Autonomic dysfunction in non-diabetic terminal uraemia.

Area of Science:

• Cardiology
• Nephrology
• Neurology

Background:

• Autonomic dysfunction is common in patients with end-stage renal disease (ESRD).
• Heart rate variability (HRV) via R-R variations in ECG reflects autonomic function.
• Parasympathetic vagal reflex impairment is a key indicator of autonomic dysfunction.

Purpose of the Study:

• To investigate autonomic dysfunction, specifically parasympathetic activity, in non-diabetic patients with terminal uraemia undergoing intermittent hemodialysis.
• To assess the relationship between R-R variations, polyneuropathy, and hemodialysis treatment.

Main Methods:

• Electrocardiogram (ECG) R-R variations were analyzed in 44 non-diabetic patients with terminal uraemia.
• Patients were undergoing intermittent hemodialysis.
• Neuropathy was assessed using a polyneuropathy index.

Main Results:

• Severe impairment of the parasympathetic vagal reflex was observed in patients.
• Only mild signs of diffuse polyneuropathy were present, suggesting autonomic dysfunction precedes significant nerve damage.
• Hemodialysis showed no acute effect on the measured R-R variations.
• No correlation was found between R-R variations and the polyneuropathy index or total dialysis duration.
• Patients with various underlying kidney diseases (chronic glomerulonephritis, pyelonephritis, polycystic kidney disease) exhibited similar levels of impairment.

Conclusions:

• Terminal uraemia leads to significant autonomic dysfunction, particularly affecting the parasympathetic nervous system, even with minimal peripheral neuropathy.
• Intermittent hemodialysis does not acutely impact this parasympathetic impairment.
• Autonomic dysfunction in ESRD is a complex issue potentially independent of dialysis treatment duration or severity of polyneuropathy.