Serum fibroblast growth factor-23 concentration in dogs with myxomatous mitral valve disease
Naoki Iwasa, Mamu Shimizu, Tomoko Okamoto, Hiroto kosuga, Nayu Morikita, Mifumi Kawabe, Munetaka Iwata, Kazuhiro Watanabe, Yui Kobatake, Satoshi Takashima, Naohito NishiiAbstract
Background
Circulating fibroblast growth factor-23 (FGF-23) is primarily a kidney-related biomarker, but also may be influenced by cardiovascular remodeling and hemodynamic load.
Hypothesis/Objectives
Verify whether serum FGF-23 concentration increases with myxomatous mitral valve disease (MMVD) severity.
Animals
Forty-two client-owned dogs with MMVD without overt kidney disease.
Methods
Retrospective cross-sectional study to evaluate serum FGF-23, N-terminal pro-B-type natriuretic peptide (NT-proBNP), atrial natriuretic peptide (ANP), blood urea nitrogen (BUN), creatinine (Cr), and symmetric dimethylarginine (SDMA) concentrations. Imaging variables included vertebral heart score (VHS), vertebral left atrial size (VLAS), left atrial-to-aortic root ratio (LA/Ao), normalized left-ventricular internal diameter in diastole (LVIDDN), and diastolic transmitral E-wave velocity (E-vel). Differences among American College of Veterinary Internal Medicine stages were analyzed using the Kruskal–Wallis test with Bonferroni-adjusted pairwise comparisons. Correlations were analyzed using Spearman’s correlation. Multivariable linear regression analysis was performed to identify factors associated with serum FGF-23 concentration.
Results
Dogs with ACVIM stages C and D had higher serum FGF-23 concentrations than those with stages B1 and B2 (P < .05). Serum FGF-23 concentrations were positively correlated with VLAS (rs = 0.500, P < .01), ANP (rs = 0.455, P < .01), LA/Ao (rs = 0.384, P < .05), E-vel (rs = 0.372, P < .05), and NT-proBNP (rs = 0.366, P < .05). ACVIM stage was significantly associated with serum FGF-23 concentration after adjustment for serum Cr concentration and loop diuretic use.
Conclusions and clinical importance
The potential influence of MMVD should be considered when interpreting increased circulating FGF-23 concentrations in dogs with MMVD.