Growth differentiation factor 15 as an integral marker of the clinical and functional status of patients with non-valvular atrial fibrillation

Abstract
Introduction. Growth Differentiation Factor 15 (GDF-15) is known to be an independent predictor of cardiovascular and all-cause mortality, as well as major bleeding in patients (pts) with non-valvular atrial fibrillation (AF). Since GDF-15 is expressed by a wide array of cells in response to inflammation and myocardial stress, it is interesting to study which clinical and functional parameters are most associated with the level of GDF-15 in pts with non-valvular AF and preserved left ventricular ejection fraction. Aim. To study the relationship of GDF-15 level in blood serum with parameters of clinical and functional status and to determine independent predictors of GDF-15 level in pts with non-valvular AF. Material and methods. 87 pts with non-valvular AF were studied, with an average age of 56.9±9.2 years. A general clinical examination, echocardiography and laboratory tests were performed, including fasting serum glucose (mmol/l),highly sensitive C-reactive protein (h/s CRP) (mg/l), creatinine level (mkmol/l) and subsequent calculation of glomerular filtration rate (ml/min/1.73m2), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) (pg/ml). The level of GDF15 (pg/ml) in blood serum was determined using an enzyme immunoassay with the help of the human GDF-15/MIC-1 ELISA analytical kit (BioVender, Czech Republic). Results. The increase in the GDF-15 level was associated with ageing, ischemic heart disease, severity of arterial hypertension and heart failure, raising the risk of stroke, according to the scale CHA2DS2-VASc, disturbances of carbohydrate metabolism and obesity, increasing the levels h/s CRP and NT-proBNP, enlargement of the right and left atria, signs of diastolic left ventricular dysfunction and structural remodeling in the form of eccentric hypertrophy. Multiple linear regression analysis revealed 2 independent predictors of GDF-15 levels: age and fasting glucose. Conclusion. GDF-15 appears as an integral biomarker of age-related metabolic disorders and structural and functional changes in the heart, which opens up prospects for further study of its prognostic significance in pts with non-valvular AF.