Correlation Between Skin Advanced Glycation End Products and Cardiac Autonomic Neuropathy Among Subjects with Type 2 Diabetes Mellitus

INTRODUCTION: Advanced glycation end products (AGEs) are frequently increased in the skin of subjects with type 2 diabetes mellitus (T2DM). This study aimed to examine the correlation of AGEs with cardiac autonomic neuropathy (CAN) in T2DM. METHODS: To this aim, 132 participants (88 men) with a mean age of 64.57 years and a median T2DM duration of 14.5 years were included. Skin AGEs were measured with AGE reader mu connect (Diagnoptics) on the dominant arm (both single and automated triplicate measurements). Diagnosis of CAN, sympathetic and parasympathetic nervous system impairment was based on the four standardised cardiovascular reflex tests (CARTs). RESULTS: On a single measurement, AGEs were increased in subjects with vs. those without CAN (3.20±0.74 vs. 2.66±0.66, p<0.001). As compared with normal results, AGEs were increased for each one of the 4 abnormal CARTs: Valsalva Ratio (3.36±0.67 vs. 2.66±0.72, p=0.004), E/I ratio (3.01±0.72 vs. 2.53±0.68, p=0.001), 30:15 ratio (3.08±0.76 vs. 2.75±0.69, p=0.011), postural hypotension (3.30±0.72 vs. 2.75±0.66, p<0.001). Similar results were obtained for triplicate measurements. DISCUSSION: Among T2DM subjects, skin AGEs appear to increase in the presence of CAN. This holds true both for sympathetic and parasympathetic nervous system impairment.