@article {7601, title = {Fibroblast Growth Factor 23, Mineral Metabolism, and Adiposity in Normal Kidney Function.}, journal = {J Clin Endocrinol Metab}, volume = {102}, year = {2017}, month = {2017 Apr 01}, pages = {1387-1395}, abstract = {

Context: Obesity is associated with poor bone mineralization and quality. Fibroblast growth factor 23 (FGF23) plays an important role in skeletal physiology.

Objective: To test hypothesis that greater adiposity results in higher FGF23 levels among individuals with normal estimated glomerular filtration rate (eGFR).

Design, Setting, Participants: Cross-sectional analyses among participants with eGFR >=60 mL/min/1.73m2. We assessed the association between crude [body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR); n = 5610] and refined (abdominal adipose tissue area by computed tomography; n = 1313) measures of adiposity and FGF23 using multivariable linear regression.

Main Outcome Measure: Serum FGF23.

Results: FGF23 was higher across BMI categories (BMI <25: 37.7; BMI 25 to 29.99: 38.7; BMI 30 to 39.99: 39.8; BMI >=40: 40.9 pg/mL, unadjusted P trend < 0.0001). The association between BMI and FGF23 was independent of known confounders of FGF23 (adjusted β = +7.2\% higher FGF23 per 10 kg/m2; P < 0.0001). Similar results were observed using WC and WHR. Abdominal adipose tissue area was also independently associated with higher FGF23 (P < 0.01). Notably, the positive associations between FGF23 and adiposity were observed despite the fact that eGFR did not decline and serum phosphate levels did not increase with adiposity.

Conclusion: In a large cohort with normal kidney function, adiposity was associated with higher FGF23 levels independent of known confounders, including eGFR and phosphate. Further studies are needed to evaluate the causes of higher FGF23 in settings of greater adiposity and the potential impact on skeletal health.

}, keywords = {Adiposity, Aged, Aged, 80 and over, Cross-Sectional Studies, Female, Fibroblast Growth Factors, Glomerular Filtration Rate, Humans, Kidney, Male, Middle Aged, Minerals, Renal Insufficiency, Chronic, Risk Factors}, issn = {1945-7197}, doi = {10.1210/jc.2016-3563}, author = {Zaheer, Sarah and de Boer, Ian H and Allison, Matthew and Brown, Jenifer M and Psaty, Bruce M and Robinson-Cohen, Cassianne and Michos, Erin D and Ix, Joachim H and Kestenbaum, Bryan and Siscovick, David and Vaidya, Anand} } @article {7774, title = {Genetic Variants Associated with Circulating Fibroblast Growth Factor 23.}, journal = {J Am Soc Nephrol}, year = {2018}, month = {2018 Sep 14}, abstract = {

BACKGROUND: Fibroblast growth factor 23 (FGF23), a bone-derived hormone that regulates phosphorus and vitamin D metabolism, contributes to the pathogenesis of mineral and bone disorders in CKD and is an emerging cardiovascular risk factor. Central elements of FGF23 regulation remain incompletely understood; genetic variation may help explain interindividual differences.

METHODS: We performed a meta-analysis of genome-wide association studies of circulating FGF23 concentrations among 16,624 participants of European ancestry from seven cohort studies, excluding participants with eGFR<30 ml/min per 1.73 m to focus on FGF23 under normal conditions. We evaluated the association of single-nucleotide polymorphisms (SNPs) with natural log-transformed FGF23 concentration, adjusted for age, sex, study site, and principal components of ancestry. A second model additionally adjusted for BMI and eGFR.

RESULTS: We discovered 154 SNPs from five independent regions associated with FGF23 concentration. The SNP with the strongest association, rs17216707 (=3.0{\texttimes}10), lies upstream of , which encodes the primary catabolic enzyme for 1,25-dihydroxyvitamin D and 25-hydroxyvitamin D. Each additional copy of the T allele at this locus is associated with 5\% higher FGF23 concentration. Another locus strongly associated with variations in FGF23 concentration is rs11741640, within and upstream of (a gene involved in renal phosphate transport). Additional adjustment for BMI and eGFR did not materially alter the magnitude of these associations. Another top locus (within , the ABO blood group transferase gene) was no longer statistically significant at the genome-wide level.

