Fibroblast growth factor-23 is independently associated with cardiac mass in African-American adolescent males

Abstract

Left ventricular hypertrophy (LVH) has been documented in hypertensive adolescents and among some with prehypertension. Obesity also appears to be associated with cardiac mass, independent of blood pressure (BP). Fibroblast growth factor-23(FGF23) is a novel biomarker positively associated with LVH in adults with and without kidney disease. The aim of this study was to determine if there was a significant and independent association of FGF23 with cardiac mass in a Black American adolescent cohort including both normotensive and prehypertensive (PH) participants with and without obesity. Measurements of BP, body mass index (BMI), plasma c-terminal FGF23, and echocardiographic measures of left ventricular mass index (LVMI) were obtained in 236 adolescents, aged 13–18 years, stratified by BMI as normal, overweight, or obese. LVMI differed significantly between normal, overweight, and obese groups (30.42±6.75 vs 33.49 ±8.65 vs 37.26±6.99 gm/m2.7; P<0.01). FGF23 was significantly higher in both overweight (53.03 RU/ml) and obese (54.40 RU/ml) compared to the normal weight (32.83 RU/ml) group; both P<0.01). In multiple linear regression analysis, variables significantly related to LVMI in males were BMI (P<0.0001), and FGF23 (P=0.005), but not BP, hsCRP or insulin. The only significant variable associated with LVMI in females was BMI (P<0.0001). In males, the contribution of FGF23 to predicting LVMI was independent of and in addition to obesity. These results suggest that FGF23 is an integral part of a complex pathway, associated with higher cardiac mass in African Americans males with excess adiposity.

The Effect of BMI, Age, Gender, and Pubertal Stage on Bone Turnover Markers in Chinese Children and Adolescents

“…However, the data from existing research on serum FGF23 levels in children with obesity are inconsistent. Some studies reported an increase in serum FGF-23 concentration in overweight/obese children ( 39 , 40 ) and a positive association between serum FGF23 and BMI ( 39 ). In contrast, some studies detected decreased serum FGF-23 levels in obese subjects ( 41 ) and inverse correlations with fasting insulin levels ( 41 ) as well as fasting glucose levels ( 42 ).…”

Regulation of fibroblast growth factor 23 (FGF23) in health and disease

“…The association between FGF23 and insulin deficiency (type 1 diabetes) and resistance (type 2 diabetes) is, however, complex. In many cross‐sectional studies, FGF23 is positively correlated with obesity, diabetes or HOMA‐IR, a parameter indicating insulin resistance . According to other studies, FGF23 is inversely associated with insulin resistance .…”

Fibroblast growth factor 23—Klotho and hypertension: experimental and clinical mechanisms

“…Both FGF23 and leptin levels are elevated in patients with obesity [91], and obese children frequently develop HTN, as illustrated in a study that showed 35% of 260,000 overweight and obese children had HTN [92]. FGF23 levels are higher in normotensive obese children, highlighting that FGF23 elevations are not necessarily accompanied by increases in BP and raising the possibility that FGF23 may contribute to cardiac hypertrophy in children with obesity before they develop HTN [93].…”