Psychotherapeutic benefits of opioid agonist therapy

The Link between Depression and Chronic Pain: Neural Mechanisms in the Brain

Chronic pain, as a stress state, is one of the critical factors for determining depression, and their coexistence tends to further aggravate the severity of both disorders. Unfortunately, their association remains unclear, which creates a bottleneck problem for managing chronic pain-induced depression. In recent years, studies have found considerable overlaps between pain- and depression-induced neuroplasticity changes and neurobiological mechanism changes. Such overlaps are vital to facilitating the occurrence and development of chronic pain and chronic pain-induced depression. In this review, we summarized the role of neuroplasticity in the occurrence and development of the two disorders in question and explored individualized application strategies of analgesic drugs and antidepressants that have different pharmacological effects in the treatment of chronic pain-induced depression. Therefore, this review may provide new insights into the understanding of association between chronic pain and depression.

Use of Buprenorphine in treatment of refractory depression-A review of current literature

OBJECTIVE

Current treatment strategies for depressive disorders have limited efficacy, leaving many patients unimproved or with significant residual symptoms. The development of additional treatments represent a significant unmet need for providers. Several lines of evidence suggest that the opioid system may be involved in regulation of mood and incentives salience. Intervention based on modifying central opioid receptors may represent a novel approach to treatment of depressive disorders among those unresponsive to accepted treatments.

DATA SOURCES

We searched the English language literature using keywords: Buprenorphine AND Major Depression; Buprenorphine AND Bipolar Depression; Buprenorphine AND Affective Disorders.

RESULTS

Use of low dose buprenorphine as augmentation of pharmacotherapy for depression has shown promise in several reported studies. Effect size of available randomized controlled studies is comparable if not greater than most accepted augmentation strategies.

CONCLUSION

Review of available literature on the use of buprenorphine in individuals with treatment resistant depression demonstrated efficacy in the treatment of depressive disorders. Further prospective randomized controlled trials should be undertaken to evaluate the efficacy of buprenorphine as an adjunct for depression refractory to current pharmacotherapies.

Hospitalized opioid-dependent patients: Exploring predictors of buprenorphine treatment entry and retention after discharge

OBJECTIVES

Few studies have explored predictors of entry into and retention in buprenorphine treatment following linkage from an acute medical hospitalization.

METHODS

This secondary analysis of a completed clinical trial focuses on medically hospitalized, opioid-dependent patients (n = 72) who were randomized to an intervention including buprenorphine induction and dose stabilization during hospitalization followed by post-discharge transition to office-based buprenorphine treatment (OBOT). Predictors included demographics, days hospitalized, prior buprenorphine/methadone treatment, PTSD symptoms, social support, and readiness for drug use cessation. Outcome variables were treatment entry and retention (number of days in OBOT).

RESULTS

Previous buprenorphine treatment, more days hospitalized, and higher PTSD symptoms predicted OBOT entry. Prior treatment, older age, and non-minority status were associated with a higher mean number of days in OBOT.

CONCLUSIONS

OBOT may appeal to patients who have tried buprenorphine in other settings. Linking hospitalized patients to OBOT may improve utilization of addiction treatment.

SCIENTIFIC SIGNIFICANCE

Prior substance treatment, longer hospital stay, and mental health should be examined in future linkage studies. (Am J Addict 2017;26:667-672).

The Psycho-Neurology of Cross-Species Affective/Social Neuroscience: Understanding Animal Affective States as a Guide to Development of Novel Psychiatric Treatments

During the past half century of research with preclinical animal models, affective neuroscience has helped identify and illuminate the functional neuroanatomies and neurochemistries of seven primary process, i.e., genetically provided emotional systems of mammalian brains. All are subcortically localized, allowing animal models to guide the needed behavioral and neuroscientific analyses at levels of detail that cannot be achieved through human research, including modern brain imaging. They consist of the following neuronal processes: SEEKING/Enthusiasm, RAGE/Anger, FEAR/Anxiety, sexual LUST/Passion, maternal CARE/Nurturance, separation-distress PANIC/Grief and PLAY/Social Joy. Several of these systems figure heavily in social bonding. I will focus here especially on the genesis of depression. Its genesis is significantly influenced by (i) sustained overactivity of the separation-distress PANIC system reflecting severed social bonds and the excessive "psychological pain" of loneliness that can, if sustained, lead to a downward cascade known as psychological despair, and (ii) the despair phase that follows the acute PANIC response, which is characterized by abnormally low activity of the SEEKING, the so-called brain reward networks, leading to amotivational states that characterize depression. Depressive affect is promoted by such brain affective mechanisms of social attachments and social loss as well as diminished arousability of the SEEKING system, leading to chronic dysphoria. To understand why depression feels so bad, we must understand the neural mechanisms that mediate such social feelings.

