Wavelet phase coherence analysis between the respiratory activity and the microcirculation: the effects of type 1 diabetes

Abstract

Microvascular perfusion is modulated by the breathing activity. However, to the authors’ knowledge, no study has attempted to assess the pathological deterioration of this physiological coupling in diabetes, which is related to structural and functional alterations of the microvasculature. On this basis, a phase coherence analysis was conducted to identify a possible weakening of the time-phase relationship between the breathing rhythm and the peripheral pulse, measured with laser Doppler flowmetry. Two groups of 21 healthy subjects and 21 type 1 diabetic (T1D) patients were evaluated in this retrospective study: a significant phase coherence was detected for the area beneath the diastolic phase of the peripheral pulse (median: 0.78; IQR: 0.20), in 81.0% of the controls; however, the analysis of the T1D group highlighted a considerable loss of synchronization, with significant values obtained in only 33% of the cases (median: 0.53; IQR: 0.15). This result may yield a valuable biomarker for the detection of diabetic microangiopathy.