Sleep dysfunction and the occurrence of delusions and hallucinations
Freeman, D et al. (2015). Efficacy of cognitive behavioural therapy for sleep improvement in patients with persistent delusions and hallucinations (BEST): a prospective, assessor-blind, randomised controlled pilot trial. Lancet Psychiatry (2015(2)), 975-983.
This review incorporated multiple investigations with regards to sleep and psychotic experience in both healthy and psychiatric populations (including the article from part 1). Included research was quite broad looking at sleep dysfunction as a whole, although particular evidence surrounding insomnia and paranoia associated with psychotic experiences was fairly interesting across both populations.
Following the review of the literature the findings support the co-existence of sleep dysfunction and psychotic experiences, most significantly with chronic insomnia and paranoia. An interesting finding within this research was insomniacs with concomitant paranoia were five times more likely to suffer from persecutory delusions. Severe delusions such as these were correlated with comorbid mental health symptoms or substance abuse, but were evident in healthy samples when controlling for these variables.
Cross-sectional research included in the current review indicated that insomnia was an accurate predictor of increased paranoia manifesting as delusions, hallucinations or cognitive disorganisation. A number of factors have been theorised as to the mechanistic action which promotes instances of psychotic experiences or more specifically paranoia in insomniac patients. Significant relationships were identified with a genetic and environmental model demonstrating an “aetiological overlap”, as well as partial evidence indicating depression and anxiety may facilitate the paranoia responses seen with insomnia. The strongest evidence supporting the associations of insomnia with paranoia occurred within healthy populations, although promising correlations were demonstrated by clinical populations, assessment of psychotic experiences in this population were limited and therefore inconclusive compared to healthy individuals.
Cognitive Behavioural Therapy to treat insomnia in Schizophrenic patients suffering from delusions and hallucinations.
Reeve, S, Sheaves, B & Freeman, D. (2015). The role of sleep dysfunction in the occurrence of delusions and hallucinations: a systematic review. Clinical Psychology Review (42) 2015, 96-115.
Delusions and hallucinations often suffered by schizophrenic patients have demonstrated a significant association with sleep disorders. Schizophrenia patients whom report the incidence of persecutory delusions have the highest comorbidity with sleep disorders, particularly insomnia with 54% of those with this delusional subtype diagnosed with clinical insomnia. Cognitive behavioural therapy (CBT) has previously indicated its potential to promote the reduction of paranoia in healthy individuals and is the recommended treatment for this population, however this is yet to be validated for treating coexisting insomnia and schizophrenia with the goal of eradicating delusions and hallucinations.
This study implemented a CBT intervention for schizophrenia patients whom scored >15 on the Insomnia Severity Index and did not possess a primary sleep disorder. CBT involved eight sessions of twelve weeks focusing on psycho-education and sleep hygiene among other simplified therapeutic techniques. The aim of this intervention was improve the severity of insomnia with concurrent reductions of delusions and hallucinations. Following twelve weeks of CBT, 41% of patients demonstrated significant improvements in insomnia severity (<15), although changes to delusions and hallucinations were unclear with a range of psychotic experiences noted at the conclusion of the intervention.
CBT in this study demonstrates promise for improving insomnia severity as well as improvements in fatigue and well-being as reported by participants. In terms of psychotic experiences, the evidence obtained is inconclusive to affirm the effects of CBT had to minimise hallucinations and delusions in schizophrenic populations. It was also noted that this research was “insufficiently powered to detect anything but the largest effect sizes.”
