exponentially associated with an elevated risk of AF. Compared to whites, African-Americans had a 41% (95% CI: 8%-62%) lower age- and sex-adjusted risk of being diagnosed with AF. The cumulative risk of AF at 80 years of age was 21% in white men, 17% in white women, and 11% in African-American men and women. Conclusion In this population-based cohort, African Americans presented a lower risk of AF than whites. Still, the burden of AF among the former is substantial, with 1 in 9 receiving a diagnosis of AF before 80 years of age.
Atrial fibrillation (AF) is common in patients with life-threatening cancer and those undergoing active cancer treatment. However, data from subjects with a history of non–life-threatening cancer and ...those who do not require active cancer treatment are lacking. A total of 15,428 (mean age 66 ± 8.9 years; 47% women; 45% blacks) participants from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study with baseline data on previous cancer diagnosis and AF were included. Participants with life-threatening cancer and active cancer treatment within 2 years of study enrollment were excluded. History of cancer was identified using computer-assisted telephone interviews. AF cases were identified from baseline electrocardiogram data and by a self-reported history of a previous diagnosis. Logistic regression was used to examine the cross-sectional association between cancer diagnosis and AF. A total of 2,248 (15%) participants had a diagnosis of cancer and 1,295 (8.4%) had AF. In a multivariable logistic regression model adjusted for sociodemographic characteristics (age, gender, race, education, income, and region of residence) and cardiovascular risk factors (systolic blood pressure, high-density lipoprotein cholesterol, total cholesterol, C-reactive protein, body mass index, smoking, diabetes, antihypertensive and lipid-lowering agents, left ventricular hypertrophy, and cardiovascular disease), those with cancer were more likely to have prevalent AF than those without cancer (odds ratio 1.19, 95% confidence interval 1.02 to 1.38). Subgroup analyses by age, sex, race, cardiovascular disease, and C-reactive protein yielded similar results. In conclusion, AF was more prevalent in participants with a history of non–life-threatening cancer and those who did not require active cancer treatment in REGARDS.
New Scope of the Document Although reports on cardiovascular screening efficacy have predominantly involved populations of adolescents and young adults participating in competitive athletics, the ...context of the present discussion is intentionally (and necessarily) much more expansive. ...it is underscored that the present report is not limited in scope to universal mass screening for athlete populations but importantly includes considerations for screening large, young, and truly general populations (school-aged, 12-25 years old, of both sexes) with respect to relevant logistical, ethical, legal, and societal issues (e.g., in the United States or other countries or communities of various sizes, in schools, or in regional or military populations).