Spectral Analysis of Spontaneous Heart Rate Variation in Diabetic Patients

In 28 diabetic patients and 62 control subjects spectral analysis of spontaneous beat-to-beat RR interval variations was performed. The spectral analysis focused on the dominant frequency of the mid-frequency band (0.04–0.12 Hz) or baro-oscillatory phenomenon (BOP). Compared with control subjects the dominant frequency of the BOP (BOP frequency) in the diabetic patients was lower (p < 0.001), and the difference increased with age. The shift of the BOP frequency was positively correlated with the reduced variation in heart rate during deep breathing (r = 0.80, p < 0.001) in the diabetic patients. These findings indicate that determination of the BOP frequency is a useful method for assessing cardiovascular autonomic function, supplementary to the known cardiovascular reflex tests. Measurement of the BOP frequency has the advantage that no active patient co-operation is required.