Affective preclinical modeling of psychiatric disorders: taking imbalanced primal emotional feelings of animals seriously in our search for novel antidepressants

Preclinical animal models of psychiatric disorders are of critical importance for advances in development of new psychiatric medicine. Regrettably, behavior-only models have yielded no novel targeted treatments during the past half-century of vigorous deployment. This may reflect the general neglect of experiential aspects of animal emotions, since affective mental states of animals supposedly cannot be empirically monitored. This supposition is wrong—to the extent that the rewarding and punishing aspects of emotion circuit arousals reflect positive and negative affective states. During the past decade, the use of such affective neuroscience-based animal modeling has yielded three novel antidepressants (i) via the alleviation of psychic pain with low doses of buprenorphine; (ii) via the amplification of enthusiasm by direct stimulation of the medial forebrain bundle); and (iii) via the facilitation of the capacity for social joy with play facilitators such as rapastinel (GLYX13). All have progressed to successful human testing. For optimal progress, it may be useful for preclinical investigators to focus on the evolved affective foundations of psychiatrically relevant brain emotional disorders for optimal animal modeling.

Medications between psychiatric and addictive disorders

INTRODUCTION

Many epidemiological studies have revealed a frequent co-occurrence of psychiatric and substance use disorders. The term used in the literature to refer to this co-occurrence is dual diagnosis. The high prevalence of dual diagnosis has led physicians to observe the effects of medication prescribed to treat psychiatric disorders on the co-occurring substance use disorder and vice versa. The concept of medications between psychiatric and addictive disorders stems from these clinical observations, alongside which, however, it has developed from the observation that both psychiatric and substance use disorders share common neurobiological pathways and trigger common cognitive disorders. This has led researchers to develop medications on the basis of neurobiological and cognitive rationales.

MATERIAL AND METHOD

In our article, we review peculiar medications based on neurobiological and cognitive rationales and that have an impact in both psychiatric and addictive disorders.

RESULTS

We highlight how interesting these new prescriptions are for clinical observation and for the treatment of patients suffering from dual diagnosis.

CONCLUSION

We then go on to discuss the interest in them from the perspective of clinical practice and clinical research, in that the development of medications to treat dual diagnosis helps to further our knowledge of both psychiatric and substance use disorders.

A Possible Role of Anhedonia as Common Substrate for Depression and Anxiety

Depression and anxiety are often comorbid, in up to 70% of cases, and the level of one or the other may fluctuate, leading now to a diagnosis of depression, now to a diagnosis of anxiety. For these reasons, and for the presence of many other common factors, it has been suggested that both are part of the same continuum of problems and that they have a common substrate. This paper proposes the possibility that anhedonia may be an important component of this possible common substrate, and it tries to identify the mechanism with which anhedonia could contribute to causing both depression and anxiety. It also proposes an explanation why an intense pleasure could improve both depression and anxiety.

Operationalizing Pain Treatment in the Biopsychosocial Model: Take a Daily "SWEM"--Socialize, Work, Exercise, Meditate

In the United States, chronic pain is often poorly treated at an exceedingly high cost. The use of the biomedical model to manage pain is frequently ineffective, and evidence suggests that the biopsychosocial (BPS) model is a better choice. A problem with the BPS model is that it has not been operationalized in terms of patient behavior. This commentary addresses that issue by suggesting that people with chronic pain and illness participate daily in four self-management health behaviors: socialize, work, exercise, and meditation, and discusses evidence that supports these recommendations. These self-management behaviors may decrease pain and thus reduce the need for pain medications and other medical interventions. Additional topics include patient adherence and health coaching.

Development of New Psychopharmacological Agents for Depression and Anxiety

Antidepressant and anxiolytic drug development has largely stalled. This article reviews novel current programs for developing depressants and anxiolytics. Biological bases are discussed for these, as are recent results. Problems encountered are reviewed. Recently announced failed programs for other antidepressants are then discussed with an eye toward uncovering possible common elements that may explain their failures. Lastly, possible solutions for improving the likelihood of the success of antidepressant/anxiolytic agents are discussed.

Evaluation of opioid modulation in major depressive disorder

Although opioids have known antidepressant activity, their use in major depressive disorder (MDD) has been greatly limited by risk of abuse and addiction. Our aim was to determine whether opioid modulation achieved through a combination of a μ-opioid partial agonist, buprenorphine (BUP), and a potent μ-opioid antagonist, samidorphan (SAM), would demonstrate antidepressant activity without addictive potential. A placebo-controlled crossover study assessed the opioid pharmacodynamic profile following escalating doses of SAM co-administered with BUP in opioid-experienced adults. A subsequent 1-week, placebo-controlled, parallel-group study was conducted in subjects with MDD and an inadequate response to standard antidepressant therapy. This second study evaluated safety and efficacy of ratios of BUP/SAM that were associated with partial and with maximal blockade of opioid responses in the initial study. Pupillometry, visual analog scale assessments, and self-reported questionnaires demonstrated that increasing amounts of SAM added to a fixed dose of BUP resulted in dose-dependent reductions in objective and subjective opioid effects, including euphoria and drug liking, in opioid-experienced adults. Following 7 days of treatment in subjects with MDD, a 1 : 1 ratio of BUP and SAM, the ratio associated with maximal antagonism of opioid effects, exhibited statistically significant improvement vs placebo in HAM-D17 total score (p=0.032) and nearly significant improvement in Montgomery-Åsberg Depression Rating Scale (MADRS) total score (p=0.054). Overall, BUP/SAM therapy was well tolerated. A combination of BUP and SAM showed antidepressant activity in subjects with MDD. Balanced agonist-antagonist opioid modulation represents a novel and potentially clinically important approach to the treatment of MDD and other psychiatric disorders.

