SRT (Sleep Restriction Therapy) – Get out of bed if you’re not asleep!
The concept of sleep restrictions is to restrict the time in bed to sleep only. Go to bed when tired, get out of bed if you cannot sleep.
Sometimes when someone cannot sleep, they go to bed earlier and try harder to sleep. One problem that occurs is the harder you try to sleep the more difficult it becomes. So where it may seem intuitive to go to bed earlier to sleep earlier, it is counter productive because you are not sleeping anyway and now you begin to develop frustrations about not sleeping.
SRT origins are from studies of partial sleep deprivation and chronobiology. The rationale for SRT includes the 3P model of insomnia emphasizing the Perpetuating activities. The procedure of initially restricting time in bed with gradual increases assures that sleep drive will be heightened at the start of treatment.
In early sleep deprivation experiments it was clear that return to sleep lead to more efficient sleep. There was less stage 1 light sleep and more deep SWS (Slow-Wave Sleep).
It was also noted that people with emotional distress that were prone to internalization had more insomnia. This insomnia lead to anticipatory anxiety about not sleeping, leading to more insomnia. – People with internalizing personality, if they worry about insomnia, it becomes a self fulfilling prophecy.
Drug therapy has its limits. Longer acting agents such as Benzodiazepine hypnotics can cause hangover, early morning awakenings, morning anxiety, rebound anxiety, tolerance, moodiness, memory problems. However shorter acting agents such as Non-Benzodiazepine hypnotics do not last through the night and can also cause similar symptoms. Both however, or to say neither, address the etiology of the sleep problem. So eventually when tolerance occurs, difficulty getting to sleep even on the medications occurs. If you take a med for sleep, but you are not asleep, that is when several side effects will be felt.
At first when you speak with patients about SRT (Sleep Restriction Therapy) it seems counterintuitive. They feel they need more sleep and you are advising they spend less time in bed. If there is a heightened sleep drive with partial sleep restriction, this leads to a rapid sleep onset, consolidated sleep, deeper sleep. Ask a patient with insomnia if they had recovery sleep following really bad nights.
Reducing TIB (Time In Bed) addresses factors that perpetuate insomnia:
– Allows for more predictable sleep. There are less very poor or very good nights. Reduces anticipatory anxiety over what each night will bring. Sleep becomes more unstable. They stop “wondering” how the night will go. Effect is nearly immediate.
– Less time spent tossing and turning in bed. Repairs the broken association between the bed and sleep, reduces the “I cannot sleep”.
– More consistently timed sleep rebuilds an attenuated circadian sleep/wake cycle. Getting up the same time everyday, helps reinforce and rebuild circadian cues. Reduces sleeping in late on weekends (miss window for early light causing phase delay), reduces really early awakenings (builds homeostatic drive and causes phase advance).
– SRT focuses on fixing the perpetuating factor.
– Price to pay for reliable and good quality sleep is daytime fatigue, sleepiness, performance deficits.
– Side benefit of experiencing sleepiness, “my sleep system still works”. Means there sleep wake regulation system is not broken.
– Assurance that as TIB is increased, daytime deficits will diminish.
– Spending more TIB is an ill-conceived strategy.
– It strengthens circadian cues.
– What time a person gets into bed is one aspect where people with insomnia “have control”.
– Improves the experience of going to bed. Less worry about surprises as there will be less “good and bad” nights.
– EDS (Excessive Daytime Sleepiness) is an initial side effect, though it is what helps one get to sleep earlier the next day.
– SRT is not recommended to individuals whose sleep is already compact.
– Not effective when there is an untreated depression.
– SRT in patients with paradoxical insomnia, rules for increasing time in bed do not work well.
– Some older individuals may have limits to their capacity to consolidate sleep.
– Never take below 5 hours or 4 hours in bed.
– Determine average time asleep from sleep diary.
– Set time in bed + average time asleep from sleep diary
– Set a consistent wake-up time
– No daytime naps
– If 5 day average sleep efficiency >90% then increase time in bed by 15-30 minutes
– If 5 day average sleep efficiency is <85% then decrease time in bed by 15-30 minutes
However, this is one technique that I do not advise that a person calculate their own formula. I highly advise that Sleep Restriction be conducted under supervision of a member of the Society of Behavioral Sleep Medicine.