Sleep Interruptions Worse than Insufficient Sleep, Research Finds

Sharon Moore November 11, 2015

Researchers from Johns Hopkins Medicine found that sleep interruptions had far greater risks on mental health than insufficient sleep without interruption.

The new study involved 62 healthy men and women randomly subjected to three sleep experimental conditions in an inpatient clinical research suite. The participants had three consecutive nights of either forced awakenings, delayed bedtimes or uninterrupted sleep. Then, all of them were asked to rate how strongly they felt a variety of positive and negative emotions, such as cheerfulness or anger the following day.

Participants whose sleep was interrupted and those with delayed bedtimes showed similar low positive mood and high negative mood after the first night.

But significant differences emerged after the second night, according to the researchers. Those whose sleep was interrupted had a 31 per cent reduction in positive mood, while those who had delayed bedtime has a decline of 12 per cent compared to the first day. The researchers didn’t find significant differences in negative mood between the two groups on any of the three days, which suggests that sleep fragmentation is especially detrimental to positive mood.

And even though the study was conducted on healthy subjects with generally normal sleep experiences, the researchers say that the result is likely to apply to those who suffer from insomnia.

"When your sleep is disrupted throughout the night, you don’t have the opportunity to progress through the sleep stages to get the amount of slow-wave sleep that is key to the feeling of restoration," according to Patrick Finan, Ph.D., lead author of the study and an assistant professor of psychiatry and behavioural sciences at the Johns Hopkins University School of Medicine.

He adds that frequent awakenings is one of the most common symptoms among people with insomnia.

"Many individuals with insomnia achieve sleep in fits and starts throughout the night, and they don’t have the experience of restorative sleep,"

In the study, those who had frequent sleep interruptions demonstrated shorter periods of deep, slow-wave sleep which is associated to positive mood.

The researchers found that interrupted sleep affected different domains of positive mood; it reduced not only energy levels, but also feelings of sympathy and friendliness.

The study was published in the journal Sleep.

Source of this article

Sleep