Evins EA, Green AI, Kane JM, Murray RM.
Does using marijuana increase the risk for developing schizophrenia?. J Clin Psychiatry. 2013;74 (4) :e08.
AbstractAs more US states and other countries consider legalizing marijuana, clinicians need to know the possible effects of this drug. Research has shown a connection between marijuana use and an increased risk for schizophrenia in young people who are vulnerable to developing psychosis. An international panel of experts addresses topics such as risk factors for schizophrenia, the potency and effects of cannabis use on adolescents, the effects of concurrent drug use with cannabis on schizophrenia risk, and current attitudes toward marijuana.
Cather C, Dyer MA, Burrell HA, Hoeppner B, Goff DC, Evins EA.
An Open Trial of Relapse Prevention Therapy for Smokers With Schizophrenia. J Dual Diagn. 2013;9 (1) :87-93.
AbstractOBJECTIVE: Following successful smoking cessation, smokers with schizophrenia are vulnerable to relapse shortly after treatment discontinuation. Our objective was to assess the feasibility and effectiveness of a 12-month relapse prevention intervention in recently abstinent smokers with schizophrenia.
METHOD: Adult outpatient smokers with schizophrenia received weekly cognitive behavioral therapy groups, bupropion slow release, transdermal nicotine patch, and nicotine gum or lozenge for three months. Subjects with seven-day point prevalence abstinence at month 3 received an additional 12 months (months 4-15) of therapy with bupropion, transdermal nicotine patch, and nicotine gum/lozenge in conjunction with relapse prevention-based cognitive behavioral therapy groups that were held weekly in month 4, biweekly in months 5-6, and monthly in months 7-15.
RESULTS: Seventeen of 41 participants (41.5%) attained biochemically verified self-report of seven-day point prevalence abstinence at the end of three months of treatment and entered relapse prevention treatment. There was an 81% attendance rate at relapse prevention groups. At the end of the 12-month relapse prevention phase (month 15 overall), 11 of 17 (64.7%) demonstrated biochemically verified seven-day point prevalence abstinence, and 10 of 17 (58.8%) reported four-week continuous abstinence. Almost one quarter of the sample (23.5%) demonstrated long-term prolonged abstinence through the end of the trial. There were no clinically detected cases of psychiatric symptom exacerbation. One participant, who was managed as an outpatient, self-reported psychiatric symptom exacerbation in the interim period between study visits.
CONCLUSIONS: Extended duration smoking cessation treatment is well-tolerated and may improve smoking outcomes for recently abstinent smokers with schizophrenia. Controlled trials are warranted.
David SP, Lancaster T, Stead LF, Evins EA, Prochaska JJ.
Opioid antagonists for smoking cessation. Cochrane Database Syst Rev. 2013;6 :CD003086.
AbstractBACKGROUND: The reinforcing properties of nicotine may be mediated through release of various neurotransmitters both centrally and systemically. People who smoke report positive effects such as pleasure, arousal, and relaxation as well as relief of negative affect, tension, and anxiety. Opioid (narcotic) antagonists are of particular interest to investigators as potential agents to attenuate the rewarding effects of cigarette smoking.
OBJECTIVES: To evaluate the efficacy of opioid antagonists in promoting long-term smoking cessation. The drugs include naloxone and the longer-acting opioid antagonist naltrexone.
SEARCH METHODS: We searched the Cochrane Tobacco Addiction Group Specialised Register for trials of naloxone, naltrexone and other opioid antagonists and conducted an additional search of MEDLINE using 'Narcotic antagonists' and smoking terms in April 2013. We also contacted investigators, when possible, for information on unpublished studies.
SELECTION CRITERIA: We considered randomised controlled trials comparing opioid antagonists to placebo or an alternative therapeutic control for smoking cessation. We included in the meta-analysis only those trials which reported data on abstinence for a minimum of six months. We also reviewed, for descriptive purposes, results from short-term laboratory-based studies of opioid antagonists designed to evaluate psycho-biological mediating variables associated with nicotine dependence.
DATA COLLECTION AND ANALYSIS: We extracted data in duplicate on the study population, the nature of the drug therapy, the outcome measures, method of randomisation, and completeness of follow-up. The main outcome measure was abstinence from smoking after at least six months follow-up in patients smoking at baseline. Abstinence at end of treatment was a secondary outcome. We extracted cotinine- or carbon monoxide-verified abstinence where available. Where appropriate, we performed meta-analysis, pooling risk ratios using a Mantel-Haenszel fixed-effect model.
MAIN RESULTS: Eight trials of naltrexone met inclusion criteria for meta-analysis of long-term cessation. One trial used a factorial design so five trials compared naltrexone versus placebo and four trials compared naltrexone plus nicotine replacement therapy (NRT) versus placebo plus NRT. Results from 250 participants in one long-term trial remain unpublished. No significant difference was detected between naltrexone and placebo (risk ratio (RR) 1.00; 95% confidence interval (CI) 0.66 to 1.51, 445 participants), or between naltrexone and placebo as an adjunct to NRT (RR 0.95; 95% CI 0.70 to 1.30, 768 participants). The estimate was similar when all eight trials were pooled (RR 0.97; 95% CI 0.76 to 1.24, 1213 participants). In a secondary analysis of abstinence at end of treatment, there was also no evidence of any early treatment effect, (RR 1.03; 95% CI 0.88 to 1.22, 1213 participants). No trials of naloxone or buprenorphine reported abstinence outcomes.
AUTHORS' CONCLUSIONS: Based on data from eight trials and over 1200 individuals, there was no evidence of an effect of naltrexone alone or as an adjunct to NRT on long-term smoking abstinence, with a point estimate strongly suggesting no effect and confidence intervals that make a clinically important effect of treatment unlikely. Although further trials might narrow the confidence intervals they are unlikely to be a good use of resources.
Evins EA.
Reassessing the safety of varenicline. Am J Psychiatry. 2013;170 (12) :1385-7.