Neil A. Zakai

Population Approaches to Improve Diet, Physical Activity, and Smoking Habits A Scientific Statement From the American Heart Association

Background— Poor lifestyle behaviors, including suboptimal diet, physical inactivity, and tobacco use, are leading causes of preventable diseases globally. Although even modest population shifts in risk substantially alter health outcomes, the optimal population-level approaches to improve lifestyle are not well established. Methods and Results— For this American Heart Association scientific statement, the writing group systematically reviewed and graded the current scientific evidence for effective population approaches to improve dietary habits, increase physical activity, and reduce tobacco use. Strategies were considered in 6 broad domains: (1) Media and educational campaigns; (2) labeling and consumer information; (3) taxation, subsidies, and other economic incentives; (4) school and workplace approaches; (5) local environmental changes; and (6) direct restrictions and mandates. The writing group also reviewed the potential contributions of healthcare systems and surveillance systems to behavior change efforts. Several specific population interventions that achieved a Class I or IIa recommendation with grade A or B evidence were identified, providing a set of specific evidence-based strategies that deserve close attention and prioritization for wider implementation. Effective interventions included specific approaches in all 6 domains evaluated for improving diet, increasing activity, and reducing tobacco use. The writing group also identified several specific interventions in each of these domains for which current evidence was less robust, as well as other inconsistencies and evidence gaps, informing the need for further rigorous and interdisciplinary approaches to evaluate population programs and policies. Conclusions— This systematic review identified and graded the evidence for a range of population-based strategies to promote lifestyle change. The findings provide a framework for policy makers, advocacy groups, researchers, clinicians, communities, and other stakeholders to understand and implement the most effective approaches. New strategic initiatives and partnerships are needed to translate this evidence into action.

Detection of Chronic Kidney Disease With Creatinine, Cystatin C, and Urine Albumin-to-Creatinine Ratio and Association With Progression to End-Stage Renal Disease and Mortality

CONTEXT A triple-marker approach for chronic kidney disease (CKD) evaluation has not been well studied. OBJECTIVE To evaluate whether combining creatinine, cystatin C, and urine albumin-to-creatinine ratio (ACR) would improve identification of risks associated with CKD compared with creatinine alone. DESIGN, SETTING, AND PARTICIPANTS Prospective cohort study involving 26,643 US adults enrolled in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study from January 2003 to June 2010. Participants were categorized into 8 groups defined by estimated glomerular filtration rate (GFR) determined by creatinine and by cystatin C of either <60 or ≥60 mL/min/1.73 m(2) and ACR of either <30 or ≥30 mg/g. MAIN OUTCOME MEASURES All-cause mortality and incident end-stage renal disease with median follow-up of 4.6 years. RESULTS Participants had a mean age of 65 years, 40% were black, and 54% were women. Of 26,643 participants, 1940 died and 177 developed end-stage renal disease. Among participants without CKD defined by creatinine, 24% did not have CKD by either ACR or cystatin C. Compared with those with CKD defined by creatinine alone, the hazard ratio for death in multivariable-adjusted models was 3.3 (95% confidence interval [CI], 2.0-5.6) for participants with CKD defined by creatinine and ACR; 3.2 (95% CI, 2.2-4.7) for those with CKD defined by creatinine and cystatin C, and 5.6 (95% CI, 3.9-8.2) for those with CKD defined by all biomarkers. Among participants without CKD defined by creatinine, 3863 (16%) had CKD detected by ACR or cystatin C. Compared with participants who did not have CKD by any measure, the HRs for mortality were 1.7 (95% CI, 1.4-1.9) for participants with CKD defined by ACR alone, 2.2 (95% CI, 1.9-2.7) for participants with CKD defined by cystatin C alone, and 3.0 (95% CI, 2.4-3.7) for participants with CKD defined by both measures. Risk of incident end-stage renal disease was higher among those with CKD defined by all markers (34.1 per 1000 person-years; 95% CI, 28.7-40.5 vs 0.33 per 1000 person-years; 95% CI, 0.05-2.3) for those with CKD defined by creatinine alone. The second highest end-stage renal disease rate was among persons missed by the creatinine measure but detected by both ACR and cystatin C (rate per 1000 person-years, 6.4; 95% CI, 3.6-11.3). Net reclassification improvement for death was 13.3% (P < .001) and for end-stage renal disease was 6.4% (P < .001) after adding estimated GFR cystatin C in fully adjusted models with estimated GFR creatinine and ACR. CONCLUSION Adding cystatin C to the combination of creatinine and ACR measures improved the predictive accuracy for all-cause mortality and end-stage renal disease.

