Serum Fibroblast Growth Factor 21 Is Markedly Decreased following Exercise Training in Patients with Biopsy-Proven Nonalcoholic Steatohepatitis.

BACKGROUND AND AIMS: Exercise remains a key component of nonalcoholic fatty liver disease (NAFLD) treatment. However, mechanisms underpinning the improvements in NAFLD seen with exercise are unclear. Exercise improved liver fat and serum biomarkers of liver fibrosis in the NASHFit trial. We investigated exercise's mechanism of benefit by conducting a post hoc analysis of these data to determine the relationship between serum fibroblast growth factor (FGF) 21, which is implicated in NAFLD development, and exercise. METHODS: In the 20 wk NASHFit trial, patients with nonalcoholic steatohepatitis (NASH) were randomized to receive moderate-intensity aerobic exercise training or standard clinical care. Mediterranean-informed dietary counseling was provided to each group. Change in serum FGF21 was measured after an overnight fast. RESULTS: There was a significant improvement in serum FGF21 with exercise training compared to standard clinical care (p = 0.037) with serum FGF21 reducing by 22% (-243.4 +/-349 ng/mL) with exercise vs. a 34% increase (+88.4 ng/mL +/-350.3 ng/mL) with standard clinical care. There was a large inverse association between change in serum FGF21 and change in cardiorespiratory fitness (VO2peak) (r = -0.62, 95% CI -0.88 to -0.05, p = 0.031), and on multivariable analysis, change in VO2peak remained independently associated with change in FGF21 (ß = -44.5, 95% CI -83.8 to -5.11, p = 0.031). CONCLUSIONS: Serum FGF21 is markedly decreased in response to aerobic exercise training, offering a novel mechanism to explain the observed reduction in liver fat and improvement in serum biomarkers of liver fibrosis in patients with NASH who do exercise.

The role of health literacy, depression, disease knowledge, and self-efficacy in self-care among adults with heart failure: An updated model.

BACKGROUND: Patients with inadequate health literacy and heart failure face high healthcare costs, more hospitalizations, and greater mortality. To address these negative consequences, patients need to improve heart failure self-care. Multiple factors may influence self-care, but the exact model by which they do so is not fully understood. OBJECTIVES: The objective of this study was to examine a model exploring the contribution of health literacy, depression, disease knowledge, and self-efficacy to the performance of heart failure self-care. METHODS: Using a cross-sectional design, patients were recruited from a heart failure clinic and completed validated assessments of their cognition, health literacy, depression, knowledge, self-efficacy and self-care. Patients were separated into two groups according to their health literacy level: inadequate/marginal and adequate. Differences between groups were assessed with an independent t-test. Hypothesized paths and mediated relationships were estimated and tested using observed variable path analysis. RESULTS: Participants (n = 100) were mainly male (67%), white (93%), and at least had a high school education (85%). Health literacy was associated with disease knowledge (path coefficient=0.346, p = 0.002), depression was negatively associated with self-efficacy (path coefficient=-0.211, p = 0.037), self-efficacy was positively associated with self-care (path coefficient=0.402, p<0.0005), and there was evidence that self-efficacy mediated the link between depression and self-care. There was no evidence of: mediation of the link between health literacy and self-care by knowledge or self-efficacy; positive associations between knowledge and self-efficacy or self-care; or mediation of the disease knowledge and self-care relationship by self-efficacy. Further, depression was associated with self-care indirectly rather than also directly as hypothesized. CONCLUSIONS: Self-efficacy and depression are associated with heart failure self-care. Data generated from the model suggest that healthcare professionals should actively engage all patients to gain self-efficacy and address depression to positively affect heart failure self-care.