Figure 1.

Single factorial analysis of the number of central apneic events (CAEs) in relation to the respective REM sleep duration by group (severity of OSA: mild, moderate, severe) and sleep phase (REM, NREM). In the group of severely affected OSA patients, the frequency of CAEs was significantly increased in the NREM phase when compared to the one in the REM phase, when adjusted for the duration of the REM phase. This was not the case in the group of moderately and mildly affected OSA patients. The symbols overlap in many cases, and most data points were at the value 0. Unfortunately, it is difficult to present this clearly without distorting the intended message of the plot. Due to the overlay, not all data points are clearly visible.