July 29, 2005

Wake and Light Therapy for BP Depression

A new review article from a special committee from the International Society for Affective Disorders (ISAD) discusses the evidence for chronotherapeutics (light and wake therapy) in treating both unipolar and bipolar depression. The suggestions of this review article concerning the efficacy of chronotherapeutics could lead to new, larger research trials of these therapies for bipolar patients.

According to the article, about 60% of depressive patients (either bipolar or unipolar subtype) improve rapidly with sleep deprivation therapy. This can involve a single night of total sleep deprivation, or a partial (second half of the night) deprivation period. Similar numbers of positive responders to sleep deprivation therapy were also reported in a 2002 review article (Sleep Med Rev. 2002 Oct;6(5):361-77 ).

However, the dangers of sleep deprivation therapy include high reported rates of relapse, and, for bipolar patients, the possibility of induced hypo-mania or mania.

Despite this, the review from ISAD indicates that the beneficial effects of sleep deprivation therapy can be maintained through combination with daily light therapy, or certain pharmacological treatments (for bipolar patients, lithium or a serotonergic 5-HT1A autoreceptor have been used in studies with positive results).

A small but promising placebo-controlled trial from 1999 seems to corroborate this statement. In the study, 40 bipolar I subjects in a depressive episode were randomly assigned to either 3 alternating nights of total sleep deprivation (TSD) plus concurrent treatment with pindolol (a serotonergic autoreceptor blocker known to enhance the effects of SSRI antidepressants), or 3 alternate nights of total sleep deprivation (TSD) alone.

Out of the 20 subjects in each group, 75% of those treated with TSD + pindolol responded with significant improvement, as compared to 3 out of the 20 subjects undergoing only TSD. The responsive subjects were given lithium after the 11 day experimental treatment period, and there were no reports of manic episodes during the follow-up period (although one subject did relapse back into depression). The article specifically mentioned that serotonergic autoreceptors given alone have not been shown to improve depression; thus, it appears to be the effects of sleep deprivation plus the serotonergic-enhancing effects of the pindolol that caused the improvement.

Although well-designed, this was a small study, and thus the results cannot necessarily be generalized. Moreover, the dangers of sleep disturbance triggering hypomania or mania for bipolar patients has also been extensively documented; this is reported to be especially true for rapid-cyclers. The following quote from the 2002 review article of sleep deprivation (SD) therapy describes the relative risk:

"Especially in bipolar but also in unipolar depressives SD may provoke hypomanic or manic reactions...It generally subsides spontaneously and only rarely needs treatment [according to one study. Hypomanic or manic reactions after therapeutic SD amount to 11±30% in bipolar depressives and up to 65% in rapidly cycling bipolars. There are only sparse data on unipolar depressives; here the frequency is certainly 46%. For the sake of comparison, the frequency of manic reactions in the course of pharmacologic treatment of bipolar depressed patients is given: tricyclic antidepressants 11.2%, selective serotonin reuptake inhibitors (SSRI) 3.7%, placebo 4.2%. In unipolar depressives all numbers are less than 1%." (Giedke and Schwaerzler, 2002).

Other side effects of sleep deprivation reported in literature include provoked epileptic seizures (in predisposed persons), headaches, and gastrointestinal complaints.

"Despite the potential dangers, we can hope to see more studies examining the efficacy of sleep- and light-therapies for bipolar depression. The authors of the 2002 review state that, to date, "we have the impression that there are more studies in which bipolar patients respond better to SD [sleep deprivation] than unipolars do..." (Giedke and Schwaerzler, 2002)

It seems that chronotherapeutics, if their benefits can be stabilized and maintained, may have the potential to help treat the notoriously difficult problem of bipolar depression.

Note: Please do not try any sort of sleep-deprivation therapy, or any other new treatment, without proper medical supervision. The potential for sleep disturbance to trigger mania has been well-documented; until chronotherapeutics for bipolar patients is better understood, we do not recommend attempting this treatment without specific advisement and supervision of your doctor.

Sources for this article:

Chronotherapeutics (light and wake therapy) in affective disorders.
Psychol Med. 2005 Jul;35(7):939-44.

Therapeutic use of sleep deprivation in depression.
Sleep Med Rev. 2002 Oct;6(5):361-77. Review.

Sustained antidepressant effect of sleep deprivation combined with pindolol in bipolar depression. A placebo-controlled trial.
Neuropsychopharmacology. 1999 Apr;20(4):380-5.

Comments

Post a comment


Type the characters you see in the picture above.

Remember Me?