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Dive into the research topics where Vikki Charles is active.

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Featured researches published by Vikki Charles.


The Lancet | 2010

Supervised injectable heroin or injectable methadone versus optimised oral methadone as treatment for chronic heroin addicts in England after persistent failure in orthodox treatment (RIOTT): a randomised trial

John Strang; Nicola Metrebian; Nicholas Lintzeris; Laura Potts; Tom Carnwath; Soraya Mayet; Hugh Williams; Deborah Zador; Richard Evers; Teodora Groshkova; Vikki Charles; Anthea Martin; Luciana Forzisi

BACKGROUND Some heroin addicts persistently fail to benefit from conventional treatments. We aimed to compare the effectiveness of supervised injectable treatment with medicinal heroin (diamorphine or diacetylmorphine) or supervised injectable methadone versus optimised oral methadone for chronic heroin addiction. METHODS In this multisite, open-label, randomised controlled trial, we enrolled chronic heroin addicts who were receiving conventional oral treatment (>or=6 months), but continued to inject street heroin regularly (>or=50% of days in preceding 3 months). Randomisation by minimisation was used to assign patients to receive supervised injectable methadone, supervised injectable heroin, or optimised oral methadone. Treatment was provided for 26 weeks in three supervised injecting clinics in England. Primary outcome was 50% or more of negative specimens for street heroin on weekly urinalysis during weeks 14-26. Primary analysis was by intention to treat; data were adjusted for centre, regular crack use at baseline, and treatment with optimised oral methadone at baseline. Percentages were calculated with Rubins rules and were then used to estimate numbers of patients in the multiple imputed samples. This study is registered, ISRCTN01338071. FINDINGS Of 301 patients screened, 127 were enrolled and randomly allocated to receive injectable methadone (n=42 patients), injectable heroin (n=43), or oral methadone (n=42); all patients were included in the primary analysis. At 26 weeks, 80% (n=101) patients remained in assigned treatment: 81% (n=34) on injectable methadone, 88% (n=38) on injectable heroin, and 69% (n=29) on oral methadone. Patients on injectable heroin were significantly more likely to have achieved the primary outcome (72% [n=31]) than were those on oral methadone (27% [n=11], OR 7.42, 95% CI 2.69-20.46, p<0.0001; adjusted: 66% [n=28] vs 19% [n=8], 8.17, 2.88-23.16, p<0.0001), with number needed to treat of 2.17 (95% CI 1.60-3.97). For injectable methadone (39% [n=16]; adjusted: 30% [n=14]) versus oral methadone, the difference was not significant (OR 1.74, 95% CI 0.66-4.60, p=0.264; adjusted: 1.79, 0.67-4.82, p=0.249). For injectable heroin versus injectable methadone, a significant difference was recorded (4.26, 1.63-11.14, p=0.003; adjusted: 4.57, 1.71-12.19, p=0.002), but the study was not powered for this comparison. Differences were evident within the first 6 weeks of treatment. INTERPRETATION Treatment with supervised injectable heroin leads to significantly lower use of street heroin than does supervised injectable methadone or optimised oral methadone. UK Government proposals should be rolled out to support the positive response that can be achieved with heroin maintenance treatment for previously unresponsive chronic heroin addicts. FUNDING Community Fund (Big Lottery) Research section, through Action on Addiction.


The Lancet | 2014

Use of contingency management incentives to improve completion of hepatitis B vaccination in people undergoing treatment for heroin dependence: a cluster randomised trial

Tim Weaver; Nicola Metrebian; Jennifer Hellier; Stephen Pilling; Vikki Charles; Nicholas Little; Dilkushi Poovendran; Luke Mitcheson; Frank Ryan; Owen Bowden-Jones; John Shaw Dunn; Anthony Glasper; Emily Finch; John Strang

BACKGROUND Poor adherence to treatment diminishes its individual and public health benefit. Financial incentives, provided on the condition of treatment attendance, could address this problem. Injecting drug users are a high-risk group for hepatitis B virus (HBV) infection and transmission, but adherence to vaccination programmes is poor. We aimed to assess whether contingency management delivered in routine clinical practice increased the completion of HBV vaccination in individuals receiving opioid substitution therapy. METHODS In our cluster randomised controlled trial, we enrolled participants at 12 National Health Service drug treatment services in the UK that provided opioid substitution therapy and nurse-led HBV vaccination with a super-accelerated schedule (vaccination days 0, 7, and 21). Clusters were randomly allocated 1:1:1 to provide vaccination without incentive (treatment as usual), with fixed value contingency management (three £10 vouchers), or escalating value contingency management (£5, £10, and £15 vouchers). Both contingency management schedules rewarded on-time attendance at appointments. The primary outcome was completion of clinically appropriate HBV vaccination within 28 days. We also did sensitivity analyses that examined vaccination completion with full adherence to appointment times and within a 3 month window. The trial is registered with Current Controlled Trials, number ISRCTN72794493. FINDINGS Between March 16, 2011, and April 26, 2012, we enrolled 210 eligible participants. Compared with six (9%) of 67 participants treated as usual, 35 (45%) of 78 participants in the fixed value contingency management group met the primary outcome measure (odds ratio 12·1, 95% CI 3·7-39·9; p<0·0001), as did 32 (49%) of 65 participants in the escalating value contingency management group (14·0, 4·2-46·2; p<0·0001). These differences remained significant with sensitivity analyses. INTERPRETATION Modest financial incentives delivered in routine clinical practice significantly improve adherence to, and completion of, HBV vaccination programmes in patients receiving opioid substitution therapy. Achievement of this improvement in routine clinical practice should now prompt actual implementation. Drug treatment providers should employ contingency management to promote adherence to vaccination programmes. The effectiveness of routine use of contingency management to achieve long-term behaviour change remains unknown. FUNDING National Institute for Health Research (RP-PG-0707-10149).


