Antidepressants for insomnia in adults.

BACKGROUND: Insomnia disorder is a subjective condition of unsatisfactory sleep (e.g. sleep onset, maintenance, early waking, impairment of daytime functioning). Insomnia disorder impairs quality of life and is associated with an increased risk of physical and mental health problems including anxiety, depression, drug and alcohol abuse, and increased health service use. hypnotic medications (e.g. benzodiazepines and 'Z' drugs) are licensed for sleep promotion, but can induce tolerance and dependence, although many people remain on long-term treatment. Antidepressant use for insomnia is widespread, but none is licensed for insomnia and the evidence for their efficacy is unclear. This use of unlicensed medications may be driven by concern over longer-term use of hypnotics and the limited availability of psychological treatments. OBJECTIVES: To assess the effectiveness, safety and tolerability of antidepressants for insomnia in adults. SEARCH METHODS: This review incorporated the results of searches to July 2015 conducted on electronic bibliographic databases: the Cochrane Central Register of Controlled Trials (CENTRAL, 2015, Issue 6), MEDLINE (1950 to 2015), Embase (1980 to 2015) and PsycINFO (1806 to 2015). We updated the searches to December 2017, but these results have not yet been incorporated into the review. SELECTION CRITERIA: Randomised controlled trials (RCTs) of adults (aged 18 years or older) with a primary diagnosis of insomnia and all participant types including people with comorbidities. Any antidepressant as monotherapy at any dose whether compared with placebo, other medications for insomnia (e.g. benzodiazepines and 'Z' drugs), a different antidepressant, waiting list control or treatment as usual. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for eligibility and extracted data using a data extraction form. A third review author resolved disagreements on inclusion or data extraction. MAIN RESULTS: The search identified 23 RCTs (2806 participants).Selective serotonin reuptake inhibitors (SSRIs) compared with placebo: three studies (135 participants) compared SSRIs with placebo. Combining results was not possible. Two paroxetine studies showed significant improvements in subjective sleep measures at six (60 participants, P = 0.03) and 12 weeks (27 participants, P < 0.001). There was no difference in the fluoxetine study (low quality evidence).There were either no adverse events or they were not reported (very low quality evidence).Tricyclic antidepressants (TCA) compared with placebo: six studies (812 participants) compared TCA with placebo; five used doxepin and one used trimipramine. We found no studies of amitriptyline. Four studies (518 participants) could be pooled, showing a moderate improvement in subjective sleep quality over placebo (standardised mean difference (SMD) -0.39, 95% confidence interval (CI) -0.56 to -0.21) (moderate quality evidence). Moderate quality evidence suggested that TCAs possibly improved sleep efficiency (mean difference (MD) 6.29 percentage points, 95% CI 3.17 to 9.41; 4 studies; 510 participants) and increased sleep time (MD 22.88 minutes, 95% CI 13.17 to 32.59; 4 studies; 510 participants). There may have been little or no impact on sleep latency (MD -4.27 minutes, 95% CI -9.01 to 0.48; 4 studies; 510 participants).There may have been little or no difference in adverse events between TCAs and placebo (risk ratio (RR) 1.02, 95% CI 0.86 to 1.21; 6 studies; 812 participants) (low quality evidence).'Other' antidepressants with placebo: eight studies compared other antidepressants with placebo (one used mianserin and seven used trazodone). Three studies (370 participants) of trazodone could be pooled, indicating a moderate improvement in subjective sleep outcomes over placebo (SMD -0.34, 95% CI -0.66 to -0.02). Two studies of trazodone measured polysomnography and found little or no difference in sleep efficiency (MD 1.38 percentage points, 95% CI -2.87 to 5.63; 169 participants) (low quality evidence).There was low quality evidence from two studies of more adverse effects with trazodone than placebo (i.e. morning grogginess, increased dry mouth and thirst). AUTHORS' CONCLUSIONS: We identified relatively few, mostly small studies with short-term follow-up and design limitations. The effects of SSRIs compared with placebo are uncertain with too few studies to draw clear conclusions. There may be a small improvement in sleep quality with short-term use of low-dose doxepin and trazodone compared with placebo. The tolerability and safety of antidepressants for insomnia is uncertain due to limited reporting of adverse events. There was no evidence for amitriptyline (despite common use in clinical practice) or for long-term antidepressant use for insomnia. High-quality trials of antidepressants for insomnia are needed.

Neural correlates of the psychedelic state as determined by fMRI studies with psilocybin.