CONCLUSIONS: Common genetic variants located near genes involved in vitamin D metabolism and renal phosphate transport are associated with differences in circulating FGF23 concentrations.

}, issn = {1533-3450}, doi = {10.1681/ASN.2018020192}, author = {Robinson-Cohen, Cassianne and Bartz, Traci M and Lai, Dongbing and Ikizler, T Alp and Peacock, Munro and Imel, Erik A and Michos, Erin D and Foroud, Tatiana M and {\r A}kesson, Kristina and Taylor, Kent D and Malmgren, Linnea and Matsushita, Kunihiro and Nethander, Maria and Eriksson, Joel and Ohlsson, Claes and Mellstr{\"o}m, Daniel and Wolf, Myles and Ljunggren, Osten and McGuigan, Fiona and Rotter, Jerome I and Karlsson, Magnus and Econs, Michael J and Ix, Joachim H and Lutsey, Pamela L and Psaty, Bruce M and de Boer, Ian H and Kestenbaum, Bryan R} } @article {7667, title = {Genome-wide association study in 79,366 European-ancestry individuals informs the genetic architecture of 25-hydroxyvitamin D levels.}, journal = {Nat Commun}, volume = {9}, year = {2018}, month = {2018 Jan 17}, pages = {260}, abstract = {

Vitamin D is a steroid hormone precursor that is associated with a range of human traits and diseases. Previous GWAS of serum 25-hydroxyvitamin D concentrations have identified four genome-wide significant loci (GC, NADSYN1/DHCR7, CYP2R1, CYP24A1). In this study, we expand the previous SUNLIGHT Consortium GWAS discovery sample size from 16,125 to 79,366 (all European descent). This larger GWAS yields two additional loci harboring genome-wide significant variants (P = 4.7{\texttimes}10 at rs8018720 in SEC23A, and P = 1.9{\texttimes}10 at rs10745742 in AMDHD1). The overall estimate of heritability of 25-hydroxyvitamin D serum concentrations attributable to GWAS common SNPs is 7.5\%, with statistically significant loci explaining 38\% of this total. Further investigation identifies signal enrichment in immune and hematopoietic tissues, and clustering with autoimmune diseases in cell-type-specific analysis. Larger studies are required to identify additional common SNPs, and to explore the role of rare or structural variants and gene-gene interactions in the heritability of circulating 25-hydroxyvitamin D levels.

}, issn = {2041-1723}, doi = {10.1038/s41467-017-02662-2}, author = {Jiang, Xia and O{\textquoteright}Reilly, Paul F and Aschard, Hugues and Hsu, Yi-Hsiang and Richards, J Brent and Dupuis, Jos{\'e}e and Ingelsson, Erik and Karasik, David and Pilz, Stefan and Berry, Diane and Kestenbaum, Bryan and Zheng, Jusheng and Luan, Jianan and Sofianopoulou, Eleni and Streeten, Elizabeth A and Albanes, Demetrius and Lutsey, Pamela L and Yao, Lu and Tang, Weihong and Econs, Michael J and Wallaschofski, Henri and V{\"o}lzke, Henry and Zhou, Ang and Power, Chris and McCarthy, Mark I and Michos, Erin D and Boerwinkle, Eric and Weinstein, Stephanie J and Freedman, Neal D and Huang, Wen-Yi and van Schoor, Natasja M and van der Velde, Nathalie and Groot, Lisette C P G M de and Enneman, Anke and Cupples, L Adrienne and Booth, Sarah L and Vasan, Ramachandran S and Liu, Ching-Ti and Zhou, Yanhua and Ripatti, Samuli and Ohlsson, Claes and Vandenput, Liesbeth and Lorentzon, Mattias and Eriksson, Johan G and Shea, M Kyla and Houston, Denise K and Kritchevsky, Stephen B and Liu, Yongmei and Lohman, Kurt K and Ferrucci, Luigi and Peacock, Munro and Gieger, Christian and Beekman, Marian and Slagboom, Eline and Deelen, Joris and Heemst, Diana van and Kleber, Marcus E and M{\"a}rz, Winfried and de Boer, Ian H and Wood, Alexis C and Rotter, Jerome I and Rich, Stephen S and Robinson-Cohen, Cassianne and den Heijer, Martin and Jarvelin, Marjo-Riitta and Cavadino, Alana and Joshi, Peter K and Wilson, James F and Hayward, Caroline and Lind, Lars and Micha{\"e}lsson, Karl and Trompet, Stella and Zillikens, M Carola and Uitterlinden, Andr{\'e} G and Rivadeneira, Fernando and Broer, Linda and Zgaga, Lina and Campbell, Harry and Theodoratou, Evropi and Farrington, Susan M and Timofeeva, Maria and Dunlop, Malcolm G and Valdes, Ana M and Tikkanen, Emmi and Lehtim{\"a}ki, Terho and Lyytik{\"a}inen, Leo-Pekka and K{\"a}h{\"o}nen, Mika and Raitakari, Olli T and Mikkil{\"a}, Vera and Ikram, M Arfan and Sattar, Naveed and Jukema, J Wouter and Wareham, Nicholas J and Langenberg, Claudia and Forouhi, Nita G and Gundersen, Thomas E and Khaw, Kay-Tee and Butterworth, Adam S and Danesh, John and Spector, Timothy and Wang, Thomas J and Hypp{\"o}nen, Elina and Kraft, Peter and Kiel, Douglas P} } @article {7681, title = {Trans-ethnic Evaluation Identifies Novel Low Frequency Loci Associated with 25-Hydroxyvitamin D Concentrations.}, journal = {J Clin Endocrinol Metab}, year = {2018}, month = {2018 Jan 09}, abstract = {