British Journal of Psychiatry | 2013

Cost-effectiveness of injectable opioid treatment v. oral methadone for chronic heroin addiction

Sarah Byford; Barbara Barrett; Nicola Metrebian; Teodora Groshkova; Maria Cary; Vikki Charles; Nicholas Lintzeris; John Strang

BACKGROUND Despite evidence of the effectiveness of injectable opioid treatment compared with oral methadone for chronic heroin addiction, the additional cost of injectable treatment is considerable, and cost-effectiveness uncertain. AIMS To compare the cost-effectiveness of supervised injectable heroin and injectable methadone with optimised oral methadone for chronic refractory heroin addiction. METHOD Multisite, open-label, randomised controlled trial. Outcomes were assessed in terms of quality-adjusted life-years (QALYs). Economic perspective included health, social services and criminal justice resources. RESULTS Intervention costs over 26 weeks were significantly higher for injectable heroin (mean £8995 v. £4674 injectable methadone and £2596 oral methadone; P<0.0001). Costs overall were highest for oral methadone (mean £15 805 v. £13 410 injectable methadone and £10 945 injectable heroin; P = n.s.) due to higher costs of criminal activity. In cost-effectiveness analysis, oral methadone was dominated by injectable heroin and injectable methadone (more expensive and less effective). At willingness to pay of £30 000 per QALY, there is a higher probability of injectable methadone being more cost-effective (80%) than injectable heroin. CONCLUSIONS Injectable opioid treatments are more cost-effective than optimised oral methadone for chronic refractory heroin addiction. The choice between supervised injectable heroin and injectable methadone is less clear. There is currently evidence to suggest superior effectiveness of injectable heroin but at a cost that policy makers may find unacceptable. Future research should consider the use of decision analytic techniques to model expected costs and benefits of the treatments over the longer term.


Journal of Mental Health | 2010

A qualitative study of illicit and non-prescribed drug use amongst people with psychotic disorders

Vikki Charles; Tim Weaver

Background: The reasons for drug use amongst people with psychosis are poorly understood. Aims: To investigate patterns of drug use and self-reported reasons for drug use amongst people with psychosis. Method: Qualitative interviews with 14 patients with psychosis who misuse drugs. Results: Most participants felt drug use was implicated in the development or exacerbation of psychosis. Most changed their pattern of drug use post-onset, reported transient motivation to abstain from drug use but became discerning drug users. Despite awareness of the negative physical and mental health consequences of drug use participants reported that drugs were used for social reasons, to achieve pleasurable intoxication, to relieve dysphoria or the side effects of anti-psychotic medication and to enhance or modify mood. Self-medication in response to psychotic symptoms was not reported. Conclusions: Participants described reasons for drug use that were consistent with those previously reported, but we found no strong evidence that patients self-medicated in response to their psychotic symptoms. Transient motivation to abstain from drug use may provide opportunities for intervention but psychiatric professionals need to assess each patients motivations for use to intervene effectively.


Addiction | 2015

Drug use, health and social outcomes of hard-to-treat heroin addicts receiving supervised injectable opiate treatment: secondary outcomes from the Randomized Injectable Opioid Treatment Trial (RIOTT)

Nicola Metrebian; Teodora Groshkova; Jennifer Hellier; Vikki Charles; Anthea Martin; Luciana Forzisi; Nicholas Lintzeris; Deborah Zador; Hugh Williams; Tom Carnwath; Soraya Mayet; John Strang