Effects of buprenorphine on behavioral tests for antidepressant and anxiolytic drugs in mice

RATIONALE

Buprenorphine (BPN) has been shown to rapidly improve mood in treatment-resistant depressed patients in small clinical studies. However, BPN's effects in preclinical tests for mood and antidepressant efficacy are largely unexplored.

OBJECTIVE

The current study examined the effects of BPN in the forced swim test (FST) and novelty-induced hypophagia (NIH) test as measures of antidepressant and anxiolytic-like effects in C57BL/6 J mice. Microdialysis was used to measure whether BPN engaged kappa-opioid receptor (KORs) in the nucleus accumbens shell (NAcSh) at a behaviorally active dose (0.25 mg/kg).

METHODS

BPN was tested in the FST at both 30 min and 24 h post-administration. Also measured in the FST at 24 h post-administration were the KOR antagonist norbinaltorphimine (nor-BNI), the MOR agonist morphine and the reference antidepressant desipramine. The anxiolytic effects of BPN were examined in the NIH test 24 h after treatment. The effects of acute injection of BPN and the KOR agonist U50,488 were measured on extracellular dopamine (DA) levels in the NAcSh.

RESULTS

BPN produced significant reductions in FST immobility without changing locomotor activity and reduced approach latencies in the novel environment of the NIH test when tested 24 h after treatment. Repeated daily BPN injections for 6 days did not produce tolerance to these behavioral effects. nor-BNI produced a similar antidepressant-like response in the FST 24 h post-injection but morphine and desipramine were ineffective. BPN (0.25 mg/kg) did not alter DA levels when given alone but prevented the KOR agonist U50,488 from reducing DA levels.

CONCLUSIONS

Acute and subchronic treatment with BPN produced antidepressant and anxiolytic-like responses in mice at doses that engage KORs. These studies support the clinical evidence that BPN may be a novel rapid-acting antidepressant medication and provides rodent models for investigating associated neurochemical mechanisms.

Test-retest reproducibility of binding parameters in humans with 11C-LY2795050, an antagonist PET radiotracer for the κ opioid receptor

(11)C-LY2795050 is a new antagonist PET radioligand for the κ opioid receptor (KOR). In this study, we assessed the reproducibility of the binding parameters of (11)C-LY2795050 in healthy human subjects.

METHODS

Sixteen healthy subjects (11 men and 5 women) underwent 2 separate 90-min PET scans with arterial input function and plasma free fraction (fP) measurements. The 2-tissue-compartment model and multilinear analysis-1 were applied to calculate 5 outcome measures in 14 brain regions: distribution volume (VT), VT normalized by fP (VT/fP), and 3 binding potentials (nondisplaceable binding potential, binding potential relative to total plasma concentration, and binding potential relative to free plasma concentration: BPND, BPP, BPF, respectively). Since KOR is distributed ubiquitously throughout the brain, there are no suitable reference regions. We used a fixed fraction of individual cerebellar VT value (VT,CER) as the nondisplaceable VT (VND) (VND = VT,CER/1.17). The relative and absolute test-retest variability and intraclass correlation coefficient were evaluated for the outcome measures of (11)C-LY2795050.

RESULTS

The test-retest variability of (11)C-LY2795050 for VT was no more than 10% in any region and was 12% in the amygdala. For binding potential (BPND and BPP), the test-retest variability was good in regions of moderate and high KOR density (BPND > 0.4) and poor in regions of low density. Correction by fP (VT/fP or BPF) did not improve the test-retest performance.

CONCLUSION

Our results suggest that quantification of (11)C-LY2795050 imaging is reproducible and reliable in regions with moderate and high KOR density. Therefore, we conclude that this first antagonist radiotracer is highly useful for PET studies of KOR.