Multiple loci influence erythrocyte phenotypes in the CHARGE Consortium

Measurements of erythrocytes within the blood are important clinical traits and can indicate various hematological disorders. We report here genome-wide association studies (GWAS) for six erythrocyte traits, including hemoglobin concentration (Hb), hematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and red blood cell count (RBC). We performed an initial GWAS in cohorts of the CHARGE Consortium totaling 24,167 individuals of European ancestry and replication in additional independent cohorts of the HaemGen Consortium totaling 9,456 individuals. We identified 23 loci significantly associated with these traits in a meta-analysis of the discovery and replication cohorts (combined P values ranging from 5 × 10−8 to 7 × 10−86). Our findings include loci previously associated with these traits (HBS1L-MYB, HFE, TMPRSS6, TFR2, SPTA1) as well as new associations (EPO, TFRC, SH2B3 and 15 other loci). This study has identified new determinants of erythrocyte traits, offering insight into common variants underlying variation in erythrocyte measures.

AHA Scientific Statement Population Approaches to Improve Diet, Physical Activity, and Smoking Habits A Scientific Statement From the American Heart Association

Background— Poor lifestyle behaviors, including suboptimal diet, physical inactivity, and tobacco use, are leading causes of preventable diseases globally. Although even modest population shifts in risk substantially alter health outcomes, the optimal population-level approaches to improve lifestyle are not well established. Methods and Results— For this American Heart Association scientific statement, the writing group systematically reviewed and graded the current scientific evidence for effective population approaches to improve dietary habits, increase physical activity, and reduce tobacco use. Strategies were considered in 6 broad domains: (1) Media and educational campaigns; (2) labeling and consumer information; (3) taxation, subsidies, and other economic incentives; (4) school and workplace approaches; (5) local environmental changes; and (6) direct restrictions and mandates. The writing group also reviewed the potential contributions of healthcare systems and surveillance systems to behavior change efforts. Several specific population interventions that achieved a Class I or IIa recommendation with grade A or B evidence were identified, providing a set of specific evidence-based strategies that deserve close attention and prioritization for wider implementation. Effective interventions included specific approaches in all 6 domains evaluated for improving diet, increasing activity, and reducing tobacco use. The writing group also identified several specific interventions in each of these domains for which current evidence was less robust, as well as other inconsistencies and evidence gaps, informing the need for further rigorous and interdisciplinary approaches to evaluate population programs and policies. Conclusions— This systematic review identified and graded the evidence for a range of population-based strategies to promote lifestyle change. The findings provide a framework for policy makers, advocacy groups, researchers, clinicians, communities, and other stakeholders to understand and implement the most effective approaches. New strategic initiatives and partnerships are needed to translate this evidence into action.

Androgen-Deprivation Therapy in Prostate Cancer and Cardiovascular Risk: A Science Advisory From the American Heart Association, American Cancer Society, and American Urological Association Endorsed by the American Society for Radiation Oncology

Androgen-deprivation therapy (ADT) is a widely used treatment for prostate cancer. Recently, several studies have reported an association between ADT and an increased risk of cardiovascular events, including myocardial infarction and cardiovascular mortality.1-5 These reports have led to increased interest and discussion regarding the metabolic effects of ADT and its possible association with increased cardiovascular risk. In addition, likely as a result of these reports, internists, endocrinologists, and cardiologists are now being consulted regarding the evaluation and management of patients in whom ADT is being initiated. Most of these physicians are not aware of the possible effects of ADT on cardiovascular risk factors or the issues regarding ADT and cardiovascular disease. Therefore, this multidisciplinary writing group has been commissioned to review and summarize the metabolic effects of ADT, to evaluate the data regarding a possible relation between ADT and cardiovascular events in patients with prostate cancer, and to generate suggestions regarding the evaluation and management of patients, both with and without known cardiac disease, in whom ADT is being initiated (Table 1). TABLE 1 Prospective Studies of the Effects of ADT on Cardiac Risk Factors ADT was first used in prostate cancer for patients with overt metastatic disease,7 and it remains the mainstay of therapy for this group. ADT combined with external-beam radiation therapy is a standard of care in the treatment of men with high-risk prostate cancer, on the basis of evidence that shows a survival benefit in multiple randomized controlled trials.8-13 However, ADT is also often used for other prostate cancer states (eg, for prostate volume reduction in men planning to undergo definitive local therapy with brachytherapy, or in the case of rising prostate-specific antigen after definitive local treatment),14,15 and in these cases, its role in prolonging survival is less certain.

Atrial Fibrillation and the Risk of Myocardial Infarction

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.

Risk factors for venous thrombosis in medical inpatients: validation of a thrombosis risk score

Summary.  Background/objectives: The occurrence of and risk factors for venous thrombosis (VT) complicating hospital admission in unselected medical inpatients have not been widely studied. Patients and methods: In a 400‐bed teaching hospital we identified all cases of VT complicating hospital admission between September 2000 and September 2002 using discharge codes and chart review. Controls were randomly selected adult inpatients frequency matched to cases for medical service. Results: The incidence of VT complicating hospital admission was 7.6 per 1000 admissions. On average, VT was diagnosed on the fifth hospital day. The median age of the 65 cases and 123 controls was 68 years and 45% were men. Cases had a 4‐fold higher death rate than controls [95% confidence interval (CI) 1.9, 8.8]. At admission, trauma within 3 months, leg edema, pneumonia, platelet count > 350 × 103 mm−3 and certain cancers were associated with risk of VT. Age, body mass index, and acute myocardial infarction were not associated with VT risk. One of three published VT risk models was able to risk stratify patients and was associated with a 2.6‐fold increased risk of VT (95% CI 1.3, 5.5). Use of VT prophylaxis did not differ in cases and controls; prophylaxis was used < 1/3 of hospital days in 52% of patients. Conclusions: VT was common among medical inpatients. Of the risk factors identified, elevated platelet count has not been previously reported. Only one of three published risk scores was associated with risk of inpatient VT. Future study should improve upon risk prediction models for in‐hospital VT among medical patients.

