Methods and apparatus perform periodic breathing detection, such as Cheyne-Stokes respiration detection. The detection may be performed by one or more processors, such as by analysis of data from one or more sensors. In some cases, the detection may be based on an electrocardiogram (ECG) signal, such as from ECG electrodes and/or an accelerometer signal, such as from an accelerometer. An occurrence of periodic breathing may be detected based on features derived from the signal(s). For example, detection may be based on deriving a respiration signal from the sensed signal(s) and/or analysis of RR interval times or relative QRS amplitude values, which may be evaluated on a segment-by-segment basis. The detection may provide monitoring and reporting of the occurrence of periodic breathing by a monitoring device and/or provide a basis for controlling changes to a provided respiratory treatment or therapy, such as by a respiratory pressure therapy device.