Beyond Monoamines-Novel Targets for Treatment-Resistant Depression: A Comprehensive Review

Major depressive disorder (MDD) is a leading cause of disability worldwide. Current first line therapies target modulation of the monoamine system. A large variety of agents are currently available that effectively alter monoamine levels; however, approximately one third of MDD patients remain treatment refractory after adequate trials of multiple monoamine based therapies. Therefore, patients with treatment-resistant depression (TRD) may require modulation of pathways outside of the classic monoamine system. The purpose of this review was thus to discuss novel targets for TRD, to describe their potential mechanisms of action, the available clinical evidence for these targets, the limitations of available evidence as well as future research directions. Several alternate pathways involved in the patho-etiology of TRD have been uncovered including the following: inflammatory pathways, the oxidative stress pathway, the hypothalamic-pituitary-adrenal (HPA) axis, the metabolic and bioenergetics system, neurotrophic pathways, the glutamate system, the opioid system and the cholinergic system. For each of these systems, several targets have been assessed in preclinical and clinical models. Preclinical models strongly implicate these pathways in the patho-etiology of MDD. Clinical trials for TRD have been conducted for several novel targets; however, most of the trials discussed are small and several are uncontrolled. Therefore, further clinical trials are required to assess the true efficacy of these targets for TRD. As well, several promising novel agents have been clinically tested in MDD populations, but have yet to be assessed specifically for TRD. Thus, their applicability to TRD remains unknown.

Differentiating between the course of illness in bipolar 1 and chronic-psychotic heroin-dependent patients at their first agonist opioid treatment

In an effort to inquiry the "self-medication hypothesis" in heroin-dependent patients suffering from chronic psychosis and bipolar disorder, a naturalistic comparative cohort study was designed with the aim of comparing, according to the presence of dual diagnosis, the clinical characteristics of heroin-dependent patients presenting for their first agonist opioid treatment. The main finding was that addictive (heroin) illness was more severe in bipolar 1 patients and less severe in chronic psychotic patients when compared with heroin-dependent patients without dual diagnoses. In the case of chronic psychotic patients, these differences do not allow us to exclude a therapeutic heroin use, at least at the beginning of their toxicomanic career, with limited progression of their addictive disease. This occurrence seems to be excluded for bipolar 1 heroin-dependent patients, who come to their first agonist opioid treatment with a more severe addictive disease.

The relationship between vulnerable attachment style, psychopathology, drug abuse, and retention in treatment among methadone maintenance treatment patients

The relationship between vulnerable attachment style, psychopathology, drug abuse, and retention in treatment among patients in methadone maintenance treatment (MMT) was examined by the Vulnerable Attachment Style Questionnaire (VASQ), the Symptom Checklist-90 (SCL-90), and drug abuse urine tests. After six years, retention in treatment and repeated urine test results were studied. Patients with vulnerable attachment style (a high VASQ score) had higher rates of drug abuse and higher psychopathology levels compared to patients with secure attachment style, especially on the interpersonal sensitivity, anxiety, hostility, phobic anxiety, and paranoid ideation scales. Drug abstinence at baseline was related to retention in treatment and to higher rates of drug abstinence after six years in MMT, whereas a vulnerable attachment style could not predict drug abstinence and retention in treatment. Clinical Implications concerning treatment of drug abusing populations and methodological issues concerning the VASQ's subscales are also discussed.

Safety, tolerability, and clinical effect of low-dose buprenorphine for treatment-resistant depression in midlife and older adults

OBJECTIVE

To describe the clinical effect and safety of low-dose buprenorphine, a κ-opioid receptor antagonist, for treatment-resistant depression (TRD) in midlife and older adults.

METHOD

In an 8-week open-label study, buprenorphine was prescribed for 15 adults aged 50 years or older with TRD, diagnosed with the Structured Clinical Interview for DSM-IV, between June 2010 and June 2011. The titrated dose of buprenorphine ranged from 0.2-1.6 mg/d. We assessed clinical change in depression, anxiety, sleep, positive and negative affect, and quality of life. The Montgomery-Asberg Depression Rating scale (MADRS) served as the main outcome measure. Tolerability was assessed by documenting side effects and change in vital signs, weight, and cognitive function. Clinical response durability was assessed 8 weeks after discontinuation of buprenorphine.

RESULTS

The mean dose of buprenorphine was 0.4 mg/d (mean maximum dose = 0.7 mg/d). The mean depression score (MADRS) at baseline was 27.0 (SD = 7.3) and at week 8 was 9.5 (SD = 9.5). A sharp decline in depression severity occurred during the first 3 weeks of exposure (mean change = -15.0 [SD = 7.9]). Depression-specific items measuring pessimism and sadness indicated improvement during exposure, supporting a true antidepressant effect. Treatment-emergent side effects (in particular, nausea and constipation) were not sustained, vital signs and weight remained stable, and executive function and learning improved from pretreatment to posttreatment.

CONCLUSION

Low-dose buprenorphine may be a novel-mechanism medication that provides a rapid and sustained improvement for older adults with TRD. Placebo-controlled trials of longer duration are required to assess efficacy, safety, and physiologic and psychological effects of extended exposure to this medication.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01071538.

