Intranasal as needed naloxone in the treatment of gambling disorder: A randomised controlled trial

Pharmacological management of gambling disorder: A systematic review and network meta-analysis

BACKGROUND

Clinical guidelines remain unclear on which medications for gambling disorder are to be preferred in terms of efficacy and tolerability. We aimed to compare pharmacological treatments for gambling disorder in terms of efficacy and tolerability, using network meta-analysis (NMA).

METHODS

Based on our pre-registered protocol [CRD42022329520], a structured search was conducted across broad range of databases, for double-blind randomized controlled trials (RCTs) of medications for gambling disorder. Data were independently extracted by two researchers. We used standardized mean differences (SMD) using Hedges' g to measure the efficacy outcomes, and for the effect for tolerability we used dropout rate due to medication side effects, expressed as odds ratio (OR). Confidence in the network estimates was assessed using the CINeMA framework. We followed the PRISMA-NMA guidelines for this work. Outcomes were gambling symptom severity and quality of life (for efficacy), and tolerability.

FINDINGS

We included 22 RCTs in the systematic review and 16 RCTs (n = 977 participants) in the NMA. Compared with placebo, moderate confidence evidence indicated that nalmefene [Standardized Mean Difference (SMD): -0.86; 95 % confidence interval (CI: -1.32,-0.41)] reduced gambling severity, followed by naltrexone (SMD: -0.42; 95 %CI: (-0.85,0.01)). Naltrexone (SMD: -0.50; 95 %CI: (-0.85,-0.14)) and nalmefene (SMD: -0.36; 95 %CI: (-0.72,-0.01) were also more beneficial than placebo in terms of quality of life. Olanzapine and topiramate were not more efficacious than placebo. Nalmefene [Odds Ratio (OR): 7.55; 95 %CI: (2.24-25.41)] and naltrexone (OR: 7.82; 95 %CI: (1.26-48.70)) had significantly higher dropout due to side effects (lower tolerability) compared with placebo.

INTERPRETATION

Based on NMA, nalmefene and naltrexone currently have the most supportive evidence for the pharmacological treatment of gambling disorder. Further clinical trials of novel compounds, and analysis of individual participant data are needed, to strengthen the evidence base, and help tailor treatments at the individual patient level.

Screening and Treatment for Co-occurring Gambling and Substance Use: A Scoping Review

There is a high prevalence of gambling harms co-occurring with substance use harms. Where harms are co-occurring, they may be experienced as more severe. However, there is little evidence that services are systematically screening for such co-occurring harms in treatment-seeking populations. Furthermore, treatment modalities remain relatively under-developed, with treatment usually addressing only one source of harm.This scoping review looks at the current literature on screening and therapeutic interventions for co-occurring gambling and substance use harms to understand how co-occurring harms may be managed in a treatment setting. It draws together available data on the intersections of substance use harms and gambling related harms, in a treatment context.This research identifies a range of potentially useful validated tools for clinicians in substance use treatment settings to screen for gambling harms. For workers in gambling treatment settings who are seeking validated tools to screen for co-occurring substance use harms, the literature provides less guidance.The validated toolbox of therapeutic interventions for those experiencing co-occurring substance use and gambling harms is relatively sparse. Psychosocial interventions appear to offer the best outcomes on gambling measures for those experiencing co-occurring substance use harms. Further research is needed to establish the benefits of different combinations of treatment and treatment types in achieving reductions across both substance use and gambling harms, when these harms are experienced concurrently.

