@article {1247, title = {Validation of an atrial fibrillation risk algorithm in whites and African Americans.}, journal = {Arch Intern Med}, volume = {170}, year = {2010}, month = {2010 Nov 22}, pages = {1909-17}, abstract = {

BACKGROUND: We sought to validate a recently published risk algorithm for incident atrial fibrillation (AF) in independent cohorts and other racial groups.

METHODS: We evaluated the performance of a Framingham Heart Study (FHS)-derived risk algorithm modified for 5-year incidence of AF in the FHS (n = 4764 participants) and 2 geographically and racially diverse cohorts in the age range 45 to 95 years: AGES (the Age, Gene/Environment Susceptibility-Reykjavik Study) (n = 4238) and CHS (the Cardiovascular Health Study) (n = 5410, of whom 874 [16.2\%] were African Americans). The risk algorithm included age, sex, body mass index, systolic blood pressure, electrocardiographic PR interval, hypertension treatment, and heart failure.

RESULTS: We found 1359 incident AF events in 100 074 person-years of follow-up. Unadjusted 5-year event rates differed by cohort (AGES, 12.8 cases/1000 person-years; CHS whites, 22.7 cases/1000 person-years; and FHS, 4.5 cases/1000 person-years) and by race (CHS African Americans, 18.4 cases/1000 person-years). The strongest risk factors in all samples were age and heart failure. The relative risks for incident AF associated with risk factors were comparable across cohorts and race groups. After recalibration for baseline incidence and risk factor distribution, the Framingham algorithm, reported in C statistic, performed reasonably well in all samples: AGES, 0.67 (95\% confidence interval [CI], 0.64-0.71); CHS whites, 0.68 (95\% CI, 0.66-0.70); and CHS African Americans, 0.66 (95\% CI, 0.61-0.71). Risk factors combined in the algorithm explained between 47.0\% (AGES) and 63.6\% (FHS) of the population-attributable risk.

CONCLUSIONS: Risk of incident AF in community-dwelling whites and African Americans can be assessed reliably by routinely available and potentially modifiable clinical variables. Seven risk factors accounted for up to 64\% of risk.

}, keywords = {African Continental Ancestry Group, Age Factors, Aged, Aged, 80 and over, Algorithms, Atrial Fibrillation, Blood Pressure, Body Mass Index, Cohort Studies, Electrocardiography, Europe, European Continental Ancestry Group, Female, Follow-Up Studies, Heart Failure, Humans, Hypertension, Incidence, Kaplan-Meier Estimate, Male, Middle Aged, Proportional Hazards Models, Risk Factors, Sex Factors, Systole, United States}, issn = {1538-3679}, doi = {10.1001/archinternmed.2010.434}, author = {Schnabel, Renate B and Aspelund, Thor and Li, Guo and Sullivan, Lisa M and Suchy-Dicey, Astrid and Harris, Tamara B and Pencina, Michael J and D{\textquoteright}Agostino, Ralph B and Levy, Daniel and Kannel, William B and Wang, Thomas J and Kronmal, Richard A and Wolf, Philip A and Burke, Gregory L and Launer, Lenore J and Vasan, Ramachandran S and Psaty, Bruce M and Benjamin, Emelia J and Gudnason, Vilmundur and Heckbert, Susan R} } @article {6287, title = {Genome-wide association of body fat distribution in African ancestry populations suggests new loci.}, journal = {PLoS Genet}, volume = {9}, year = {2013}, month = {2013}, pages = {e1003681}, abstract = {

