Short-term changes in klotho and FGF23 in heart failure with reduced ejection fraction—a substudy of the DAPA-VO2 study

The klotho and fibroblast growth factor 23 (FGF-23) pathway is implicated in cardiovascular pathophysiology. This substudy aimed to assess the changes in klotho and FGF-23 levels 1-month after dapagliflozin in patients with stable heart failure and reduced ejection fraction (HFrEF). The study included 29 patients (32.2% of the total), with 14 assigned to the placebo group and 15 to the dapagliflozin, as part of the double-blind, randomized clinical trial [DAPA-VO2 (NCT04197635)]. Blood samples were collected at baseline and after 30 days, and Klotho and FGF-23 levels were measured using ELISA Kits. Between-treatment changes (raw data) were analyzed by using the Mann-Whitney test and expressed as median (p25%–p75%). Linear regression models were utilized to analyze changes in the logarithm (log) of klotho and FGF-23. The median age was 68.3 years (60.8–72.1), with 79.3% male and 81.5% classified as NYHA II. The baseline medians of left ventricular ejection fraction, glomerular filtration rate, NT-proBNP, klotho, and FGF-23 were 35.8% (30.5–37.8), 67.4 ml/min/1.73 m2 (50.7–82.8), 1,285 pg/ml (898–2,305), 623.4 pg/ml (533.5–736.6), and 72.6 RU/ml (62.6–96.1), respectively. The baseline mean peak oxygen uptake was 13.1 ± 4.0 ml/kg/min. Compared to placebo, patients on dapagliflozin showed a significant median increase of klotho [Δ+29.5, (12.9–37.2); p = 0.009] and a non-significant decrease of FGF-23 [Δ−4.6, (−1.7 to −5.4); p = 0.051]. A significant increase in log-klotho (p = 0.011) and a decrease in log-FGF-23 (p = 0.040) were found in the inferential analysis. In conclusion, in patients with stable HFrEF, dapagliflozin led to a short-term increase in klotho and a decrease in FGF-23

Short-term Changes in Hemoglobin and Changes in Functional Status, Quality of Life and Natriuretic Peptides After Initiation of Dapagliflozin in Heart Failure With Reduced Ejection Fraction

Background: We aimed to evaluate the effect of dapagliflozin on short-term changes in hemoglobin in patients with stable heart failure with reduced ejection fraction (HFrEF) and whether these changes mediated the effect of dapagliflozin on functional capacity, quality of life and NT-proBNP levels. Methods: This is an exploratory analysis of a randomized, double-blinded clinical trial in which 90 stable patients with HFrEF were randomly allocated to dapagliflozin or placebo to evaluate short-term changes in peak oxygen consumption (peak VO2) (NCT04197635). This substudy evaluated 1- and 3-month changes in hemoglobin levels and whether these changes mediated the effects of dapagliflozin on peak VO2, Minnesota Living-With-Heart-Failure test (MLHFQ) and NT-proBNP levels. Results: At baseline, mean hemoglobin levels were 14.3 ± 1.7 g/dL. Hemoglobin levels significantly increased in those taking dapagliflozin (1 month: + 0.45 g/dL (P = 0.037) and 3 months:+ 0.55 g/dL (P = 0.012)]. Changes in hemoglobin levels positively mediated the changes in peak VO2 at 3 months (59.5%; P < 0.001). Changes in hemoglobin levels significantly mediated the effect of dapagliflozin in the MLHFQ at 3 months (-53.2% and -48.7%; P = 0.017) and NT-proBNP levels at 1 and 3 months (-68.0%; P = 0.048 and -62.7%; P = 0.029, respectively). Conclusions: In patients with stable HFrEF, dapagliflozin caused a short-term increase in hemoglobin levels, identifying patients with greater improvements in maximal functional capacity, quality of life and reduction of NT-proBNP levels.This work was supported in part by an unrestricted grant from Astra Zeneca (ESR-17-13447), Unidad de Investigación Clínica y Ensayos Clínicos INCLIVA Health Research Institute, Spanish Clinical Research Network (SCReN; PT17/0017/0003 y PT20/00100), and CIBER Cardiovascular [grant numbers 16/11/00420, 16/11/00403, and 16/11/00486]