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I'm only sleeping

2015; Elsevier BV; Volume: 2; Issue: 11 Linguagem: Inglês

10.1016/s2215-0366(15)00458-7

2215-0374

The Lancet Psychiatry,

Youth Substance Use and School Attendance

As with many of the good things in life, sleep is something we take for granted until we are denied our required number of hours in bed by work, travel, or a new baby. For people with mental health problems, however, poor sleep can be a common—if often neglected—issue. Science still cannot explain precisely what happens when we sleep and why we need to do so, but it is thought to be implicated in learning and the consolidation of memories. As William Golding wrote in Pincher Martin, “Sleep is when all the unsorted stuff comes flying out as from a dustbin upset in a high wind”. Disruption of this unconscious sorting process can cause more than just muddled thinking the day after a late night. Sleep disorders are both risk factors for and warning signs of mental illness. The importance of comorbidity in sleep disorders was recognised in the revision of the DSM, with DSM-5 placing greater emphasis than previous manuals on the interaction between sleep–wake disorders and other mental disorders. DSM-5 also stresses the need to treat a sleep disorder independently, whether or not other problems are present. Cognitive behavioural therapy (CBT) is established as a successful treatment for insomnia, and has been evaluated in various types of comorbid insomnia. In this issue of The Lancet Psychiatry, Daniel Freeman and colleagues report the results of the Better Sleep Trial (BeST), a pilot study assessing the first use of CBT to improve sleep in patients with persistent delusions and hallucinations. They showed that CBT effectively reduced insomnia in this population and improved other measures of sleep, such as sleep quality and the time taken to fall asleep. Unfortunately, the small size of the study precluded a decisive outcome regarding delusions and hallucinations, but the good uptake of CBT and low drop-out rates suggest that a larger trial is feasible. This study is a good example of what Max Birchwood describes as the “new wave” of CBT interventions in psychosis focusing on important comorbidity or theoretically driven treatment targets. Such trials not only provide a pragmatic approach to improving patients' quality of life, they also offer insight into the mechanisms underlying aspects of psychosis. BeST is part of a wider translational research programme that identifies a specific problem, such as sleep disruption, then compares a treatment targeting that mechanism with standard care. Sleep deprivation might be used more directly to investigate psychiatric disorders. In 1973, The Lancet published a study concerning 34 of the 55 competitors in the previous year's single-handed transatlantic yacht race. It confirmed that worse things do indeed happen at sea: namely a range of unpleasant psychological reactions—forgetfulness, errors in navigation and handling the boat, auditory, visual, and spatial hallucinations, and mood changes. A more recent study by Petrovsky and colleagues reported that healthy young volunteers deprived of sleep for 24 hours scored more highly in self ratings of perceptual distortion, anhedonia, and cognitive disorganisation. In this issue of The Lancet Psychiatry, Ulrich Ettinger and Veena Kumari propose a translational model system for use in drug development, in which experimentally controlled sleep deprivation induces key features of schizophrenia. Any model system has to have relevant, measurable parameters. Ettinger and Kumari discuss two: prepulse inhibition of the acoustic startle reflex and antisaccade eye movements. In prepulse inhibition, a weak stimulus reduces the amplitude of response to a subsequent strong stimulus; the inhibition is thought to be due to early gating processes that prevent interference from simultaneous processing of multiple stimuli. Prepulse inhibition is reduced in people with schizophrenia, but also in other psychiatric disorders, casting doubt on its specificity. The antisaccade task is a measure of cognitive control that can be tested in primates but not in common lab species, rats and mice—not because of cognitive differences but anatomical ones (these species have fixed eyeballs). Again, impairment is strongest in schizophrenia but does manifest in other psychiatric disorders. While sleep deprivation might be a helpful model for psychosis, better biomarkers are needed before it makes a useful contribution to the development of antipsychotics. Sleep has long been seen by poets and novelists as a source of inspiration. It's time for psychiatrists to follow their lead, in both clinical practice and research. The effect on quality of life might be substantial; as Lennon and McCartney pleaded in 1966: “Please don't spoil my day, I'm miles away; and after all, I'm only sleeping”. For more on the Transatlantic yacht race see Articles Lancet 1973; 302: 747–54For the study by Petrovsky et al see J Neuroscience 2014; 34: 9134–140 For more on the Transatlantic yacht race see Articles Lancet 1973; 302: 747–54 For the study by Petrovsky et al see J Neuroscience 2014; 34: 9134–140 Efficacy of cognitive behavioural therapy for sleep improvement in patients with persistent delusions and hallucinations (BEST): a prospective, assessor-blind, randomised controlled pilot trialOur findings show that CBT for insomnia might be highly effective for improving sleep in patients with persistent delusions or hallucinations. A larger, suitably powered phase 3 study is now needed to provide a precise estimate of the effects of CBT for sleep problems, both on sleep and psychotic experiences. Full-Text PDF Open AccessEffects of sleep deprivation on inhibitory biomarkers of schizophrenia: implications for drug developmentDevelopment of drugs for the treatment of the clinical symptoms and cognitive deficits of schizophrenia is unsatisfactory, with many initially promising compounds not showing beneficial effects in clinical studies. Experimental model systems of schizophrenia combined with well-validated biomarkers are urgently needed to provide early indicators of effectiveness. Herein, we argue that experimentally controlled sleep deprivation represents a translational model system that can be studied in combination with neurocognitive biomarkers. Full-Text PDF