Context: Adiponectin inhibits protein synthesis in cardiac myocytes, thereby opposing the effect of cardiac workload and trophic factors (in particular, insulin) on left ventricular (LV) mass and wall thickness (WT).
Objective: We tested whether adiponectin and its isoforms are related to LV mass, WT, and function independently of metabolic factors.
Design: This was a cross-sectional study.
Subjects: The study included 77 healthy volunteers (42 men) aged 30-59 yr with normal LV structure and function.
Main outcome measures: Insulin response and insulin sensitivity were assessed by oral glucose tolerance test and euglycemic hyperinsulinemic clamp. LV mass, WT, stroke work, chamber function, and myocardial longitudinal function were evaluated by standard Doppler echocardiography and tissue Doppler imaging. Total and molecular isoforms of adiponectin were measured in plasma.
Results: By multivariate analysis, independent factors affecting LV mass were sex, body mass index, stroke work, and current smoking (R(2) = 0.66). Independent correlates of LV WT were age, stroke work, and plasma adiponectin (standardized r = 0.28, 0.41, and -0.26, P at least < 0.005, R(2) = 0.48). LV longitudinal late diastolic velocity was independently related to age, body mass index, and adiponectin (standardized r = 0.20, 0.26, -0.33, P at least < 0.05, R(2) = 0.30). High-molecular-weight adiponectin (47% of total), but not lower molecular-weight isoforms, insulin sensitivity, or other metabolic factors, was inversely and independently related to WT (standardized r = -0.27, P < 0.01) and myocardial longitudinal late diastolic velocity (standardized r = -0.28, P < 0.05).
Conclusion: In healthy subjects, circulating total and high-molecular-weight adiponectin are related to LV WT and diastolic function, independently of age and metabolic factors.