[Deep breathing test type I diabetic patients and parameters of spectral analysis]

Nervous system injury, affecting also its autonomic part, occurs in the natural course of chronic complications in patients with type 1 and 2 diabetes. The aim of the study was to compare heart rate frequency analysis parameters at rest and after deep breathing test in healthy persons and in the group of type 1 diabetes patients without complications. The study was performed in 34 patients with type 1 diabetes without chronic complications (N0), hospitalized in the Chair and Department of Metabolic Diseases in 1993-1996. The control group (K) consisted of 23 healthy persons. All diabetic patients underwent examinations to identify chronic complications of the disease. Aiming at answering the question how simple physiological tests influence frequency parameters of heart rate variability, assessment of VLF, LF and HF parameters was performed at rest and after the deep breathing test. In both groups K and N0 no changes were observed in the spectrum power within VLF values after deep breathing compared to the initial values. In the group K the deep breathing test significantly (p < 0.001) increased spectrum power within LF values, whereas in the group N0 the test did not produce statistically significant changes of this parameter compared to the initial values. In the control group K as well as in diabetic patients N0 the test caused significant (p < 0.01 and p < 0.001, respectively) decrease in the HF spectrum power in comparison to the values at rest. VLF/LF ratio after the deep breathing test as well as LF/HF ratio at rest were significantly lower in the group K compared to the group N0.

Analysis of the autonomic nervous system imbalance may be an indispensable tool in the early diagnostics of patients with type 1 diabetes. Results of spectrum analysis may be useful in cases when classical Ewing battery tests do not identify autonomic dysfunction.