Context: Vitamin D inadequacy is common in the adult population of the United States. While the genetic determinants underlying vitamin D inadequacy have been studied in people of European ancestry, less is known in Hispanic or African ancestry populations.

Objective: The TRANSCEN-D (TRANS-ethniC Evaluation of vitamiN D GWAS) consortium was assembled to replicate genetic associations with 25-hydroxyvitamin D (25(OH)D) concentrations from the meta-analyses of European ancestry (SUNLIGHT) and to identify novel genetic variants related to vitamin D concentrations in African and Hispanic ancestries.

Design: Ancestry-specific (Hispanic and African) and trans-ethnic (Hispanic, African and European) meta-analyses were performed using the METAL software.

Patients or Other Participants: In total, 8,541 African-American and 3,485 Hispanic-American (from North America) participants from twelve cohorts, and 16,124 European participants from SUNLIGHT were included in the study.

Main Outcome Measure(s): Blood concentrations of 25(OH)D were measured for all participants.

Results: Ancestry-specific analyses in African and Hispanic Americans replicated SNPs in GC (2 and 4 SNPs, respectively). A potentially novel SNP (rs79666294) near the KIF4B gene was identified in the African-American cohort. Trans-ethnic evaluation replicated GC and DHCR7 region SNPs. Additionally, the trans-ethnic analyses revealed novel SNPs rs719700 and rs1410656 near the ANO6/ARID2 and HTR2A genes, respectively.

Conclusions: Ancestry-specific and trans-ethnic GWAS of 25(OH)D confirmed findings in GC and DHCR7 for African and Hispanic American samples and revealed novel findings near KIF4B, ANO6/ARID2, and HTR2A. The biological mechanisms that link these regions with 25(OH)D metabolism require further investigation.

}, issn = {1945-7197}, doi = {10.1210/jc.2017-01802}, author = {Hong, Jaeyoung and Hatchell, Kathryn E and Bradfield, Jonathan P and Andrew, Bjonnes and Alessandra, Chesi and Chao-Qiang, Lai and Langefeld, Carl D and Lu, Lingyi and Lu, Yingchang and Lutsey, Pamela L and Musani, Solomon K and Nalls, Mike A and Robinson-Cohen, Cassianne and Roizen, Jeffery D and Saxena, Richa and Tucker, Katherine L and Ziegler, Julie T and Arking, Dan E and Bis, Joshua C and Boerwinkle, Eric and Bottinger, Erwin P and Bowden, Donald W and Gilsanz, Vincente and Houston, Denise K and Kalkwarf, Heidi J and Kelly, Andrea and Lappe, Joan M and Liu, Yongmei and Michos, Erin D and Oberfield, Sharon E and Palmer, Nicholette D and Rotter, Jerome I and Sapkota, Bishwa and Shepherd, John A and Wilson, James G and Basu, Saonli and de Boer, Ian H and Divers, Jasmin and Freedman, Barry I and Grant, Struan F A and Hakanarson, Hakon and Harris, Tamara B and Kestenbaum, Bryan R and Kritchevsky, Stephen B and Loos, Ruth J F and Norris, Jill M and Norwood, Arnita F and Ordovas, Jose M and Pankow, James S and Psaty, Bruce M and Sanhgera, Dharambir K and Wagenknecht, Lynne E and Zemel, Babette S and Meigs, James and Dupuis, Jos{\'e}e and Florez, Jose C and Wang, Thomas and Liu, Ching-Ti and Engelman, Corinne D and Billings, Liana K} } @article {8788, title = {Performance of the American Heart Association/American College of Cardiology Pooled Cohort Equations to Estimate Atherosclerotic Cardiovascular Disease Risk by Self-reported Physical Activity Levels.}, journal = {JAMA Cardiol}, volume = {6}, year = {2021}, month = {2021 Jun 01}, pages = {690-696}, abstract = {