Central obesity, measured by waist circumference (WC) or waist-hip ratio (WHR), is a marker of body fat distribution. Although obesity disproportionately affects minority populations, few studies have conducted genome-wide association study (GWAS) of fat distribution among those of predominantly African ancestry (AA). We performed GWAS of WC and WHR, adjusted and unadjusted for BMI, in up to 33,591 and 27,350 AA individuals, respectively. We identified loci associated with fat distribution in AA individuals using meta-analyses of GWA results for WC and WHR (stage 1). Overall, 25 SNPs with single genomic control (GC)-corrected p-values<5.0 {\texttimes} 10(-6) were followed-up (stage 2) in AA with WC and with WHR. Additionally, we interrogated genomic regions of previously identified European ancestry (EA) WHR loci among AA. In joint analysis of association results including both Stage 1 and 2 cohorts, 2 SNPs demonstrated association, rs2075064 at LHX2, p = 2.24{\texttimes}10(-8) for WC-adjusted-for-BMI, and rs6931262 at RREB1, p = 2.48{\texttimes}10(-8) for WHR-adjusted-for-BMI. However, neither signal was genome-wide significant after double GC-correction (LHX2: p = 6.5 {\texttimes} 10(-8); RREB1: p = 5.7 {\texttimes} 10(-8)). Six of fourteen previously reported loci for waist in EA populations were significant (p<0.05 divided by the number of independent SNPs within the region) in AA studied here (TBX15-WARS2, GRB14, ADAMTS9, LY86, RSPO3, ITPR2-SSPN). Further, we observed associations with metabolic traits: rs13389219 at GRB14 associated with HDL-cholesterol, triglycerides, and fasting insulin, and rs13060013 at ADAMTS9 with HDL-cholesterol and fasting insulin. Finally, we observed nominal evidence for sexual dimorphism, with stronger results in AA women at the GRB14 locus (p for interaction = 0.02). In conclusion, we identified two suggestive loci associated with fat distribution in AA populations in addition to confirming 6 loci previously identified in populations of EA. These findings reinforce the concept that there are fat distribution loci that are independent of generalized adiposity.

}, keywords = {Adiposity, African Continental Ancestry Group, Body Fat Distribution, European Continental Ancestry Group, Female, Genetic Loci, Genome-Wide Association Study, Humans, Male, Obesity, Polymorphism, Single Nucleotide, Waist-Hip Ratio}, issn = {1553-7404}, doi = {10.1371/journal.pgen.1003681}, author = {Liu, Ching-Ti and Monda, Keri L and Taylor, Kira C and Lange, Leslie and Demerath, Ellen W and Palmas, Walter and Wojczynski, Mary K and Ellis, Jaclyn C and Vitolins, Mara Z and Liu, Simin and Papanicolaou, George J and Irvin, Marguerite R and Xue, Luting and Griffin, Paula J and Nalls, Michael A and Adeyemo, Adebowale and Liu, Jiankang and Li, Guo and Ruiz-Narvaez, Edward A and Chen, Wei-Min and Chen, Fang and Henderson, Brian E and Millikan, Robert C and Ambrosone, Christine B and Strom, Sara S and Guo, Xiuqing and Andrews, Jeanette S and Sun, Yan V and Mosley, Thomas H and Yanek, Lisa R and Shriner, Daniel and Haritunians, Talin and Rotter, Jerome I and Speliotes, Elizabeth K and Smith, Megan and Rosenberg, Lynn and Mychaleckyj, Josyf and Nayak, Uma and Spruill, Ida and Garvey, W Timothy and Pettaway, Curtis and Nyante, Sarah and Bandera, Elisa V and Britton, Angela F and Zonderman, Alan B and Rasmussen-Torvik, Laura J and Chen, Yii-Der Ida and Ding, Jingzhong and Lohman, Kurt and Kritchevsky, Stephen B and Zhao, Wei and Peyser, Patricia A and Kardia, Sharon L R and Kabagambe, Edmond and Broeckel, Ulrich and Chen, Guanjie and Zhou, Jie and Wassertheil-Smoller, Sylvia and Neuhouser, Marian L and Rampersaud, Evadnie and Psaty, Bruce and Kooperberg, Charles and Manson, JoAnn E and Kuller, Lewis H and Ochs-Balcom, Heather M and Johnson, Karen C and Sucheston, Lara and Ordovas, Jose M and Palmer, Julie R and Haiman, Christopher A and McKnight, Barbara and Howard, Barbara V and Becker, Diane M and Bielak, Lawrence F and Liu, Yongmei and Allison, Matthew A and Grant, Struan F A and Burke, Gregory L and Patel, Sanjay R and Schreiner, Pamela J and Borecki, Ingrid B and Evans, Michele K and Taylor, Herman and Sale, Mich{\`e}le M and Howard, Virginia and Carlson, Christopher S and Rotimi, Charles N and Cushman, Mary and Harris, Tamara B and Reiner, Alexander P and Cupples, L Adrienne and North, Kari E and Fox, Caroline S} }