@article {5996, title = {Fibroblast growth factor 23, bone mineral density, and risk of hip fracture among older adults: the cardiovascular health study.}, journal = {J Clin Endocrinol Metab}, volume = {98}, year = {2013}, month = {2013 Aug}, pages = {3323-31}, abstract = {

CONTEXT: Fibroblast growth factor 23 (FGF23) is a phosphaturic hormone that also inhibits calcitriol synthesis.

OBJECTIVE: Our objective was to evaluate the relationships of plasma FGF23 concentrations with bone mineral density (BMD) and hip fracture in community-dwelling older adults.

DESIGN AND SETTING: Linear regression and Cox proportional hazard models were used to examine the associations of plasma FGF23 concentrations with BMD and incident hip fracture, respectively. Analyses were also stratified by chronic kidney disease.

PARTICIPANTS: Participants included 2008 women and 1329 men >=65 years from the 1996 to 1997 Cardiovascular Health Study visit.

MAIN OUTCOME MEASURES: Dual x-ray absorptiometry measured total hip (TH) and lumbar spine (LS) BMD in 1291 participants. Hip fracture incidence was assessed prospectively through June 30, 2008 by hospitalization records in all participants.

RESULTS: Women had higher plasma FGF23 concentrations than men (75 [56-107] vs 66 [interquartile range = 52-92] relative units/mL; P < .001). After adjustment, higher FGF23 concentrations were associated with greater total hip and lumbar spine BMD in men only (β per doubling of FGF23 = 0.02, with 95\% confidence interval [CI] = 0.001-0.04 g/cm(2), and 0.03 with 95\% CI = 0.01-0.06 g/cm(2)). During 9.6 {\textpm} 5.1-11.0 years of follow-up, 328 hip fractures occurred. Higher FGF23 concentrations were not associated with hip fracture risk in women or men (adjusted hazard ratio = 0.95, with 95\% CI = 0.78-1.15, and 1.09 with 95\% CI = 0.82-1.46 per doubling of FGF23). Results did not differ by chronic kidney disease status (P > .4 for interactions).

CONCLUSIONS: In this large prospective cohort of community-dwelling older adults, higher FGF23 concentrations were weakly associated with greater lumbar spine and total hip BMD but not with hip fracture risk.

}, keywords = {Aged, Aged, 80 and over, Bone Density, Female, Fibroblast Growth Factors, Hip Fractures, Humans, Longitudinal Studies, Male, Middle Aged, Prospective Studies, Risk, Spinal Fractures}, issn = {1945-7197}, doi = {10.1210/jc.2013-1152}, author = {Jovanovich, Anna and B{\r u}zkov{\'a}, Petra and Chonchol, Michel and Robbins, John and Fink, Howard A and de Boer, Ian H and Kestenbaum, Bryan and Katz, Ronit and Carbone, Laura and Lee, Jennifer and Laughlin, Gail A and Mukamal, Kenneth J and Fried, Linda F and Shlipak, Michael G and Ix, Joachim H} } @article {7379, title = {Fibroblast growth factor 23, left ventricular mass, and left ventricular hypertrophy in community-dwelling older adults.}, journal = {Atherosclerosis}, volume = {231}, year = {2013}, month = {2013 Nov}, pages = {114-9}, abstract = {

OBJECTIVES: In chronic kidney disease (CKD), high FGF23 concentrations are associated with left ventricular hypertrophy (LVH), cardiovascular events, and death. The associations of FGF23 with left ventricular mass (LVM) and LVH in the general population and the influence of CKD remains uncertain.

METHODS: C-terminal plasma FGF23 concentrations were measured, and LVM and LVH evaluated by echocardiogram among 2255 individuals >=65 years in the Cardiovascular Health Study. Linear regression analysis adjusting for demographics, cardiovascular, and kidney related risk factors examined the associations of FGF23 concentrations with LVM. Analyses were stratified by CKD status and adjusted linear and logistic regression analysis explored the associations of FGF23 with LVM and LVH.

RESULTS: Among the entire cohort, higher FGF23 concentrations were associated with greater LVM in adjusted analyses (β = 6.71 [95\% CI 4.35-9.01] g per doubling of FGF23). 32\% (n = 624) had CKD (eGFR <60 mL/min/1.73 m(2) and/or urine albumin-to-creatinine ratio >30 mg/g). Associations were stronger among participants with CKD (p interaction = 0.006): LVM β = 9.71 [95\% CI 5.86-13.56] g per doubling of FGF23 compared to those without CKD (β = 3.44 [95\% CI 0.77, 6.11] g per doubling of FGF23). While there was no significant interaction between FGF23 and CKD for LVH (p interaction = 0.25), the OR (1.46 95\% CI [1.20-1.77]) in the CKD group was statistically significant and of larger magnitude than the OR for in the no CKD group (1.12 [95\% CI 0.97-1.48]).

CONCLUSION: In a large cohort of older community-dwelling adults, higher FGF23 concentrations were associated with greater LVM and LVH with stronger relationships in participants with CKD.

}, keywords = {Aged, Female, Fibroblast Growth Factors, Heart Ventricles, Humans, Hypertrophy, Left Ventricular, Longitudinal Studies, Male, Renal Insufficiency, Chronic, Risk Factors, Ultrasonography}, issn = {1879-1484}, doi = {10.1016/j.atherosclerosis.2013.09.002}, author = {Jovanovich, Anna and Ix, Joachim H and Gottdiener, John and McFann, Kim and Katz, Ronit and Kestenbaum, Bryan and de Boer, Ian H and Sarnak, Mark and Shlipak, Michael G and Mukamal, Kenneth J and Siscovick, David and Chonchol, Michel} }