Validation of a Spanish Adaptation of the Gambling Symptom Assessment Scale (G-SAS) in Persons with Recent History of Gambling

Gambling is becoming increasingly frequent and problematic, especially due to the explosion of online alternatives. Evaluating the severity of gambling symptomatology is therefore more important than ever. However, innovations in the gambling field have generally focused on its treatment rather than its evaluation. The Gambling Symptom Assessment Scale (G-SAS) is a well-established measure of gambling-related symptomatology (e.g., gambling urges, gambling-related thoughts and behaviours, and interpersonal functioning). The aim of this study is to validate a Spanish adaptation of the G-SAS so that individual differences in gambling symptomatology can be assessed by clinicians and researchers. The internal structure of the G-SAS was investigated using an exploratory factor analysis with a sample of 364 individuals from the general population in Spain (mean age = 28.84 years, SD = 11.73; 54% males). A four-factor structure was preferred considering fit indices (Chi-square = 22.62, p = .162, RMSEA = 0.030, CFI = 0.998, TLI = 0.995) and internal consistency estimates (0.67 ≤ α ≤ 0.89). The factors were labelled gambling-related symptoms, control of gambling urges/thoughts, interference, and arousal. Regarding construct validity, the four factors of the G-SAS were positively and significantly (all p < .001) correlated with measures of problematic gambling severity (0.40 ≤ r ≤ .73), problematic gambling diagnostic (0.40 ≤ r ≤ .67), gambling cognitions (0.48 ≤ r ≤ .57), impulsivity (0.26 ≤ r ≤ .42), anxiety (0.22 ≤ r ≤ .38), and depression (0.16 ≤ r ≤ .42), and negatively with quality of life (-0.24 ≤ r≤-.42). In sum, this study provides Spanish clinicians and researchers with a tool that serves to assess the status of individuals in relation to gambling symptomatology, which can be used to screen for at-risk profiles and evaluate treatment response.

Endogenous opiates and behavior: 2022

This paper is the forty-fifth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2022 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Pharmacological interventions for the treatment of disordered and problem gambling

BACKGROUND

Pharmacological interventions for disordered and problem gambling have been employed in clinical practice. Despite the availability of several reviews of the efficacy of pharmacological interventions for disordered or problem gambling, few have employed systematic search strategies or compared different categories of pharmacological interventions. Systematic reviews of high-quality evidence are therefore essential to provide guidance regarding the efficacy of different pharmacological interventions for disordered or problem gambling.

OBJECTIVES

The primary aims of the review were to: (1) examine the efficacy of major categories of pharmacological-only interventions (antidepressants, opioid antagonists, mood stabilisers, atypical antipsychotics) for disordered or problem gambling, relative to placebo control conditions; and (2) examine the efficacy of these major categories relative to each other.  SEARCH METHODS: We searched the Cochrane Common Mental Disorders Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Embase, and PsycINFO (all years to 11 January 2022).

SELECTION CRITERIA

We included randomised trials evaluating a pharmacological intervention for the treatment of disordered or problem gambling. Eligible control conditions included placebo control groups or comparisons with another category of pharmacological intervention.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures, including systematic extraction of included study characteristics and results and risk of bias assessment. Our primary outcome was reduction in gambling symptom severity. Our secondary outcomes were reduction in gambling expenditure, gambling frequency, time spent gambling, depressive symptoms, anxiety symptoms, and functional impairment; and responder status. We evaluated treatment effects for continuous and dichotomous outcomes using standardised mean difference (SMD) and risk ratios (RR), respectively, employing random-effects meta-analyses. A minimum of two independent treatment effects were required for a meta-analysis to be conducted (with only meta-analytic findings reported in this abstract).

