Introduction:
Fibroblast growth factor 23 (FGF23), an endocrine hormone, induced left ventricular (LV) hypertrophy through direct action in experimental animal models. The association of FGF23 with echocardiographic measures in humans is relatively uncharacterized.
Hypothesis:
Higher levels of FGF23 will be cross-sectionally associated with more adverse echocardiographic measures of LV structure and function.
Methods:
We conducted a cross-sectional analysis of 2086 African-American adults (66% female, median age 55) from a subset of the ARIC Study, a community-based cohort in the United States. Intact active FGF23 was assessed in blood samples collected at ARIC visit two (1990-1992). Echocardiography was performed at visit three (1993-1995) in participants recruited at the Jackson field center only. We used multivariable linear regression to evaluate the associations of FGF23 (per 15 pg/mL change) with echocardiographic measures after adjustment for traditional cardiovascular risk factors assessed at visit two. We also examined differences in observed associations by age and sex using interaction terms.
Results:
FGF23 was significantly associated with greater left atrial diameter and LV mass index (Table). A significant sex interaction was identified for LV diameter (p-interaction = 0.005). No association was observed in men while a positive association was observed among women. An adverse, decreasing trend in percent fractional shortening of the LV diameter at higher levels of FGF was stronger in individuals aged >55 (p-interaction = 0.03). No linear association was found between FGF23 and E/A ratio.
Conclusion:
FGF23 was associated with higher LV mass, larger LV size, and lower LV systolic function. These findings are consistent with results from experimental animal studies and provide evidence suggesting that cardiac structure and function may be influenced by FGF23 in humans. Prospective studies are needed to evaluate whether FGF23 is associated with change in markers of cardiac structure and function.
Fibroblast growth factor homologous factors: Evolution, structure, and function
