Why is this review so important?
Insomnia (difficulty falling asleep or falling asleep) is widespread, with about one in five people reporting sleep problems in the previous year. Insomnia can lead to daytime fatigue, anxiety, dysfunction during the day, and reduced quality of life. This is due to increased mental disorders, drug and alcohol abuse, and increased use of health services. Treatment depends on the duration and nature of sleep problems. It may include treatment of concomitant medical problems; advice on sleeping habits and lifestyle (so-called sleep hygiene); medication and psychotherapeutic treatments such as cognitive-behavioral therapy (CAT, which is a language therapy).
Medications are known as hypnotics (e.g. temazepam and Z-drugs [a group of non-benzodiazepines]) are more commonly used to treat insomnia and are known to improve sleep, but may have problems such as tolerance (you need to take more than one drug to get the same effect) and substance abuse (physical or mental problems when you stop taking the drug). It is recommended to use hypnotic drugs only for a short period of time (two to four weeks). However, millions of people around the world take hypnotic drugs for long periods of time.
Antidepressants are widely prescribed for insomnia, although they are not approved for this use, and evidence of their effectiveness is inconclusive. This may be due to concerns about hypnosis. Psychotherapy, such as CT, is known to help cure insomnia, but their availability is limited. For this reason, alternative drugs such as antidepressants (for the treatment of depression) and antihistamines (for the treatment of allergies) are sometimes tried. It is important to evaluate data on the unauthorized use of these drugs.
Who might be interested in this evaluation?
People with sleep disorders and their doctors will be interested in this review to better understand the study and make an informed decision about the use of antidepressants to treat insomnia.
What questions does this review try to answer?
The objective was to determine the effectiveness of antidepressants in treating insomnia in adults, their safety, and possible side effects.
What studies have we included in this review?
We have included randomized controlled trials (clinical trials in which people are randomized into two or more treatment groups; these trials provide the most reliable and qualitative data) in adults diagnosed with insomnia. These people may suffer not only from insomnia but also from other diseases (coexisting diseases). We included all doses of one antidepressant (but not related to another antidepressant) versus placebo (fake treatment), other insomnia medications (e.g. benzodiazepines or Z medications), another antidepressant, waiting list control group or “normal treatment”.
What does the evidence from this review tell us?
We have reviewed 23 trials involving 2,806 people with insomnia. The data tended to be of poor quality due to the small number of people involved and problems with the way the studies were conducted and reported. We were often unable to combine the results of individual studies. There is little evidence that antidepressants were used in the short term (i.e. weeks rather than months). There was no evidence to support amitriptyline, an antidepressant widely used in clinical practice or the long-term use of antidepressants in insomnia. The evidence does not support existing clinical practice in prescribing antidepressants for insomnia.
What happens next?
High-quality studies of antidepressants in the treatment of insomnia are necessary to obtain more convincing evidence for clinical practice. In addition, healthcare professionals and patients should be informed of the lack of evidence on antidepressants commonly used in the treatment of insomnia.