MAIN RESULTS

We included 17 studies in the review (n = 1193 randomised) that reported outcome data scheduled for end of treatment. Length of treatment ranged from 7 to 96 weeks.  Antidepressants: Six studies (n = 268) evaluated antidepressants, with very low to low certainty evidence suggesting that antidepressants were no more effective than placebo at post-treatment: gambling symptom severity (SMD -0.32, 95% CI -0.74 to 0.09, n = 225), gambling expenditure (SMD -0.27, 95% CI -0.60 to 0.06, n = 144), depressive symptoms (SMD -0.19, 95% CI -0.60 to 0.23, n = 90), functional impairment (SMD -0.15, 95% CI -0.53 to 0.22, n = 110), and responder status (RR 1.24, 95% CI 0.93 to 1.66, n = 268). Opioid antagonists: Four studies (n = 562) evaluated opioid antagonists, with very low to low certainty evidence showing a medium beneficial effect of treatment on gambling symptom severity relative to placebo at post-treatment (SMD -0.46, 95% CI -0.74 to -0.19, n = 259), but no difference between groups in responder status (RR 1.65, 95% CI 0.86 to 3.14, n = 562). Mood stabilisers: Two studies (n = 71) evaluated mood stabilisers (including anticonvulsants), with very low certainty evidence suggesting that mood stabilisers were no more effective than placebo at post-treatment: gambling symptom severity (SMD -0.92, 95% CI -2.24 to 0.39, n = 71), depressive symptoms (SMD -0.15, 95% CI -1.14 to 0.83, n = 71), and anxiety symptoms (SMD -0.17, 95% CI -0.64 to 0.30, n = 71). Atypical antipsychotics:Two studies (n = 63) evaluated the atypical antipsychotic olanzapine, with very low certainty evidence showing a medium beneficial effect of treatment on gambling symptom severity relative to placebo at post-treatment (SMD -0.59, 95% CI -1.10 to -0.08, n = 63). Comparative effectiveness: Two studies (n = 62) compared antidepressants with opioid antagonists, with very low certainty evidence indicating that antidepressants were no more effective than opioid antagonists on depressive symptoms (SMD 0.22, 95% CI -0.29 to 0.72, n = 62) or anxiety symptoms (SMD 0.21, 95% CI -0.29 to 0.72, n = 62) at post-treatment. Two studies (n = 58) compared antidepressants with mood stabilisers (including anticonvulsants), with very low certainty evidence indicating that antidepressants were no more effective than mood stabilisers on depressive symptoms (SMD 0.02, 95% CI -0.53 to 0.56, n = 58) or anxiety symptoms (SMD 0.16, 95% CI -0.39 to 0.70, n = 58) at post-treatment. Tolerability and adverse events: Several common adverse effects were reported by participants receiving antidepressants (e.g. headaches, nausea, diarrhoea/gastrointestinal issues) and opioid antagonists (e.g. nausea, dry mouth, constipation). There was little consistency in the types of adverse effects experienced by participants receiving mood stabilisers (e.g. tiredness, headaches, concentration difficulties) or atypical antipsychotics (e.g. pneumonia, sedation, increased hypomania). Discontinuation of treatment due to these adverse events was highest for opioid antagonists (10% to 32%), followed by antidepressants (4% to 31%), atypical antipsychotics (14%), and mood stabilisers (13%).

AUTHORS' CONCLUSIONS

This review provides preliminary support for the use of opioid antagonists (naltrexone, nalmefene) and atypical antipsychotics (olanzapine) to produce short-term improvements in gambling symptom severity, although a lack of available evidence precludes a conclusion regarding the degree to which these pharmacological agents can improve other gambling or psychological functioning indices. In contrast, the findings are inconclusive with regard to the effects of mood stabilisers (including anticonvulsants) in the treatment of disordered or problem gambling, and there is limited evidence to support the efficacy of antidepressants. However, these conclusions are based on very low to low certainty evidence characterised by a small number of included studies, high risk of bias, modest pooled sample sizes, imprecise estimates, moderate between-study heterogeneity, and exclusion of participants with psychiatric comorbidities. Moreover, there were insufficient studies to conduct meta-analyses on many outcome measures; to compare efficacy across and within major categories of interventions; to explore dosage effects; or to examine effects beyond post-treatment. These limitations suggest that, despite recommendations related to the administration of opioid antagonists in the treatment of disordered or problem gambling, pharmacological interventions should be administered with caution and with careful consideration of patient needs. A larger and more methodologically rigorous evidence base with longer-term evaluation periods is required before definitive conclusions can be drawn about the effectiveness and durability of pharmacological treatments for disordered or problem gambling.