Psychedelic drugs have a long history of use in healing ceremonies, but despite renewed interest in their therapeutic potential, we continue to know very little about how they work in the brain. Here we used psilocybin, a classic psychedelic found in magic mushrooms, and a task-free functional MRI (fMRI) protocol designed to capture the transition from normal waking consciousness to the psychedelic state. Arterial spin labeling perfusion and blood-oxygen level-dependent (BOLD) fMRI were used to map cerebral blood flow and changes in venous oxygenation before and after intravenous infusions of placebo and psilocybin. Fifteen healthy volunteers were scanned with arterial spin labeling and a separate 15 with BOLD. As predicted, profound changes in consciousness were observed after psilocybin, but surprisingly, only decreases in cerebral blood flow and BOLD signal were seen, and these were maximal in hub regions, such as the thalamus and anterior and posterior cingulate cortex (ACC and PCC). Decreased activity in the ACC/medial prefrontal cortex (mPFC) was a consistent finding and the magnitude of this decrease predicted the intensity of the subjective effects. Based on these results, a seed-based pharmaco-physiological interaction/functional connectivity analysis was performed using a medial prefrontal seed. Psilocybin caused a significant decrease in the positive coupling between the mPFC and PCC. These results strongly imply that the subjective effects of psychedelic drugs are caused by decreased activity and connectivity in the brain's key connector hubs, enabling a state of unconstrained cognition.

Mourning and melancholia revisited: correspondences between principles of Freudian metapsychology and empirical findings in neuropsychiatry.

Freud began his career as a neurologist studying the anatomy and physiology of the nervous system, but it was his later work in psychology that would secure his place in history. This paper draws attention to consistencies between physiological processes identified by modern clinical research and psychological processes described by Freud, with a special emphasis on his famous paper on depression entitled 'Mourning and melancholia'. Inspired by neuroimaging findings in depression and deep brain stimulation for treatment resistant depression, some preliminary physiological correlates are proposed for a number of key psychoanalytic processes. Specifically, activation of the subgenual cingulate is discussed in relation to repression and the default mode network is discussed in relation to the ego. If these correlates are found to be reliable, this may have implications for the manner in which psychoanalysis is viewed by the wider psychological and psychiatric communities.

The role of emission tomography in pharmacokinetic and pharmacodynamic studies in clinical psychopharmacology.

Position Emission Tomography (PET) and Single Photon Emission Tomography (SPECT) can be used for both pharmacokinetic and pharmacodynamic measures in vivo in man. As such they have a wide range of applications including description of neurochemical changes in disease, occupancy, brain effects of medicines and discovery and validation of biomarkers. The power of these tools is in their chemical specificity and sensitivity, and in the ability to describe processes in vivo, thus documenting the effects of genetic and environmental interactions. The future of these technologies is dependent on an investment in bringing out and validating new radiotracers.

Structural and functional brain changes in posttraumatic stress disorder.

Posttraumatic stress disorder (PTSD) is a highly disabling condition that is associated with intrusive recollections of a traumatic event, hyperarousal, avoidance of clues associated with the trauma, and psychological numbing. The field of neuroimaging has made tremendous advances in the past decade and has contributed greatly to our understanding of the physiology of fear and the pathophysiology of PTSD. Neuroimaging studies have demonstrated significant neurobiologic changes in PTSD. There appear to be 3 areas of the brain that are different in patients with PTSD compared with those in control subjects: the hippocampus, the amygdala, and the medial frontal cortex. The amygdala appears to be hyperreactive to trauma-related stimuli. The hallmark symptoms of PTSD, including exaggerated startle response and flashbacks, may be related to a failure of higher brain regions (i.e., the hippocampus and the medial frontal cortex) to dampen the exaggerated symptoms of arousal and distress that are mediated through the amygdala in response to reminders of the traumatic event. The findings of structural and functional neuroimaging studies of PTSD are reviewed as they relate to our current understanding of the pathophysiology of this disorder.

Naloxone displacement at opioid receptor sites measured in vivo in the human brain.

We report the use of a sensitive non-tomographic positron detecting system to measure the dose-response curve of naloxone in human brain. [11C]Diprenorphine was administered to normal volunteers in tracer amounts and, 30 min later, various bolus doses of naloxone were given (1.5-160 microg/kg) intravenously and change in [11C]diprenorphine binding monitored over the next 30 min. We found that this method produced results consistent with existing data. It was observed that approximately 13 microg/kg of naloxone ( approximately 1 mg in an 80 kg man) was required to produce an estimated 50% receptor occupation. This is consistent with the clinical dose of naloxone used to reverse opiate overdose (0.4 mg-1.2 mg).

