Delayed Sleep and Sleep Loss in University Students

Abstract A sample of 211 university first-year psychology students completed a 37-item questionnaire of sleep habits and difficulties. The most commonly reported sleeping difficulty of this population was frequent difficulty in falling asleep (18%), whereas only 9% of the sample had frequent difficulty staying asleep. There was a marked delay (over 90 minutes) in time of going to bed and waking up on weekends compared to weeknights. About 50% of the sample complained of insufficient sleep and estimated needing about half an hour more sleep on the average to feel rested. A subgroup of the sample (17%) fit the criteria for at least a mild form of delayed sleep phase syndrome (DSPS). This delayed sleep pattern presumably arises from a delay in their endogenous biological rhythms that creates difficulty in falling asleep early enough to get sufficient sleep before necessary weekday morning awakening. Compared to the whole sample, the DSPS group less often reported sufficient sleep on weekdays and more often reported drowsiness and irritability during the day from insufficient sleep. Academic performance in their psychology course was lower for the DSPS group than for the rest of the sample and also lower than a group of sleep-disturbed but not drowsy students. It appears that delayed sleep phase syndrome may be a significant problem in university student populations and may result in chronic sleep loss and lowered academic performance.