Evaluation of the agonist PET radioligand [¹¹C]GR103545 to image kappa opioid receptor in humans: kinetic model selection, test-retest reproducibility and receptor occupancy by the antagonist PF-04455242

INTRODUCTION

Kappa opioid receptors (KOR) are implicated in several brain disorders. In this report, a first-in-human positron emission tomography (PET) study was conducted with the potent and selective KOR agonist tracer, [(11)C]GR103545, to determine an appropriate kinetic model for analysis of PET imaging data and assess the test-retest reproducibility of model-derived binding parameters. The non-displaceable distribution volume (V(ND)) was estimated from a blocking study with naltrexone. In addition, KOR occupancy of PF-04455242, a selective KOR antagonist that is active in preclinical models of depression, was also investigated.

METHODS

For determination of a kinetic model and evaluation of test-retest reproducibility, 11 subjects were scanned twice with [(11)C]GR103545. Seven subjects were scanned before and 75 min after oral administration of naltrexone (150 mg). For the KOR occupancy study, six subjects were scanned at baseline and 1.5 h and 8 h after an oral dose of PF-04455242 (15 mg, n=1 and 30 mg, n=5). Metabolite-corrected arterial input functions were measured and all scans were 150 min in duration. Regional time-activity curves (TACs) were analyzed with 1- and 2-tissue compartment models (1TC and 2TC) and the multilinear analysis (MA1) method to derive regional volume of distribution (V(T)). Relative test-retest variability (TRV), absolute test-retest variability (aTRV) and intra-class coefficient (ICC) were calculated to assess test-retest reproducibility of regional VT. Occupancy plots were computed for blocking studies to estimate occupancy and V(ND). The half maximal inhibitory concentration (IC50) of PF-04455242 was determined from occupancies and drug concentrations in plasma. [(11)C]GR103545 in vivo K(D) was also estimated.

RESULTS

Regional TACs were well described by the 2TC model and MA1. However, 2TC VT was sometimes estimated with high standard error. Thus MA1 was the model of choice. Test-retest variability was ~15%, depending on the outcome measure. The blocking studies with naltrexone and PF-04455242 showed that V(T) was reduced in all regions; thus no suitable reference region is available for the radiotracer. V(ND) was estimated reliably from the occupancy plot of naltrexone blocking (V(ND)=3.4±0.9 mL/cm(3)). The IC50 of PF-04455242 was calculated as 55 ng/mL. [(11)C]GR103545 in vivo K(D) value was estimated as 0.069 nmol/L.

CONCLUSIONS

[(11)C]GR103545 PET can be used to image and quantify KOR in humans, although it has slow kinetics and variability of model-derived kinetic parameters is higher than desirable. This tracer should be suitable for use in receptor occupancy studies, particularly those that target high occupancy.

The long winding road of opioid substitution therapy implementation in South-East Asia: challenges to scale up

The South-East Asia Region contains an estimated 400,000-500,000 people who inject drugs (PWID). HIV prevalence among PWID is commonly 20% or higher in Indonesia, Thailand, Myanmar and some regions of India. Opioid substitution therapy (OST) is an important HIV prevention intervention in this part of the world. However, key challenges and barriers to scale up of OST exist, including: pervasive stigma and discrimination towards PWID; criminalisation of drug use overshadowing a public health response; lack of political will and national commitment; low financial investment; focus towards traditional treatment models of detoxification and rehabilitation; inadequate dosing of OST; and poor monitoring and evaluation of programmes. Our review of local evidence highlights that OST can be successful within the Asian context. Such evidence should be utilised more widely to advocate for policy change and increased political commitment to ensure OST reaches substantially more drug users. Significance for public healthSeveral countries in the World Health Organization South-East Asia Region can be commended for introducing opioid substitution therapy (OST) to address the ongoing HIV epidemic among people who inject drugs (PWID). Local evidence shows OST is an effective drug treatment approach in the Asian context given sufficient technical and institutional support. However, despite much progress, the number of OST dispensing sites and recipients remains totally inadequate in terms of impact upon the current HIV epidemic among PWID. Ongoing advocacy is needed if countries are to achieve the WHO's target of 40% of PWID being dosed with OST. Greater political commitment a strengthened policy environment, capacity building for OST clinics, lessening the criminalisation of drug use and promoting a public health response will give many more PWID access to OST and slow the advance of the HIV epidemic.

Effects of pain and prescription opioid use on outcomes in a collaborative care intervention for anxiety

OBJECTIVE

To determine the effects of pain and opioid pain medication use on clinical and functional outcomes in 1004 primary care patients with an anxiety disorder randomized to receive the Coordinated Anxiety Learning and Management (CALM) collaborative care intervention (cognitive-behavioral therapy and/or medication) versus usual care.

METHODS

A total of 1004 patients with panic disorder, generalized anxiety disorder, social anxiety disorder, or posttraumatic stress disorder were randomized to CALM or usual care. Outcomes at 6, 12, and 18 months were compared in patients with and without moderate pain interference (for the entire anxiety disorder group and then just those with comorbid major depression) and in patients taking and not taking opioid medication (entire group, just those with comorbid major depression, and just those with moderate pain interference).

