Context: Obese Hispanic adolescents (OHAs) with dysglycemia have increased cardiovascular disease risk burden.
Objective: To investigate if nonalcoholic fatty liver disease (NAFLD) confers added risk for endothelial dysfunction in these youth.
Design: Cross-sectional study.
Setting: Academic institution.
Participants: Thirty-six OHAs (15.3 ± 0.4 years), 20 with prediabetes and 16 with type 2 diabetes, with and without NAFLD.
Intervention: Evaluation of reactive hyperemia index (RHI) and augmentation index (AIx) by peripheral arterial tonometry; muscle, hepatic, and adipose tissue insulin sensitivity (IS; hyperinsulinemic-euglycemic clamp 80 mu/m2/min, with [6,6 2H2]glucose and [2H5] glycerol); body composition; and abdominal and hepatic fat by magnetic resonance imaging/spectroscopy.
Outcome measures: RHI and AIx.
Hypothesis: OHAs with dysglycemia and NAFLD have worse RHI and AIx vs those without NAFLD.
Results: The NAFLD (n = 23) and non-NAFLD (n = 13) groups were of similar age, sex, glycemic status, body mass index, % body fat and abdominal fat. The NAFLD group had higher hepatic fat (P < 0.001) lower skeletal muscle IS (P = 0.01), hepatic IS (P = 0.01), and adipose tissue IS (P = 0.04). The NAFLD vs non-NAFLD group had lower RHI (1.4 ± 0.05 vs 1.7 ± 0.09, P = 0.002), greater AIx (-6.0 ± 1.6 vs -12.0 ± 2.1, P = 0.03). Hepatic fat was inversely related to RHI (r = -0.49, P = 0.002) and positively related to AIx (r = 0.45, P = 0.006). Hepatic IS (r = -0.42, P = 0.01) and adipose IS (r = -.54, P = 0.001) correlated with arterial stiffness (AIx).
Conclusion: In OHAs with dysglycemia, NAFLD is associated with worse endothelial function. RHI and AIx were related to hepatic fat content. Vascular stiffness was related to hepatic and adipose tissue insulin resistance.
Keywords: NAFLD; endothelial function; hepatic fat; inflammatory markers; insulin resistance.