Sleep and IOP?

One of the things which I have not gotten around to testing is the effect of quality of sleep on IOP. Has anyone done any tonomotry testing attempting to pinpoint sleep quality/quantity as a variable? Also, would such things as going to bed early/late, or getting up early/late have any effect? Just curious if anyone has noticed any patterns in IOP related to amount of sleep, restfullness, awakening and rising time, etc. I will have to start paying more attention to this, but so far I have not varied my sleep patterns enough to make an observation.