Assessment of autonomic dysfunction in iron-deficient anemic infants by cardio-respiratory demodulation

To assess the Autonomic Nervous System development in iron-deficient anemic infants during quiet sleep, the authors used the modified complex demodulation analysis which allows for a continuous evaluation of the phase and amplitude relationships between the heart rate and breathing oscillations. Iron deficient infants have a lower demodulation amplitude and more time spent in isolated sudden phase shifts than the control infants, suggesting a delayed autonomic nervous system maturation, especially in vagal activity