Sleep Restriction Therapy for Insomnia: What Trials Show

When you can’t sleep, the natural move is to spend longer in bed to catch whatever sleep you can. Sleep restriction therapy does the opposite: it limits the time you spend in bed, on a schedule set with a clinician. It’s a key part of CBT for insomnia.¹

The HABIT trial

CBT for insomnia is the first-line treatment, but it’s hard to get.¹ So researchers tested whether practice nurses could deliver sleep restriction on its own.

At 35 GP practices in England, 642 adults with insomnia, average age 55 and 76% women, got either:¹

• Four short sessions of sleep restriction with a nurse, plus a sleep hygiene booklet, or
• The booklet alone.

At 6 months	Insomnia severity score (lower is better)
Sleep restriction	10.91
Booklet only	13.91

The sleep restriction group had less severe insomnia, and the approach was likely to be cost-effective.¹ Serious adverse events were the same in both groups, eight each, and none were linked to the treatment.¹

The catch: the first few weeks

A small lab study followed 16 people with insomnia through 4 weeks of sleep restriction.²

• Their insomnia improved overall.²
• But in the early weeks they slept over an hour less a night on lab measurements, and felt sleepier in the daytime in weeks 1 to 3.²
• By 3 months, daytime sleepiness was back to normal.²

That’s why it’s worth doing with guidance, and why driving when drowsy is risky in the first weeks.

Which parts of CBT for insomnia matter

A review of 241 trials with 31,452 people, two-thirds of them women, tried to tease apart the pieces of CBT for insomnia.³

• Sleep restriction, stimulus control (getting up when you can’t sleep), and changing unhelpful thoughts about sleep all appeared to help.³
• Sleep hygiene education on its own wasn’t essential.³

So the booklet of tips most people are handed first is the weakest part of the package.

See what insomnia and CBT-I are, CBT for insomnia at menopause and checking the clock at night.

Try: “I’ve had insomnia for months and sleep hygiene tips haven’t helped. Is sleep restriction therapy, or full CBT for insomnia, available to me, and who could guide me through it?”

Did I Do That in My Sleep? covers this in Chapter 10, “In Bed All Night, Tired All Day,” in a section called “Getting Access,” with questions to ask about CBT-I in person, by phone or online. Its 14-Night Lights-Out Record asks for a rough morning account of bedtime, rising time and how you feel, which is what a sleep restriction schedule is built from. See the book.