Adiponectin Levels Are Elevated in Patients With Pulmonary Arterial Hypertension

Background: In addition to insulin-sensitizing effects, adiponectin influences several mechanisms involved in pulmonary arterial hypertension (PAH) pathobiology. Insulin resistance has been associated with PAH, and elevated adiponectin levels have been described in left heart failure (HF) as a response to the increased metabolic stress. No studies have been performed in right HF or PAH patients. Hypothesis: Compared to healthy controls, PAH patients have a different plasma adipocytokine profile, higher insulin resistance, and higher inflammatory systemic activation. Methods: A case-control study was conducted in PAH patients individually matched for sex, age, and body mass index. We characterized the clinical features, functional status (6-minute walking test), and hemodynamic profile of cases (n = 25). We measured insulin resistance (homeostasis model assessment and high-density lipoprotein/triglycerides ratio), inflammatory systemic activation (high-sensitivity C-reactive protein), and plasma adipocytokine profile (adiponectin, leptin, visfatin, and resistin) in cases and controls. Results: PAH patients had significantly higher adiponectin levels than controls (12.4 6.9 vs 8.1 +/- 4.5 mu g/mL; P < 0.05) and higher high-sensitivity C-reactive protein (2.96 +/- 3.2 vs 1.08 +/- 1.1; P < 0.05). No statistically significant differences were found in plasma levels of leptin, visfatin, and resistin between groups. Conclusions: Adiponectin levels are increased in PAH patients compared to controls. Further studies are needed to study the potential role of adiponectin as a PAH biomarker.