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Bilovol et al. Relationship between atrial fibrillation, BMI and adipokines

disease (CVD), including an increased risk of incidence and CVD. Adiponectin is reduced in obesity, CHD, HF,
of sudden cardiac death, atrium fibrillation and other AF and T2DM, and increased following weight loss.
form of arrhythmias . Adiponectin levels were independently associated
[1]
with the incident of AF [16,17] . However, it remains
In contrast, a large review from Flegal et al. analyzed unclear whether these are markers of failed regulatory
[3]
97 studies of 2.9 million individuals, including > pathways that lead to AF or are directly involved in AF
270,000 deaths, and demonstrated that optimal pathogenesis.
survival occurred in “overweight” patients [body mass
index (BMI): 25 to 30 kg/m ], who had a significant 6% Our study aimed to elucidate the causal relationship
2
lower mortality than the “normal-weight” BMI cohort between AF and BMI or adipokine levels, specifically
(BMI: 18.5 to 25 kg/m ) . serum leptin and high-molecular-weight adiponectin
2 [3]
(HMWAN), among the general population.
Patients with elevated BMI, but normal insulin sensitivity,
lipid profiles and blood pressure (BP), are considered METHODS
to be metabolically healthy obesity (MHO) . Some
[4]
epidemiological data suggest that MHO carries a
lower risk of CVD, lower risk of AF development and This study comprised 398 patients randomly selected
less all-cause mortality than being normal weight yet while visiting the out-patient unit due to any reason,
metabolically unhealthy . The precise mechanism except acute heart pathology, provided they had not
[5]
that induces AF in obesity is still unknown. Metabolic had heart rate disorders in their past medical history.
comorbidities are common in obese people and could
be the main reason for increased AF risk and total Among allotted patients there were 142 with arterial
cardiovascular risk, apart from obesity itself. There are hypertension (AH) (35.7%), 118 suffering from ischemic
several proposed mechanisms that connect obesity heart disease (29.6%), 73 with diabetes mellitus II type
and AF [6-10] . (DM-2) (18.3%), provided DM-2 was compensated.

Enhanced neurohormonal activation, impaired insulin Also excluded were those patients who had developed
tolerance, dyslipoproteinemia, hypertension and kidney, liver diseases, heart diseases, heart failure
pathological changes in circulating renin-angiotensin- (more than 2 functional class according to New York
aldosterone system accompanies obesity and may Heart Association), chronic obstructive lung pathology,
contribute to left atrial enlargement and electrical malignant neoplasms or alcoholism.
instability, which may result in AF development [11] .
Patients’ age ranged from 37 to 56 years old (mean
Studies on the mechanisms by which obesity induces age: 41.4 ± 2.3 year). All patients involved in this
AF show that obesity causes atrial arrhythmogenic study were examined according to the same protocol.
remodeling. Progression of atrial fibrosis is a key event Anthropometry was assessed with measurements
in the pathogenesis of AF [12,13] , and can be caused by of waist circumference and BMI calculated by Kettle
aging, underlying cardiac diseases, systemic diseases formula. Additionally, BP was measured along with
or inflammatory processes, or AF itself. Obese a panel of laboratory tests: fasting serum glucose
individuals, even without cardiovascular disease, have (glucosoxidative approach); serum lipoproteins
left atrium (LA) enlargement [14] and different electrical [serum cholesterol, triglycerides (TG), cholesterol of
properties, such as slower conduction from the LA high-density lipoprotein (HDL) by enzyme colorimetric
entering the pulmonary vein (PV) and a significantly approach with kit of “Human” (Germany)]; C-reactive
shorter effective refractory period in the LA and PV . protein (CP) by solid phase enzyme immunoassay
[15]
(EIA) (NycoCard CRP, Axis-Shield); serum Leptin by
Adipokines are bioactive proteins produced by the EIA kit Leptin ELISA [Diaghostics Biochem Canada
adipose compartment that have wide-ranging effects Inc (DBC Inc) cat № ABIN362629 CAN-L-4260]; and
across organs and tissues. Leptin and adiponectin are serum HMWAN by EIA with use of kit DRG (USA). The
both closely related with obesity and have recently homeostatic model assessment of insulin resistance
been implicated with AF. These hormones are secreted (HOMA-IR) was calculated: НОМА-IR = insulin, mcU/mL
primarily by adipocytes, while the stromovascular tissue × glucose, mmol/L ÷ 22.5).
surrounding fat secretes tumor necrosis factor-alpha
(TNF-α) and macrophages secrete resistin [16,17] . These Overweight patients (BWI: 25-29.9 kg/m ) and those
2
2
adipokines have been proposed as links between with AO and BMI ≥ 30 kg/m were classified according
adiposity and insulin resistance, glucose deregulation, to Wildman criteria (2008) as “MHO” and “metabolically
Vessel Plus ¦ Volume 1 ¦ December 28, 2017 197