Diabetic Cardiovascular Autonomic Neuropathy: Effects of Simvastatin and Omega-3 Polyunsaturated Fatty Acids on Insulin Resistance and Lipid Profile Parameters

Abstract

Introduction. Currently, there is no unified treatment algorithm of cardiac autonomic neuropathy (CAN) in patients with type 2 diabetes mellitus (T2DM). The aim of the study was to investigate the effects of simvastatin (SIM) and -3 polyunsaturated fatty acids (-3 PUFAs) on blood lipid profile and insulin resistance (IR) in patients with type 2 diabetes mellitus and definite cardiac autonomic neuropathy. Materials and methods. The study involved 72 patients with T2DM and definite CAN. Patients were divided into four groups: 1st - received standard hypoglycemic therapy - control (n = 15); 2nd (n = 22) – in addition simvastatin (SIM) 20.0 mg/q.d.; 3rd (n = 18) - in addition 1 capsule/q.d. of the ω-3 PUFAs; 4th (n = 17) - in addition SIM 10.0 mg/q.d and 1 capsule/q.d of the ω-3 PUFAs for three months. The concentration of glucose, glycated hemoglobin A1c, immunoreactive insulin (IRI), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG) in the blood were determined. Homeostasis model assessment IR (HOMA-IR), atherogenic coefficient (AC), TG/LDL-C, TG/TC, TG/LDL-C and TG and glucose index (TyG) were calculated. Results. Prescription of SIM was accompanied by a statistically significant decrease in TC, LDL-C, TG concentrations. In parallel, SIM induced a decrease of AC, TG/HDL-C, increase in HDL-C, and does not affect the IRI, HOMA-IR, TG/LDL-C, TG/TC, TC/LDL-C/HDL-C, TyG. The use of ω-3 PUFAs has contributed to a significant reduction in TG, AC, TG/LDL-C, TG/TC, TG/HDL-C, TyG index, increase in HDL-C, and was not accompanied by changes in IRI content, HOMA-IR, TC, LDL-C, and TC/LDL-C/HDL-C. The combined prescription of SIM and -3 PUFAs was accompanied by more pronounced, statistically significant changes in the blood lipid spectrum, as well as a decrease in the IRI and HOMA-IR. Conclusions. Obtained results justify the appropriateness of combined simvastatin and -3 polyunsaturated fatty acids prescription to patients with type 2 diabetes mellitus and definite cardiac autonomic neuropathy. Keywords: diabetes mellitus, cardiac autonomic neuropathy, treatment.