Leptin, adiponectin, tumor necrosis factor α, and irisin concentrations as factors linking obesity with the risk of atrial fibrillation among inpatients with cardiovascular diseases.

Background: The endocrine function of adipose tissue and skeletal muscles mediates the risk of cardiovascular complications of obesity.

Aims: The aim of this study was to determine the associations of leptin, adiponectin (ADA), tumor necrosis factor α (TNF‑α), and irisin levels with the diagnosis of atrial fibrillation (AF) on admission to the hospital as well as parameters of transthoracic echocardiography among inpatients with cardiovascular diseases (CVDs).

Methods: The study included 80 consecutive patients hospitalized due to paroxysmal or persistent AF and a control group of 165 age- and sex‑matched individuals admitted due to exacerbation of chronic CVD. In all participants, we assessed serum leptin, ADA, TNF‑α, and irisin concentrations, body composition determined by bioelectrical impedance analysis, and transthoracic echocardiographic parameters.

Results: Compared with controls, patients with AF had greater fat mass (FM), higher serum leptin levels and lower levels of ADA, TNF‑α, and irisin when indexed to body surface area, FM, and visceral adiposity. Hyperleptinemia slightly increased the risk of AF (odds ratio [OR], 1.02; 95% CI, 1.01-1.03; P <0.01). The correlation was stronger after indexation to FM (OR, 1.34; 95% CI, 1.01-1.81; P <0.05). The coefficients of significant correlations with echocardiographic parameters were stronger for irisin than for adipocytokines: 0.16 to 0.35 and 0.12 to 0.22, respectively.

Conclusions: Adipocytokines and irisin exert a significant but weak effect on heart chamber size and affect the risk of AF occurrence. Their blood concentrations do not seem to be related simply to body composition but probably depend on individual variations in adipocytokine and myokine secretion as a result of numerous factors.