Biomedical subjects

Maxine L Stitzer

Publications and source records attributed to Maxine L Stitzer.

At least 19 recordsLinked to original sources

PubMed2007

Smoking in the absence of nicotine: behavioral, subjective and physiological effects over 11 days.

AIMS: Sensorimotor stimuli associated with tobacco smoking influence smoking behavior; however, current research has focused almost exclusively on the effects of brief, laboratory-based exposure to smoking-related stimuli. The purpose of this experiment was to characterize the effects of smoking stimuli delivered in the absence of nicotine over an extended (11-day) exposure. DESIGN, SETTING AND PARTICIPANTS: Thirty adult regular smokers participated in an in-patient study. After assessing preferred brand smoking, participants were assigned randomly to one of three groups corresponding to subsequent smoking conditions: nicotine-containing cigarettes, de-nicotinized cigarettes or no smoking. MEASUREMENTS: Measures of smoking reinforcement, subjective effects, physiological effects, withdrawal/craving and puff topography were taken repeatedly during both periods of free access and controlled assessments during abstinence. FINDINGS: Daily de-nicotinized cigarette use declined immediately by 1.7 cigarettes/day compared to the preferred brand baseline and declined by another 3.5 cigarettes over time; participants smoking de-nicotinized cigarettes also demonstrated a 31% decline in the number of puffs earned on a progressive ratio, a measure of the motivation to smoke, during the study. Subjective ratings of smoking were largely negative throughout the study in the de-nicotinized group, while the nicotine-containing condition reported increasingly positive subjective effects with repeated exposure. Acute craving suppression following smoking remained evident throughout the study regardless of nicotine content. CONCLUSIONS: These effects highlight the importance of non-nicotine sensorimotor stimuli as determinants of the maintenance of smoking behavior and suggests that extinction of conditioned reinforcement in the absence of nicotine progresses slowly.

Adolescent↗

PubMed2006

Prize-based contingency management does not increase gambling.

A contingency management (CM) intervention that provides drug-abstinent patients a chance to win prizes of varying magnitudes is efficacious in retaining patients in treatment and reducing drug use. However, this intervention has been criticized as possibly increasing gambling because it contains an element of chance. Gambling behaviors before, during and 3 months after participation in a multi-site study of CM were compared for stimulant users randomly assigned to 12 weeks of standard care with (N=407) or without (N=396) prize-based CM. Among study participants enrolled in outpatient non-methadone drug abuse treatment (N=415), 26% reported gambling during the observation period, and this rate was 37% among participants (N=388) enrolled in methadone maintenance programs. No differences in gambling over time were noted between those assigned to the prize CM versus standard care conditions, indicating that this prize CM procedure does not adversely impact gambling behavior among stimulant abusers.

Adult↗

PubMed2006

Effects of lower-cost incentives on stimulant abstinence in methadone maintenance treatment: a National Drug Abuse Treatment Clinical Trials Network study.

BACKGROUND: Contingency management interventions that provide tangible incentives based on objective indicators of drug abstinence have improved treatment outcomes of substance abusers, but have not been widely implemented in community drug abuse treatment settings. OBJECTIVE: To compare outcomes achieved when a lower-cost prize-based contingency management treatment is added to usual care in community methadone hydrochloride maintenance treatment settings. DESIGN: Random assignment to usual care with (n = 198) or without (n = 190) abstinence incentives during a 12-week trial. SETTING: Six community-based methadone maintenance drug abuse treatment clinics in locations across the United States. PARTICIPANTS: Three hundred eighty-eight stimulant-abusing patients enrolled in methadone maintenance programs for at least 1 month and no more than 3 years. INTERVENTION: Participants submitting stimulant- and alcohol-negative samples earned draws for a chance to win prizes; the number of draws earned increased with continuous abstinence time. MAIN OUTCOME MEASURES: Total number of stimulant- and alcohol-negative samples provided, percentage of stimulant- and alcohol-negative samples provided, longest duration of abstinence, retention, and counseling attendance. RESULTS: Submission of stimulant- and alcohol-negative samples was twice as likely for incentive as for usual care group participants (odds ratio, 1.98; 95% confidence interval, 1.42-2.77). Achieving 4 or more, 8 or more, and 12 weeks of continuous abstinence was approximately 3, 9, and 11 times more likely, respectively, for incentive vs usual care participants. Groups did not differ on study retention or counseling attendance. The average cost of prizes was 120 dollars per participant. CONCLUSION: An abstinence incentive approach that paid 120 dollars in prizes per participant effectively increased stimulant abstinence in community-based methadone maintenance treatment clinics.

