Sympathetic activity and cardiovascular risk markers in non-diabetic and diabetic Mexican older adults

Abstract

Purpose: To compare the SNS activity and metabolic markers associated to CVD in type 2 diabetic (T2D) and non-diabetic (ND) Mexican older adults. Methods: Volunteers were 11 T2D (Age = 60.8 ± 5.2 yr., body mass index [BMI]= 29.9 ± 4.6 kg/m2) and 17 ND (Age = 64 ± 4.8 yr., BMI = 28.4 ± 4.1 kg/m2) older adults residing in Baja California, Mexico. Morning blood serum samples were collected after 8-h fasting following body composition analysis (InBody 770, Cerritos, CA). A 5-min resting ECG recording (BioRadio, Cleveland, OH) was used to analyze HRV. Time and frequency domain analysis were assessed with Kubios HRV 3.1 software (Kubios Oy, Finland). Results: Between-group differences were found on blood glucose (T2D = 171.9±91.6 vs. ND = 80.17±12.0mg/dL, p < 0.001), and triglycerides (T2D = 266.9±126.17 vs. ND = 60.54 ± 47.8mg/dL, p < 0.02). Non-significant between-group differences were found on cholesterol (T2D = 183.0±45.1 vs. ND = 180.9±29.7mg/dL, p = 0.88), HDLc (T2D = 60.54±55.8 vs. ND = 47.88±20.73mg/dL, p = 0.92) and LDLc levels (T2D = 84.4±44.6 vs. ND = 107.84±26.74mg/dL, p = 0.22). The HR (T2D = 72.6±11.5 vs. ND = 71.7±7.8bpm, p = 1.0), beat-to-beat intervals (RR) (T2D = 845.7±128.7 vs. ND = 843.7±93ms, p = 0.94), Root Mean Square of the Successive Differences (RMSSD) (T2D = 68.7±58.0 vs. ND = 45.6±31.2ms, p = 0.45) and relative successive beats with > 50ms of difference (pNN50) (T2D = 23.4±25.5 vs. ND = 9.7±13.7%, p = 0.32) were similar in both groups. High- (T2D = 48.14±24.64 vs. ND = 45.5±22.9n.u., p= 0.67) and Low-frequency (T2D = 51.7±24.5 vs. ND = 54.0±23.3n.u., p= 0.70) time domains and LF/HF ratio (T2D = 2.0±2.4 vs. ND = 2.4±3.0, p = 0.68) were similar in both groups. Conclusions: Diabetic conditions did not affect substantially SNS activity compared with non-diabetic condition in a sample of Mexican older adults.