Receptor binding and drug modulation in anxiety.

Anxiety is an emotion that allows an individual to prepare for, or respond to, changes in the environment. For many people, however, this emotion is expressed inappropriately and impairs their lives causing considerable distress and disability. These disorders cause a great deal of personal distress, result in reduced life expectancy and, in the UK alone, have an estimated cost of approximately pound 5 billion per year. Despite a great deal of research, an adequate account of the mechanisms that underlie these human disorders is still lacking. An understanding of the brain substrates underlying these disorders is likely to provide such adequate explanations, but one of the principal challenges facing the investigators has been the reciprocal mapping of pre-clinical and clinical knowledge. Altogether, the last 10 years have seen a consolidation of imaging techniques. These are now mature in many areas and are likely to provide fundamental contributions in our understanding of human psychopharmacology.

Modulation of ion channels in clinical psychopharmacology: adults and younger people.

This review focuses on the use of Na(+), Ca(2+) and Cl(-) channel modulators in psychiatric disease. Drugs that modulate ion channels have been used in psychiatry for more than a century, and in this review we critically evaluate clinical research that reports the therapeutic effects of drugs acting on GABA(A), voltage-gated Na(+) and voltage-gated Ca(2+) channels in pediatric and adult patients. As in other fields, the evidence underpinning the use of medicines in younger people is far less robust than for adults. In addition, we discuss some current developments and highlight clinical disorders in which current molecules could be further tested. Notable success stories, such as benzodiazepines (in sleep and anxiety disorders) and antiepileptics (in bipolar disorder), have been the result of serendipitous discoveries or refinements of serendipitous discoveries, as in all other major treatments in psychiatry. Genomic, high-throughput screening and molecular pharmacology discoveries may, however, guide further developments in the future. This could include increased research in promising targets that have been perceived as commercially risky, such as selective α-subunit GABA(A) receptors.

Using [11C]diprenorphine to image opioid receptor occupancy by methadone in opioid addiction: clinical and preclinical studies.

Substitute methadone prescribing is one of the main modes of treatment for opioid dependence with established evidence for improved health and social outcomes. However, the pharmacology underpinning the effects of methadone is little studied despite controversies about dosing in relation to outcome. We therefore examined the relationship between methadone dose and occupation of opioid receptors in brain using the positron emission tomography (PET) radioligand [(11)C]diprenorphine in humans and rats. Eight opioid-dependent subjects stable on their substitute methadone (18-90 mg daily) had an [(11)C]diprenorphine PET scan at predicted peak plasma levels of methadone. These were compared with eight healthy controls. No difference in [(11)C]diprenorphine binding was found between the groups, with no relationship between methadone dose and occupancy. Adult male Sprague-Dawley rats that had been given an acute i.v. injection of methadone hydrochloride (0.35, 0.5, 0.7, or 1.0 mg kg(-1)) before [(11)C]diprenorphine showed a dose-dependent increase in biodistribution but no reduction in [(11)C]diprenorphine binding. We suggest that the lack of a dose-dependent relationship between methadone dose, either given chronically in human or acutely in rat, and occupancy of opioid receptor measured with [(11)C]diprenorphine PET is related to efficacy of this opioid agonist at very low levels of opioid receptor occupancy. This has implications for understanding the actions of methadone in comparison with other opioid drugs such as partial agonists and antagonists.

Functional connectivity analysis of the neural circuits of opiate craving: "more" rather than "different"?

We investigated the functional connectivity of brain regions activated during opiate craving. Previously we used recorded autobiographical scripts to induce opiate craving in 12 abstinent opiate-dependent subjects while they were undergoing positron emission tomography (PET) scanning using the regional cerebral blood flow (rCBF) tracer H2 15O. SPM99 was used to examine the connectivity patterns associated with the primary brain regions activated in response to drug-craving memories (anterior cingulate, AC) and correlated with opiate craving (orbitofrontal cortex, OFC). Two separate connectivity patterns were identified associated with the OFC and AC regions. The AC region was associated with activity in the left temporal region. The left OFC region activity correlated with activity in the right OFC, and left parietal and posterior insular regions. There was also a positive association with the hippocampus and brainstem. Both the AC and OFC regions showed a negative association with posterior visual areas. We suggest that the patterns of functional connectivity reflect the ability of drug-related stimuli to activate attentional and memory circuits to a greater degree than non-drug-related stimuli. This argues that neural circuits of dependence and craving are not specific "craving" or "addiction" brain regions but are "normal" circuits activated to a greater degree.