ABO blood group, other risk factors and incidence of venous thromboembolism: the Longitudinal Investigation of Thromboembolism Etiology (LITE)

Summary.  Background: Numerous case–control studies have reported higher prevalence of non‐O blood type among venous thromboembolism (VTE) patients than controls, but potential mechanisms or effect modifiers for the association are not fully established. Patients/methods: Using a nested case–control design combining the Atherosclerosis Risk in Communities and the Cardiovascular Health Study cohort, ABO blood type and other VTE risk factors were measured on pre‐event blood samples of 492 participants who subsequently developed VTE and 1008 participants who remained free of VTE. Results: A total of 64.4% of cases and 52.5% of controls had non‐O blood type. Among controls, mean values of factor VIIIc (FVIIIc) and von Willebrand factor among the non‐O blood type group were higher than among the O group. Compared with O blood type, the age‐adjusted odds ratio (OR) of VTE for non‐O blood type was 1.64 (95% CI, 1.32–2.05) and was similar for the two parent studies and race groups. Further adjustment for sex, race, body mass index, diabetes mellitus and FVIIIc reduced the OR: 1.31 (95% CI, 1.02–1.68). Factor V Leiden (FV Leiden) appeared to modify the non‐O blood type association with VTE in a supra‐additive fashion, with an age‐, sex‐ and race‐adjusted OR of 6.77 (95% CI, 3.65–12.6) for having both risk factors. Conclusions: Non‐O blood type was independently associated with risk of VTE, and added to the risk associated with FV Leiden.

Multiple Loci Are Associated with White Blood Cell Phenotypes

White blood cell (WBC) count is a common clinical measure from complete blood count assays, and it varies widely among healthy individuals. Total WBC count and its constituent subtypes have been shown to be moderately heritable, with the heritability estimates varying across cell types. We studied 19,509 subjects from seven cohorts in a discovery analysis, and 11,823 subjects from ten cohorts for replication analyses, to determine genetic factors influencing variability within the normal hematological range for total WBC count and five WBC subtype measures. Cohort specific data was supplied by the CHARGE, HeamGen, and INGI consortia, as well as independent collaborative studies. We identified and replicated ten associations with total WBC count and five WBC subtypes at seven different genomic loci (total WBC count—6p21 in the HLA region, 17q21 near ORMDL3, and CSF3; neutrophil count—17q21; basophil count- 3p21 near RPN1 and C3orf27; lymphocyte count—6p21, 19p13 at EPS15L1; monocyte count—2q31 at ITGA4, 3q21, 8q24 an intergenic region, 9q31 near EDG2), including three previously reported associations and seven novel associations. To investigate functional relationships among variants contributing to variability in the six WBC traits, we utilized gene expression- and pathways-based analyses. We implemented gene-clustering algorithms to evaluate functional connectivity among implicated loci and showed functional relationships across cell types. Gene expression data from whole blood was utilized to show that significant biological consequences can be extracted from our genome-wide analyses, with effect estimates for significant loci from the meta-analyses being highly corellated with the proximal gene expression. In addition, collaborative efforts between the groups contributing to this study and related studies conducted by the COGENT and RIKEN groups allowed for the examination of effect homogeneity for genome-wide significant associations across populations of diverse ancestral backgrounds.

Racial differences in venous thromboembolism

Summary.  The incidence of venous thrombosis (VTE) varies by race, with African‐Americans having over 5‐fold greater incidence than Asian‐ancestry populations, and an intermediate risk for European and Hispanic populations. Known racial differences in genetic polymorphisms associated with thrombosis do not account for this gradient of risk, nor do known racial variations in environmental risk factors. Data on the incidence of and risk factors for VTE outside of Europe and North America and in non‐European ancestry populations are sparse. Common genetic polymorphisms in European‐Ancestry populations, such as factor V Leiden and prothrombin G20210A, and environmental risk factors, such as obesity, may account for some of the increased risk in European populations, and high factor VIII, high von Willebrand factor and low protein C levels and increased prevalence of obesity may explain some of the increased risk in African‐Americans. The low rates in Asian populations may be partially explained by low clinical suspicion in a perceived low‐risk population and lack of access to healthcare in other populations. As risk factors for thrombosis, such as surgery and treatment for cancer, are applicable to more people, as obesity increases in prevalence in the developing world, and as surveillance systems for VTE improve, VTE may increase in previously low‐risk populations. While differences in VTE by race due to genetic predisposition will probably always be present, understanding the reasons for racial differences in VTE will help providers develop strategies to minimize VTE in all populations.