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Aims Activation of the angiotensin II type 1 (AT1) receptor has been shown to mediate the structural and electrical remodelling of the atrial myocardium associated with atrial fibrillation. We hypothesized that AT1 genotypic variation is associated with atrial fibrillation or diseases predisposing to atrial fibrillation, such as hypertension, heart failure, ischaemic heart disease and myocardial infarction, in the general population. Methods We resequenced the AT1 gene in 760 individuals with atrial fibrillation and identified two nonsynonymous variants ( I103 T and A244 S), which were subsequently genotyped in the prospective Copenhagen City Heart Study ( n = 10 603) and the prospective Copenhagen General Population Study ( n = 60 647). Results Risk of atrial fibrillation for heterozygotes for AT1 genetic variants A244 S and I103 T/ A244 S vs. noncarriers was increased by 2.7-fold (95% confidence interval 1.5- to 5.1-fold) and 2.6-fold (95% confidence interval 1.6- to 4.2-fold), respectively, for men. Conclusions Heterozygosity for the nonsynonymous AT1 genetic variants A244 S and I103 T/ A244 S was associated with increased risk of atrial fibrillation in men. The AT1 recptor might be a target for the pharmaceutical industry. This finding needs to be validated in independent studies. [ABSTRACT FROM AUTHOR]

Abstract: Objective: ATP‐binding‐cassette transporter A7(ABCA7) is suggested to be involved in lipid transport as well as in phagocytosis of amyloid‐β in the brain. We tested the hypothesis that a common genetic variant in ABCA7 is associated with dementia, ischemic heart disease, ischemic cerebrovascular disease, and with lipid levels in the general population, independent of the common apolipoprotein E(APOE) genotype. Methods: For this purpose, we genotyped a common genetic variant in ABCA7, identified in genome‐wide‐association‐studies of Alzheimer's disease, in 104,258 individuals from the Danish general population, and also meta‐analyzed our results with publicly available consortia data. Results: Multifactorially adjusted hazard ratios for Alzheimer's disease were 1.07 (95% confidence interval:0.93–1.23) and 1.72 (1.24–2.40) for GA and AA versus GG genotype. Results were similar after APOE genotype adjustment and when only APOE ɛ33 carriers were studied. Including 178,304 individuals, the meta‐analyzed odds ratio for Alzheimer's disease per one allele ABCA7 rs4147929 increase was 1.15 (1.12–1.18). ABCA7 genotype was not convincingly associated with vascular dementia, ischemic heart disease, ischemic cerebrovascular disease, or with lipid levels. Including 288,563 individuals, meta‐analyzed odds ratios for ischemic heart disease per one allele ABCA7 rs4147929 increase was 1.01 (0.99–1.03). Interpretation: A common genetic variant in ABCA7 was associated with high risk of Alzheimer's disease independent of APOE genotype. The lack of association with vascular dementia, ischemic heart disease, ischemic cerebrovascular disease, and with lipid levels suggests that ABCA7 is not important for atherosclerosis. Thus, our findings support the suggested role of ABCA7 in Alzheimer's disease pathology and phagocytic clearance of amyloid‐β in the brain. [ABSTRACT FROM AUTHOR]

Objective: We used genetic variants that are robustly associated with adiposity to examine the causal association of adiposity with psychological distress. Methods: We examined the association of adiposity with psychological distress in a large (N = 53,221) general population cohort of 20- to 99-year-old adults from Copenhagen, Denmark. Psychological distress was assessed using four questions that asked about: feeling stressed; not accomplishing very much; wanting to give up; and regular use of antidepressants/sedatives. We used the genetic loci FTO rs9939609 and MC4R rs17782313 as instrumental variables for adiposity quantified by body mass index (BMI) and waist to hip ratio (WHR). Results: In conventional multivariable analyses, BMI and WHR were positively associated with distress. For example, the odds ratio of reporting not accomplishing for each additional standard deviation increase for BMI was 1.11 (95% CI: 1.09, 1.13) and for WHR was 1.10 (95% CI: 1.08, 1.13) in the fully adjusted analyses. In contrast, instrumental variable analyses showed an inverse association of adiposity on distress; corresponding odds ratio in instrumental variable analyses was 0.64 (95% CI: 0.46, 0.89) for BMI and 0.49 (95% CI: 0.25, 0.94) for WHR (P-values for difference between the two approaches both = 0.001). Conclusion: The inverse associations of adiposity and psychological distress when genetic variants are used as instrumental variables could be explained by biological pathways linking adiposity and distress. The positive associations of adiposity with distress in multivariable analyses might be explained by residual confounding or reverse causality. [ABSTRACT FROM AUTHOR]

Lawlor DA, Harbord RM, Tybjaerg-Hansen A, Palmer TM, Zacho J, Benn M, Timpson NJ, Smith GD, Nordestgaard BG (MRC Centre for Causal Analyses in Translational Epidemiology, University of Bristol, UK; The Department of Social Medicine, University of Bristol, UK; Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark; The Copenhagen General Population Study, Herlev Hospital, Copenhagen, Denmark; Copenhagen University Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark; Department of Clinical Biochemistry, Herlev Hospital, Copenhagen, Denmark) Using genetic loci to understand the relationship between adiposity and psychological distress: a Mendelian Randomization study in the Copenhagen General Population Study of 53 221 adults. J Intern Med 2011; : 525-537. We used genetic variants that are robustly associated with adiposity to examine the causal association of adiposity with psychological distress. We examined the association of adiposity with psychological distress in a large ( N = 53 221) general population cohort of 20- to 99-year-old adults from Copenhagen, Denmark. Psychological distress was assessed using four questions that asked about: feeling stressed; not accomplishing very much; wanting to give up; and regular use of antidepressants/sedatives. We used the genetic loci FTO rs9939609 and MC4R rs17782313 as instrumental variables for adiposity quantified by body mass index (BMI) and waist to hip ratio (WHR). In conventional multivariable analyses, BMI and WHR were positively associated with distress. For example, the odds ratio of reporting not accomplishing for each additional standard deviation increase for BMI was 1.11 (95% CI: 1.09, 1.13) and for WHR was 1.10 (95% CI: 1.08, 1.13) in the fully adjusted analyses. In contrast, instrumental variable analyses showed an inverse association of adiposity on distress; corresponding odds ratio in instrumental variable analyses was 0.64 (95% CI: 0.46, 0.89) for BMI and 0.49 (95% CI: 0.25, 0.94) for WHR ( P-values for difference between the two approaches both = 0.001). The inverse associations of adiposity and psychological distress when genetic variants are used as instrumental variables could be explained by biological pathways linking adiposity and distress. The positive associations of adiposity with distress in multivariable analyses might be explained by residual confounding or reverse causality. [ABSTRACT FROM AUTHOR]