Adult↗

PubMed2006

Experimental evidence for a causal relationship between smoking lapse and relapse.

In this study, the authors prospectively evaluated the impact of a smoking lapse on relapse probability. After 4 days of smoking abstinence, 60 smokers were randomly assigned to smoke 5 nicotine-containing or 5 denicotinized cigarettes, or to remain abstinent (no lapse) during a 4-hr time period. Afterward, smoking abstinence was encouraged with monetary incentives, and smoking behavior was tracked for 6 days. Relative to the no-lapse condition, exposure to either of the cigarette types more than doubled the probability of subsequent smoking. Smoking outcomes did not differ between nicotine-containing and denicotinized cigarettes. The data suggest that stimulus factors may play an important role in lapse to relapse processes.

Adult↗

PubMed2006

A preliminary investigation of rapid smoking as a lapse-responsive treatment for tobacco dependence.

Lapses within the first 2 weeks of a smoking cessation attempt are strongly associated with a return to regular smoking (S. L. Kenford et al., 1994). Unfortunately, little is known about how to prevent an initial lapse from progressing to a full relapse, and presently there are no validated lapse-responsive therapeutic interventions. The present study tested the efficacy and feasibility of rapid smoking plus counseling as a novel lapse-responsive intervention. Sixty-seven participants enrolled in a smoking treatment program involving brief counseling and a 9-week course of bupropion. Beginning on the quit day, participants' smoking behavior was tracked daily for 14 days. Once an early smoking lapse was identified, participants were randomly assigned to receive either 3 sessions of rapid smoking plus counseling or no intervention (usual care). Consistent with previous research, participants who smoked during the first 2 weeks of the quit attempt had significantly poorer 6-month outcomes (3% abstinent) than did those who did not smoke (64% abstinent). Compared with early abstainers, early lapsers were more nicotine dependent and reported greater cravings and lower confidence in their ability to abstain from smoking during the first 48 hours of abstinence. As expected, rapid smoking produced a variety of aversive effects, including increased nausea, dizziness, and vomiting as well as sharply decreased cravings to smoke. However, rapid smoking did not improve abstinence outcomes relative to usual care. Although rapid smoking has been shown to be an effective treatment for initial smoking cessation, in this preliminary study the authors failed to demonstrate its effectiveness as a lapse-responsive treatment.

Adult↗

PubMed2006

Expired carbon monoxide levels in self-reported smokers and nonsmokers in prison.

Breath carbon monoxide (CO) is a convenient, widely used method for abstinence validation, with cutoffs of 8-10 ppm commonly employed. The goal of the present study was to determine an appropriate CO cutoff to differentiate nonsmokers and smokers within a large sample (N = 374) of female prisoners incarcerated at a correctional facility in Virginia. Mean age of the population was 34.5 years, 49.2% were White, and 29% had less than a high school education. Smoking prevalence was 74.1% within the prison population. Examination of CO levels versus smoking self-report using a receiver operator characteristic (ROC) analysis revealed that a CO cutoff of 3 ppm resulted in the best sensitivity (98.1%) and specificity (95.8%). Overall ROC area under the curve was 99% (95% CI = 98.2%-99.9%). This same cutoff was optimal for smoking subgroups including Black and light (<10 cigarettes/day) smokers. Results suggest that CO cutoffs higher than 3 ppm may misclassify some smokers as nonsmokers and underestimate the prevalence of smoking.