RESULTS

Patients with pain interference and patients taking opioid pain medication were more anxious [Brief Symptom Inventory anxiety subscale] and disabled (Sheehan Disability) at baseline, improved over time at similar rates, but at 18 months had lower response and remission rates. There was no moderating effect on the intervention. In patients with comorbid major depression, patients using opioid medications showed a trend for less disability improvement over time, and in patients with pain, patients using opioids showed less sustained anxiety response at 18 months.

CONCLUSIONS

Anxious patients with pain benefit as much as those without pain from cognitive-behavioral therapy and medication treatment. Among patients with pain, however, there is some evidence of a reduced anxiety treatment response in those taking opioid medication, which should be further studied.

The missing 'P' in pain management: how the current opioid epidemic highlights the need for psychiatric services in chronic pain care

OBJECTIVE

The prevalence of opioid therapy for chronic noncancer pain has increased dramatically in recent years, with a parallel increase in opioid abuse, misuse and deaths from accidental overdose. We review epidemiological and clinical data that point to the important roles psychiatric disorders have in the use and abuse of opioids in patients with chronic pain.

METHOD

We conducted literature searches on the PubMed with the key phrases "chronic pain" and "opioid therapy" and selected those articles on the epidemiology of comorbidity between chronic pain and psychiatric disorders, the trends in long-term opioid therapy and the clinical trials that involved using opioid therapy for chronic pain or for mental health disorders. We then thoroughly reviewed the bibliography of all relevant articles to identify additional papers to be included in the present review.

RESULTS

Chronic pain is highly comorbid with common psychiatric disorders. Patients with mental health and substance abuse disorders are more likely to receive long-term opioid therapy for chronic pain and more likely to have adverse outcomes from this therapy. Although opioids may exert brief antidepressant and anxiolytic effects in some patients with depression or anxiety, there is scant evidence for long-term benefit from opioid treatment of psychiatric disorders.

CONCLUSIONS

Opioids may be used in current clinical practice as the de facto and only psychiatric treatment for patients with chronic pain, despite little evidence for sustained benefit. The opioid epidemic thus reflects a serious unmet need for better recognition and treatment of common mental health problems in patients with chronic pain. Psychiatry is the missing P in chronic pain care.

Depression and ambivalence toward chronic opioid therapy for chronic noncancer pain

OBJECTIVES

Chronic opioid therapy (COT) for chronic noncancer pain (CNCP) is characterized by both high rates of patient-initiated discontinuation and by perceived helpfulness among those who sustain opioid use. This study examines predictors of the desire to cut down or stop opioid therapy among patients receiving COT who report that opioids are helpful for relieving pain.

METHODS

We conducted a cross-sectional survey of 1737 selected patients receiving COT for CNCP who perceived opioids to be helpful in relieving their pain. Ambivalence about opioid use was assessed by agreement/disagreement with a statement indicating that they would like to stop or cut down the use of prescribed opioid medications. Depression was measured with the 8-item Patient Health Questionnaire.

RESULTS

A high percentage (43.3%) of survey respondents who found opioids helpful also reported the desire to stop or cut down opioids. Half of these patients reporting the desire to stop or cut down were clinically depressed, compared with a third of those not wanting to stop or cut down, a highly significant difference after controlling for covariates (P<0.0001). The group wanting to stop or cut down opioid use also reported significantly higher levels of opioid-related psychosocial problems and opioid control concerns.

DISCUSSION

There are high rates of ambivalence about opioid use among COT recipients who consider opioids helpful for pain relief. Depressed patients are more likely to be ambivalent about use of prescribed opioids. Eliciting patient ambivalence may be helpful in patients who are not benefiting from long-term opioid use as an initial step toward consideration of discontinuation.

Opioid receptors: distinct roles in mood disorders

The roles of opioid receptors in pain and addiction have been extensively studied, but their function in mood disorders has received less attention. Accumulating evidence from animal research reveals that mu, delta and kappa opioid receptors (MORs, DORs and KORs, respectively) exert highly distinct controls over mood-related processes. DOR agonists and KOR antagonists have promising antidepressant potential, whereas the risk-benefit ratio of currently available MOR agonists as antidepressants remains difficult to evaluate, in addition to their inherent abuse liability. To date, both human and animal studies have mainly examined MORs in the etiology of depressive disorders, and future studies will address DOR and KOR function in established and emerging neurobiological aspects of depression, including neurogenesis, neurodevelopment, and social behaviors.

Depression and prescription opioid misuse among chronic opioid therapy recipients with no history of substance abuse

PURPOSE

Opioid misuse in the context of chronic opioid therapy (COT) is a growing concern. Depression may be a risk factor for opioid misuse, but it has been difficult to tease out the contribution of co-occurring substance abuse. This study aims to examine whether there is an association between depression and opioid misuse in patients receiving COT who have no history of substance abuse.

