FIG. 53:  This Figure illustrates the principal finding from the study introduced in the previous Figure,^[38] distributed according to the 24-hour time intervals shown on the x-axis, midnight to 6.00 AM, 6.00 AM to noon, noon to 6.00 PM. and 6.00 PM. to midnight. 

Looking at the general population (white bars) based on data from the literature, only about 16% of sudden deaths occurred in the nighttime hours of midnight to 6.00 AM, whereas most of the deaths appeared to occur in the early morning, between 6.00 AM and noon. 

However for the patients who died of sudden cardiac arrest, in whom we knew the time of death and whether or not they had OSA, only 21% of those without OSA (yellow bars) died during the nighttime hours (midnight to 6.00 AM) whereas 41% died in the morning after waking, between 6.00 AM and noon, which is what the literature would predict. 

In contrast, in patients who died suddenly and in whom a previous diagnosis of OSA had been documented with polysomnography, there was a higher likelihood of sudden death occurring during sleep time, with a decreased likelihood of sudden death occurring later during the morning hours.