Adult↗

PubMed2006

Contingency management for the treatment of methamphetamine use disorders.

OBJECTIVE: Theory and some preliminary evidence suggest that contingency management may be an effective treatment strategy or adjunct to psychosocial treatment for methamphetamine use disorders. An experimentally rigorous investigation on the topic was provided by a large multisite trial conducted under the auspices of the Clinical Trials Network of the National Institute on Drug Abuse. METHOD: The authors report data on 113 participants who were diagnosed with methamphetamine abuse or dependence. They were randomly assigned to receive 12 weeks of either treatment as usual or treatment as usual plus contingency management. Urine samples were tested for illicit drugs, and breath samples were tested for alcohol. The reinforcers for drug-negative samples were plastic chips, some of which could be exchanged for prizes. The number of plastic chips drawn increased with each week of negative samples but was reset to one after a missed or positive sample. RESULTS: The participants in both groups remained in treatment for equivalent times, but those receiving contingency management in addition to usual treatment submitted significantly more negative samples, and they were abstinent for a longer period of time (5 versus 3 weeks). CONCLUSIONS: These results suggest that contingency management has promise as a component in treatment strategies for methamphetamine use disorder.

Adult↗

PubMed2005

Reinforcement-based therapy: 12-month evaluation of an outpatient drug-free treatment for heroin abusers.

This controlled study examined the efficacy of reinforcement-based therapy (RBT) for producing enhanced abstinence outcomes over 12 months in opioid-dependent patients exiting a brief residential detoxification. Patients were randomly assigned upon completing their medically managed taper (i.e., detoxification) to RBT (N=66) or usual care (N=64) referral to community treatment programs. The 6-month RBT program offered an array of abstinence-based incentives including rent payment for recovery housing, program-led recreational activities and skills training for procuring employment. RBT produced significantly higher self-report and urinalysis-confirmed rates of abstinence from opioids and cocaine relative to usual care at 1 (42% versus 15%) and 3 (38% versus 17%) months during treatment but not at 6 or 12 months after enrollment. The RBT but not the usual care group showed significant increases in the number of days worked and the amount of legal income earned at 3, 6 and 12 months. The results of this randomized study suggest that an intensive reinforcement-based therapy that includes abstinence-based recovery housing is a promising approach; however, further research is needed to determine the role of treatment intensity and the specific efficacy of RBT's component parts.

Adult↗

PubMed2005

Effect of prize-based incentives on outcomes in stimulant abusers in outpatient psychosocial treatment programs: a national drug abuse treatment clinical trials network study.

CONTEXT: Contingency management interventions that provide tangible incentives based on objective indicators of drug abstinence are efficacious in improving outcomes in substance abusers, but these treatments have rarely been implemented in community-based settings. OBJECTIVE: To evaluate the efficacy of an abstinence-based contingency management intervention as an addition to usual care in community treatment settings. DESIGN: Random assignment to usual care or usual care plus abstinence-based incentives for 12 weeks. SETTING: Eight community-based outpatient psychosocial drug abuse treatment programs. PARTICIPANTS: A total of 415 cocaine or methamphetamine users beginning outpatient substance abuse treatment. INTERVENTION: All participants received standard care, and those assigned to the abstinence-based incentive condition also earned chances to win prizes for submitting substance-free urine samples; the chances of winning prizes increased with continuous time abstinent. MAIN OUTCOME MEASURES: Retention, counseling attendance, total number of substance-free samples provided, percentage of stimulant- and alcohol-free samples submitted, and longest duration of confirmed stimulant abstinence. RESULTS: Participants assigned to the abstinence-based incentive condition remained in treatment for a mean +/- SD of 8.0 +/- 4.2 weeks and attended a mean +/- SD of 19.2 +/- 16.8 counseling sessions compared with 6.9 +/- 4.4 weeks and 15.7 +/- 14.4 sessions for those assigned to the usual care condition (P<.02 for all). Participants in the abstinence-based incentive condition also submitted significantly more stimulant- and alcohol-free samples (P<.001). The abstinence-based incentive group was significantly more likely to achieve 4, 8, and 12 weeks of continuous abstinence than the control group, with odds ratios of 2.5, 2.7, and 4.5, respectively. However, the percentage of positive samples submitted was low overall and did not differ between conditions. CONCLUSION: The abstinence-based incentive procedure, which provided a mean of 203 dollars in prizes per participant, was efficacious in improving retention and associated abstinence outcomes.