METHODS

A telephone survey was conducted at Group Health Cooperative and Kaiser Permanente of Northern California. We interviewed 1,334 patients on COT for noncancer pain who had no history of substance abuse. Patients were asked about 3 forms of opioid misuse: (1) self-medicating for symptoms other than pain, (2) self-increasing doses, and (3) giving to or getting opioids from others. Depression was evaluated by the 8-item Patient Health Questionnaire (PHQ-8).

RESULTS

Compared with patients who were not depressed (PHQ-8 score 0 to 4), patients with moderate depression (PHQ-8 score 10 to 14) and severe depression (PHQ-8 score 15 or higher) were 1.8 and 2.4 times more likely, respectively, to misuse their opioid medications for non-pain symptoms. Patients with mild (PHQ-8 score 5 to 9), moderate, and severe depression were 1.9, 2.9, and 3.1 times more likely, respectively, to misuse their opioid medications by self-increasing their dose. There was no statistically significant association between depression and giving opioids to or getting them from others.

CONCLUSION

In patients with no substance abuse history, depressive symptoms are associated with increased rates of some forms of self-reported opioid misuse. Clinicians should be alert to the risk of patients with depressive symptoms using opioids to relieve these symptoms and thereby using more opioids than prescribed.

BAP updated guidelines: evidence-based guidelines for the pharmacological management of substance abuse, harmful use, addiction and comorbidity: recommendations from BAP

The British Association for Psychopharmacology guidelines for the treatment of substance abuse, harmful use, addiction and comorbidity with psychiatric disorders primarily focus on their pharmacological management. They are based explicitly on the available evidence and presented as recommendations to aid clinical decision making for practitioners alongside a detailed review of the evidence. A consensus meeting, involving experts in the treatment of these disorders, reviewed key areas and considered the strength of the evidence and clinical implications. The guidelines were drawn up after feedback from participants. The guidelines primarily cover the pharmacological management of withdrawal, short- and long-term substitution, maintenance of abstinence and prevention of complications, where appropriate, for substance abuse or harmful use or addiction as well management in pregnancy, comorbidity with psychiatric disorders and in younger and older people.

Increased anxiety-like behaviors in rats experiencing chronic inflammatory pain

For many patients, chronic pain is often accompanied, and sometimes amplified, by co-morbidities such as anxiety and depression. Although it represents important challenges, the establishment of appropriate preclinical behavioral models contributes to drug development for treating chronic inflammatory pain and associated psychopathologies. In this study, we investigated whether rats experiencing persistent inflammatory pain induced by intraplantar injection of complete Freund's adjuvant (CFA) developed anxiety-like behaviors, and whether clinically used analgesic and anxiolytic drugs were able to reverse CFA-induced anxiety-related phenotypes. These behaviors were evaluated over 28 days in both CFA- and saline-treated groups with a variety of behavioral tests. CFA-induced mechanical allodynia resulted in increased anxiety-like behaviors as evidenced by: (1) a significant decrease in percentage of time spent and number of entries in open arms of the elevated-plus maze (EPM), (2) a decrease in number of central squares visited in the open field (OF), and (3) a reduction in active social interactions in the social interaction test (SI). The number of entries in closed arms in the EPM and the distance traveled in the OF used as indicators of locomotor performance did not differ between treatments. Our results also reveal that in CFA-treated rats, acute administration of morphine (3mg/kg, s.c.) abolished tactile allodynia and anxiety-like behaviors, whereas acute administration of diazepam (1mg/kg, s.c) solely reversed anxiety-like behaviors. Therefore, pharmacological treatment of anxiety-like behaviors induced by chronic inflammatory pain can be objectively evaluated using multiple behavioral tests. Such a model could help identify/validate alternative potential targets that influence pain and cognitive dimensions of anxiety.

Dyspnea review for the palliative care professional: treatment goals and therapeutic options

Although dyspnea is frequently encountered in the palliative care setting, its optimal management remains uncertain. Clinical approaches begin with accurate assessment, as delineated in part one of this two-part series. Comprehensive dyspnea assessment, which encompasses the physical, emotional, social, and spiritual aspects of this complex symptom, guide the clinician in choosing therapeutic approaches herein presented as part two. Global management of dyspnea is appropriate both as complementary to disease-targeted treatments that target the underlying etiology, and as the sole focus when the symptom has become intractable, disease is maximally treated, and goals of care shift to comfort and quality of life. In this setting, current evidence supports the use of oral or parenteral opioids as the mainstay of dyspnea management, and of inhaled furosemide and anxiolytics as adjuncts. Nonpharmacologic interventions such as acupuncture and pulmonary rehabilitation have potential effectiveness, although further research is needed, and use of a simple fan warrants consideration given its potential benefit and minimal burden and cost.

