@article {6853, title = {Fetuin-A and risk of coronary heart disease: A Mendelian randomization analysis and a pooled analysis of AHSG genetic variants in 7 prospective studies.}, journal = {Atherosclerosis}, volume = {243}, year = {2015}, month = {2015 Nov}, pages = {44-52}, abstract = {

BACKGROUND AND AIMS: Fetuin-A has a plausible role in the inhibition of arterial calcification, but its association with risk of coronary heart disease (CHD) in the general population is unclear. We used two common genetic variants in the fetuin-A gene (AHSG) that are strongly associated with circulating fetuin-A levels to investigate the associations with risk of CHD and subclinical cardiovascular measures (intima-media thickness, ankle-arm index, and coronary artery calcification).

METHODS: Genetic variation and fetuin-A levels were assessed in 3299 community-living individuals (2733 Caucasians and 566 African Americans) 65 years of age or older, free of previous cardiovascular disease, who participated in the Cardiovascular Health Study (CHS) in 1992-1993.

RESULTS: Among Caucasians, both rs2248690 and rs4917 were associated with 12\% lower fetuin-A concentrations per minor allele (P~<~0.0001). The hazard ratios (HRs) per minor allele for incident CHD were 1.12 (95\% CI: 1.00-1.26) for rs2248690 and 1.02 (0.91-1.14) for rs4917. Using both genotypes as an instrumental variable for measured fetuin-A, the HRs for one standard deviation increase in genetically determined fetuin-A levels on CHD risk were 0.84 (95\% CI: 0.70-1.00) for rs2248690 and 0.97 (95\% CI: 0.82-1.14) for rs4917, respectively. However, in CHS neither of the genotypes were associated with subclinical cardiovascular measures and when CHS data were meta-analyzed with data from six other prospective studies (totaling 26,702 Caucasian participants and 3295 CHD cases), the meta-analyzed HRs for incident CHD were 1.12 (0.93-1.34) and 1.06 (0.93-1.20) for rs2248690 and rs4917, respectively (p heterogeneity 0.005 and 0.0048).

CONCLUSION: Common variants in the AHSG gene are strongly associated with fetuin-A levels, but their concurrent association with CHD risk in current prospective studies is inconsistent. Further investigation in studies with measured fetuin-A and AHSG variants is needed to clarify the potential causal association of fetuin-A with CHD risk.

}, keywords = {Aged, Aged, 80 and over, alpha-2-HS-Glycoprotein, Carotid Intima-Media Thickness, Coronary Vessels, Female, Genetic Variation, Genotype, Heart Diseases, Humans, Insulin Resistance, Longitudinal Studies, Male, Mendelian Randomization Analysis, Polymorphism, Single Nucleotide, Prospective Studies, Risk Factors, Vascular Calcification}, issn = {1879-1484}, doi = {10.1016/j.atherosclerosis.2015.08.031}, author = {Laugsand, Lars E and Ix, Joachim H and Bartz, Traci M and Djouss{\'e}, Luc and Kizer, Jorge R and Tracy, Russell P and Dehghan, Abbas and Rexrode, Kathryn and Lopez, Oscar L and Rimm, Eric B and Siscovick, David S and O{\textquoteright}Donnell, Christopher J and Newman, Anne and Mukamal, Kenneth J and Jensen, Majken K} } @article {9001, title = {Epigenetic Age and the Risk of Incident Atrial Fibrillation.}, journal = {Circulation}, volume = {144}, year = {2021}, month = {2021 12 14}, pages = {1899-1911}, abstract = {

BACKGROUND: The most prominent risk factor for atrial fibrillation (AF) is chronological age; however, underlying mechanisms are unexplained. Algorithms using epigenetic modifications to the human genome effectively predict chronological age. Chronological and epigenetic predicted ages may diverge in a phenomenon referred to as epigenetic age acceleration (EAA), which may reflect accelerated biological aging. We sought to evaluate for associations between epigenetic age measures and incident AF.

METHODS: Measures for 4 epigenetic clocks (Horvath, Hannum, DNA methylation [DNAm] PhenoAge, and DNAm GrimAge) and an epigenetic predictor of PAI-1 (plasminogen activator inhibitor-1) levels (ie, DNAm PAI-1) were determined for study participants from 3 population-based cohort studies. Cox models evaluated for associations with incident AF and results were combined via random-effects meta-analyses. Two-sample summary-level Mendelian randomization analyses evaluated for associations between genetic instruments of the EAA measures and AF.

RESULTS: Among 5600 participants (mean age, 65.5 years; female, 60.1\%; Black, 50.7\%), there were 905 incident AF cases during a mean follow-up of 12.9 years. Unadjusted analyses revealed all 4 epigenetic clocks and the DNAm PAI-1 predictor were associated with statistically significant higher hazards of incident AF, though the magnitudes of their point estimates were smaller relative to the associations observed for chronological age. The pooled EAA estimates for each epigenetic measure, with the exception of Horvath EAA, were associated with incident AF in models adjusted for chronological age, race, sex, and smoking variables. After multivariable adjustment for additional known AF risk factors that could also potentially function as mediators, pooled EAA measures for 2 clocks remained statistically significant. Five-year increases in EAA measures for DNAm GrimAge and DNAm PhenoAge were associated with 19\% (adjusted hazard ratio [HR], 1.19 [95\% CI, 1.09-1.31]; <0.01) and 15\% (adjusted HR, 1.15 [95\% CI, 1.05-1.25]; <0.01) higher hazards of incident AF, respectively. Mendelian randomization analyses for the 5 EAA measures did not reveal statistically significant associations with AF.

CONCLUSIONS: Our study identified adjusted associations between EAA measures and incident AF, suggesting that biological aging plays an important role independent of chronological age, though a potential underlying causal relationship remains unclear. These aging processes may be modifiable and not constrained by the immutable factor of time.

}, keywords = {Aged, Aging, Atrial Fibrillation, DNA Methylation, Epigenesis, Genetic, Epigenomics, Female, Follow-Up Studies, Humans, Incidence, Male, Mendelian Randomization Analysis, Middle Aged, Models, Cardiovascular, Models, Genetic}, issn = {1524-4539}, doi = {10.1161/CIRCULATIONAHA.121.056456}, author = {Roberts, Jason D and Vittinghoff, Eric and Lu, Ake T and Alonso, Alvaro and Wang, Biqi and Sitlani, Colleen M and Mohammadi-Shemirani, Pedrum and Fornage, Myriam and Kornej, Jelena and Brody, Jennifer A and Arking, Dan E and Lin, Honghuang and Heckbert, Susan R and Prokic, Ivana and Ghanbari, Mohsen and Skanes, Allan C and Bartz, Traci M and Perez, Marco V and Taylor, Kent D and Lubitz, Steven A and Ellinor, Patrick T and Lunetta, Kathryn L and Pankow, James S and Par{\'e}, Guillaume and Sotoodehnia, Nona and Benjamin, Emelia J and Horvath, Steve and Marcus, Gregory M} }