Importance: The American Heart Association/American College of Cardiology pooled cohort equations (PCEs) are used for predicting 10-year atherosclerotic cardiovascular disease (ASCVD) risk. Pooled cohort equation risk prediction capabilities across self-reported leisure-time physical activity (LTPA) levels and the change in model performance with addition of LTPA to the PCE are unclear.

Objective: To evaluate PCE risk prediction performance across self-reported LTPA levels and the change in model performance by adding LTPA to the existing PCE model.

Design, Setting, and Participants: Individual-level pooling of data from 3 longitudinal cohort studies-Atherosclerosis Risk in Communities, Multi-Ethnic Study of Atherosclerosis, and Cardiovascular Health Study-was performed. A total of 18 824 participants were stratified into 4 groups based on self-reported LTPA levels: inactive (0 metabolic equivalent of task [MET]-min/wk), less than guideline-recommended (<500 MET-min/wk), guideline-recommended (500-1000 MET-min/week), and greater than guideline-recommended (>1000 MET-min/wk). Pooled cohort equation risk discrimination was studied using the C statistic and reclassification capabilities were studied using the Greenwood Nam-D{\textquoteright}Agostino χ2 goodness-of-fit test. Change in risk discrimination and reclassification on adding LTPA to PCEs was evaluated using change in C statistic, integrated discrimination index, and categorical net reclassification index.

Main Outcomes and Measures: Adjudicated ASCVD events during 10-year follow-up.

Results: Among 18 824 participants studied, 10 302 were women (54.7\%); mean (SD) age was 57.6 (8.2) years. A total of 5868 participants (31.2\%) were inactive, 3849 (20.4\%) had less than guideline-recommended LTPA, 3372 (17.9\%) had guideline-recommended LTPA, and 5735 (30.5\%) had greater than guideline-recommended LTPA level. Higher LTPA levels were associated with a lower risk of ASCVD after adjustment for risk factors (hazard ratio [HR] per 1-SD higher LTPA, 0.91; 95\% CI, 0.86-0.96). Across LTPA groups, PCE risk discrimination (C statistic, 0.76-0.78) and risk calibration (all χ2 P > .10) was similar. Addition of LTPA to the PCE model resulted in no significant change in the C statistic (0.0005; 95\% CI, -0.0004 to 0.0015; P = .28) and categorical net reclassification index (-0.003; 95\% CI, -0.010 to 0.010; P = .95), but a minimal improvement in the integrated discrimination index (0.0008; 95\% CI, 0.0002-0.0013; P = .005) was observed. Similar results were noted when cohort-specific coefficients were used for creating the baseline model.

Conclusions and Relevance: Higher self-reported LTPA levels appear to be associated with lower ASCVD risk and increasing LTPA promotes cardiovascular wellness. These findings suggest the American Heart Association/American College of Cardiology PCEs are accurate at estimating the probability of 10-year ASCVD risk regardless of LTPA level. The addition of self-reported LTPA to PCEs does not appear to be associated with improvement in risk prediction model performance.

}, issn = {2380-6591}, doi = {10.1001/jamacardio.2021.0948}, author = {Pandey, Ambarish and Mehta, Anurag and Paluch, Amanda and Ning, Hongyan and Carnethon, Mercedes R and Allen, Norrina B and Michos, Erin D and Berry, Jarett D and Lloyd-Jones, Donald M and Wilkins, John T} }