Psychiatric comorbidity in a sample of opiate-dependent patients treated with sublingual buprenorphine in a therapeutic community regime

INTRODUCTION

The purpose of this work is to estimate the prevalence of psychiatric cases in a sample of opiate-dependent patients treated with sublingual buprenorphine in a therapeutic community regime, and to describe their progress during the first month of treatment.

METHODS

An observational, longitudinal, prospective study was conducted. Of the 119 opiate-dependent patients selected, 46 agreed to start treatment with buprenorphine. For organisational reasons, the psychopathological assessment was carried out on 36 of these patients. The measurement tools used were the MINI, GHQ-28, IPDE and Assessment of the Quality of Life in Psychoactive Substance Addicts (TEQLASP).

RESULTS

The prevalence rate of any psychiatric disorder was 78%. The prevalence of Axis I diagnoses was 69.4%. The prevalence of cases in Axis II was 58.3%, and 50% of patients had concomitant Axis I and Axis II disorders. The patients with Axis I psychiatric disorders showed a significant reduction in the mean scores of the GHQ-28 scale, and in the B (anxiety/unease), C (social dysfunction), and D (depression) subscales of the GHQ-28. The differences observed between the patients with no psychiatric disorders after one month of treatment were not significant. An improvement in the quality of life wad observed in both groups, although these changes were of a lower magnitude in the group with psychiatric disorders.

DISCUSSION

The results of this study show a very high frequency of psychiatric disorders. For this reason, psychiatric illness must be actively looked for whenever we assess a drug-dependent patient.

Depression: a repair response to stress-induced neuronal microdamage that can grade into a chronic neuroinflammatory condition?

Depression is a major contributor to the global burden of disease and disability, yet it is poorly understood. Here we review data supporting a novel theoretical model for the biology of depression. In this model, a stressful life event leads to microdamage in the brain. This damage triggers an injury repair response consisting of a neuroinflammatory phase to clear cellular debris and a spontaneous tissue regeneration phase involving neurotrophins and neurogenesis. During healing, released inflammatory mediators trigger sickness behavior and psychological pain via mechanisms similar to those that produce physical pain during wound healing. The depression remits if the neuronal injury repair process resolves successfully. Importantly, however, the acute psychological pain and neuroinflammation often transition to chronicity and develop into pathological depressive states. This hypothesis for depression explains substantially more data than alternative models, including why emerging data show that analgesic, anti-inflammatory, pro-neurogenic and pro-neurotrophic treatments have antidepressant effects. Thus, an acute depressive episode can be conceptualized as a normally self-limiting but highly error-prone process of recuperation from stress-triggered neuronal microdamage.

Augmentation strategies in electroconvulsive therapy

Electroconvulsive therapy (ECT) is a highly effective treatment, but strategies to enhance therapeutic outcomes are occasionally needed. This review examines the evidence for approaches used for enhancing seizure production: hyperventilation, pretreatment with xanthines, and use of remifentanil or ketamine in ECT anesthesia. Hyperventilation may be a useful strategy to enhance seizure production, but its effects on ECT outcomes have not been systematically studied and require further research. Pretreatment with caffeine, theophylline or aminophylline (xanthines) prolongs the duration of ECT seizures but has not been clearly shown in controlled trials to increase efficacy. Caution is also warranted because their use may be associated with significant adverse effects. There are case reports of the usefulness of remifentanil in assisting seizure induction by reducing the dose of barbiturate anesthetic required, but there are no controlled data on whether it independently enhances efficacy outcomes. Preliminary evidence suggests that ketamine and ECT may have synergistic antidepressant effects, although this needs to be further examined in randomized controlled trials.

Antidepressant treatment does not improve buprenorphine retention among opioid-dependent persons

Our goal was to determine whether treatment of depressive symptoms with escitalopram during buprenorphine treatment for opioid dependence would improve treatment retention compared to placebo in a 12-week, randomized, double-blind trial. Treatment dropout was defined as missing seven consecutive buprenorphine dosing days. Participants were 76% male, 80% non-Hispanic Caucasian, and 64% heroin users. At baseline, the mean Beck Depression Inventory II (BDI-II) score was 28.4 (+/-9.7). Sixty-one percent of participants completed the 12-week buprenorphine protocol. Dropout rates were 33.3% and 44.0% among those randomized to escitalopram or placebo, respectively (p = .19). Relative to baseline, mean BDI-II scores were significantly lower at all follow-up assessments, but the Treatment x Time interaction effect was not statistically significant (p = .18). Participants randomized to escitalopram also did not have a significantly lower likelihood of testing positive for either opiates or other drugs during follow-up. Depressive symptoms often resolved with buprenorphine treatment, and the immediate initiation of escitalopram does not improve treatment retention, depression outcomes, or illicit drug use. Clinicians should determine the need for antidepressant treatment later in buprenorphine care.