The impact of gender and left atrial blood stasis on adiponectin levels in non-valvular atrial fibrillation

Background Obesity is a risk factor for non-valvular atrial fibrillation (NVAF), diabetes mellitus, and hypertension. Adiponectin, a unique biomarker of adipose tissue, has antiinflammatory, insulin-sensitizing, and antiatherogenic properties and is known to be higher in women. The relationship between adiponectin, gender, and thromboembolic risk in atrial fibrillation however is unknown. Methods The relationship between gender, adiponectin levels, and echocardiographic measures of blood stagnation and left atrial appendage thrombus (LAAT) was assessed in 209 patients with NVAF (55 women and 154 men; mean age 63 ± 14 years) compared to 70 normal sinus rhythm controls (29 women and 41 men; mean age 64 ± 14 years). Total adiponectin was measured by solid-phase ELISA. Demographic and clinical variables of CHADS₂ and CHA2DS2-VASc were collected, and spontaneous echocardiographic contrast (SEC), left atrial appendage emptying velocity (LAAEV) and left atrium volume index (LAVI) were measured prospectively. Results Elevated adiponectin was associated with advanced cardiovascular pathology and permanent arrhythmia but only in men with NVAF. In NVAF men, a step-wise increase in adiponectin levels was noted relative to increasing intensity of SEC and decreasing LAAEV. Adiponectin level > 16657 ng/ml predicted LAAT (OR: 3.66; 95% Cl: 1.21-11.48; p = 0.022) after adjustment for CHADS2 score in men but not in women with NVAF. Conclusions There is a direct correlation between elevated adiponectin level and the degree of left atrial blood stasis in men but not in women with NVAF. High adiponectin levels can be used as an important variable in the prediction of LAAT.