Cardiovascular Autonomic Tone is Related to Insulin Resistance in Prediabetes
Author: Dimova, Rumyana B., Chakarova, Nevena Y., Grozeva Greta G., Kirilov, Georgi G., Dakovska, Lilia, N., Tankova, Tsvetalina I.
Abstract:
Aim: A total of 265 subjects with prediabetes (104 males), of mean age 44,7±12,4 years and mean BMI 30,5±6,2 kg/m2, divided according to HOMA-IR – with HOMA-IR ≥2,5 and with HOMA-IR <2,5, and according to the presence of CAD – with CAD and without CAD, were enrolled. Glucose tolerance was evaluated during a standard oral glucose tolerance test in all participants. The glucose tolerance was defined according to 2006 WHO criteria. Fasting and 120-min plasma glucose were examined by a hexokinase enzyme method and immunoreactive insulin at fasting by the ECLIA method, and HOMA-IR and НОМА-β were calculated. The autonomic nervous system function was evaluated with an АNX-3.0 autonomic monitoring system using standard clinical tests: deep breathing, Valsalva maneuver, and standing.
Material and methods: We compared 46 long-term survivors, aged 9-32 years (mean age 20,6±6,2 y), to 35 age- and sexmatched controls and assessed anthropometric features and biochemical and hormonal parameters. BMD, BMD Z-score, bone mineral content (BMC), fat mass (FM), lean mass (LM) and appendicular muscle mass (AMM) were measured by whole body Dual-energy X-ray absorptiometry (DEXA). Participants’ physical activity (PA) was assessed by questionnaires and interview.
Results: CAD was found in 15,2% of the HOMA-IR ≥ 2,5 group in comparison to 9,2% in the HOMA-IR < 2,5 group (OR 1,67 (95% CI:0,76-3,64), p=0,036). HOMA-IR is higher in subjects with abnormal deep breathing, standing test and CAD (p=0,010, p=0,008, p=0,015, respectively).
Conclusion: CAD appears to be associated with insulin resistance, assessed by HOMA-IR, in the early stages of impaired glucose tolerance.
Key words: cardiovascular autonomic dysfunction, insulin resistance, prediabetes
