[Autonomic imbalance in patients with metabolic syndrome: role in the development of hyperfiltration--an early marker of renal lesions].

Aim: to study the impact of the autonomic nervous system on the development of renal lesion in patients with metabolic syndrome (MS).
Subjects and Methods: One hundred and nine patients (45 females and 54 males) aged 29 to 72 years who had MS were examined. Glomerular filtration rate (GFR) was estimated using the Cockroft-Gault formula, by correcting the obtained result on the body surface. According to the level of GFR, the patients were divided into 3 groups: 1) 30 MS patients with hyperfiltration (GFR > 110 ml/min/1.73 m2); 2) 55 patients with normal GFR (110-60 ml/min/1.73 m2); 3) 24patients with lower GFR ( < 60 ml/min/1.73 m2). All the patients underwent physical examination; autonomic tonus was examined by 24-hour cardiac rhythm variability (CRV) study using the Holter monitoring system, by applying the time analysis. The presence of autonomic dystonia syndrome (ADS) and its degree were determined by a questionnaire to detect autonomic nervous system (ANS) dysfunction.
Results: Each of 3 groups was found to have signs of autonomic imbalance with a preponderance of sympathetic activity with decreased parasympathetic activity, these impairments being more pronounced in Group 1. The obtained regulation reflects the entire decrease in autonomic actions on the cardiovascular system in patients with MS and suggests the maximum hyperactivation of the sympathetic ANS in early-stage renal lesion--hyperfiltration
Conclusion: When the first signs of renal lesion (hyperfiltration) occur in patients with MS, there is significant hypersympaticotonia that promotes the progression of target organs, including the kidneys.