AIMS The Randomized Injectable Opioid Treatment Trial (RIOTT) compared supervised injectable heroin (SIH) and supervised injectable methadone (SIM) with optimized oral methadone (OOM) (ISRCTN0133807). Heroin addicts (previously unresponsive to treatment) made significant reductions in street heroin use at 6 months when treated with SIH. We now examine secondary outcomes. DESIGN Multi-site randomized controlled trial (RCT) comparing SIH versus OOM and SIM versus OOM. SETTING Three supervised injectable opiate clinics in England. PARTICIPANTS Chronic refractory heroin addicts continuing to inject street heroin virtually daily despite oral substitution treatment (n = 127), randomized to either SIH(n = 43), SIM(n = 42) or OOM(n = 42). All received high levels of medical and psychosocial support. MEASUREMENTS SECONDARY OUTCOMES wider drug use, crime, health and social functioning at 6 months. FINDINGS At 6 months, no significant differences were found between treatment groups in wider drug use (crack/cocaine, benzodiazepines, alcohol), physical and mental health (SF-36) or social functioning. Within each treatment group, significant reductions were observed in crime [SIH = odds ratio (OR) 0.05; P < 0.001; SIM = OR 0.11; P = 0.002; OOM = OR 0.11; P = 0.003] and money spent per week on illicit drugs (SIH = mean change £-289.43; P < 0.001; SIM = mean change £-183.41; P < 0.001; OOM = mean change £-162.80; P < 0.001), with SIH significantly more likely to have reduced money spent on illicit drugs versus OOM (mean difference £-92.04; P < 0.001). Significant improvements were seen in physical health for SIH and SIM (SIH = mean change 3.97; P = 0.008; SIM = mean change 4.73; P = 0.002) and mental health for OOM (mean change 6.04; P = 0.013). CONCLUSIONS Supervised injectable heroin treatment and supervised injectable methadone treatment showed no clearly identified benefit over optimized oral methadone in terms of wider drug use, crime, physical and mental health within a 6-month period, despite reducing street heroin use to a greater extent. However, all interventions were associated with improvements in these outcomes.


Contemporary Clinical Trials | 2018

Positive reinforcement targeting abstinence in substance misuse (PRAISe): Study protocol for a Cluster RCT & process evaluation of contingency management

Nicola Metrebian; Tim Weaver; Stephen Pilling; Jennifer Hellier; Sarah Byford; James Shearer; Luke Mitcheson; M. Astbury; P. Bijral; N. Bogdan; Owen Bowden-Jones; Ed Day; Joel Dunn; Emily Finch; S. Forshall; A. Glasper; G. Morse; Shabana Akhtar; J. Bajaria; Carmel Bennett; E. Bishop; Vikki Charles; C. Davey; R. Desai; C. Goodfellow; F. Haque; Nicholas Little; H. McKechnie; Joanna R. Morris; F. Mosler

There are approximately 256,000 heroin and other opiate users in England of whom 155,000 are in treatment for heroin (or opiate) addiction. The majority of people in treatment receive opiate substitution treatment (OST) (methadone and buprenorphine). However, OST suffers from high attrition and persistent heroin use even whilst in treatment. Contingency management (CM) is a psychological intervention based on the principles of operant conditioning. It is delivered as an adjunct to existing evidence based treatments to amplify patient benefit and involves the systematic application of positive reinforcement (financial or material incentives) to promote behaviours consistent with treatment goals. With an international evidence base for CM, NICE recommended that CM be implemented in UK drug treatment settings alongside OST to target attendance and the reduction of illicit drug use. While there was a growing evidence base for CM, there had been no examination of its delivery in UK NHS addiction services. The PRAISe trial evaluates the feasibility, acceptability, clinical and cost effectiveness of CM in UK addiction services. It is a cluster randomised controlled effectiveness trial of CM (praise and financial incentives) targeted at either abstinence from opiates or attendance at treatment sessions versus no CM among individuals receiving OST. The trial includes an economic evaluation which explores the relative costs and cost effectiveness of the two CM intervention strategies compared to TAU and an embedded process evaluation to identify contextual factors and causal mechanisms associated with variations in outcome. This study will inform UK drug treatment policy and practice. Trial registration ISRCTN 01591254.


British Journal of Psychiatry | 2003

Comorbidity of substance misuse and mental illness in community mental health and substance misuse services

Tim Weaver; P. Madden; Vikki Charles; Gerry V. Stimson; Adrian Renton; Peter Tyrer; Thomas R. E. Barnes; C. Bench; H. Middleton; N. Wright; S. Paterson; W. Shanahan; N. Seivewright; C. Ford


Drug and Alcohol Dependence | 2008

Researching the intoxicated: Informed consent implications for alcohol and drug research

Judith Aldridge; Vikki Charles


Drug and Alcohol Review | 2013

Treatment expectations and satisfaction of treatment-refractory opioid-dependent patients in RIOTT, the Randomised Injectable Opiate Treatment Trial, the UK's first supervised injectable maintenance clinics.

Teodora Groshkova; Nicola Metrebian; Christopher Hallam; Vikki Charles; Anthea Martin; Luciana Forzisi; Nicholas Lintzeris; John Strang


British Journal of Psychiatry | 2014

Effectiveness of methadone treatment for heroin addiction - Authors' Reply

Sarah Byford; Barbara Barrett; Nicola Metrebian; Teodora Groshkova; Maria Cary; Vikki Charles; Nicholas Lintzeris; John Strang

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John Strang

South London and Maudsley NHS Foundation Trust

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Teodora Groshkova

European Monitoring Centre for Drugs and Drug Addiction

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Nicholas Lintzeris

Royal College of Psychiatrists

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