Adult↗

PubMed2005

Use of a low-cost incentive intervention to improve counseling attendance among methadone-maintained patients.

Despite the importance of counseling in methadone maintenance treatment, many patients do not take advantage of these services. Incentives for attending group counseling were offered to methadone-maintained patients during an orientation phase of treatment or during required attendance at a relapse group later in treatment. Upon attending each counseling session, patients could draw for prizes under an escalating draw system with a 50% probability that draws would result in a prize. Incentives included small (1dollar), moderate (5 dollars), and large (20 dollars) prizes, with chances of winning inversely related to prize costs, and a maximum possible total of 160 dollars per patient. It was anticipated that this policy would provide a relatively low-cost approach to improving counseling attendance in our methadone clinic. The incentive policy significantly increased the percent of counseling sessions attended (52% vs. 76%) and promoted periods of continuous attendance. These data further support the effectiveness of low-cost incentive programs in enhancing counseling attendance among methadone patients.

Adult↗

PubMed2005

Cash value of voucher reinforcers in pregnant drug-dependent women.

This study examined the relative reinforcing potency of vouchers and cash in drug-dependent pregnant women (N = 48) across voucher values (US 10 dollars, US 50 dollars, and US 100 dollars) by use of a series of choices to understand how exchange-delay features of voucher reinforcers influence their reinforcing potency compared with cash. The study also examined a no delay vs. 2-day delay of the cash alternative. Generally, cash was selected at 80%-90% of voucher face values. Vouchers were also discounted less when a 2-day delay was imposed on the cash option compared to the immediately available cash. These results suggest that voucher discounting does occur among patients in drug treatment. However, vouchers retain 80%-90% of their cash value and thus remain relatively potent reinforcers.

Adult↗

PubMed2005

A comparison of voucher-delivery schedules for the initiation of cocaine abstinence.

Studies on the use of shaping procedures to increase rates of cocaine abstinence have produced promising results. This study used a Brief Abstinence Test to examine the impact of reinforcement for initial reductions in cocaine use on a subsequent abstinence reinforcement test. Methadone maintenance patients showing evidence of cocaine use were exposed to two 1-week reinforcement conditions. During the shaping condition, participants could earn $50 vouchers on Wednesday and Friday for meeting quantitative urinalysis criteria and a $100 voucher on the following Monday for meeting the more stringent qualitative criteria. During the terminal condition, only the $100 earning opportunity for meeting the qualitative criteria was provided. Participants were more likely to meet the qualitative reinforcement criteria on Wednesday and Friday in the shaping condition than in the terminal condition. However, contrary to the initial hypothesis, the shaping reinforcement condition did not increase rates of abstinence on the final abstinence test.

Adult↗

PubMed2005

Methadone doses of 100 mg or greater are more effective than lower doses at suppressing heroin self-administration in opioid-dependent volunteers.

AIMS: Methadone maintenance has been an effective pharmacotherapy for the treatment of heroin dependence for nearly four decades. Recent clinical research suggests that methadone doses larger than those used in most clinics are more effective at suppressing illicit heroin use. This greater efficacy may result from greater cross-tolerance to the reinforcing effects of heroin. DESIGN: The purpose of this double-blind, within-subject study was to examine the relationship between methadone maintenance dose and the reinforcing effects of heroin. SETTING: Participants were stabilized on 50, 100 and 150 mg methadone (ascending order) during separate outpatient periods before being admitted to an inpatient research unit for testing at each maintenance dose. PARTICIPANTS: Five opiate-dependent volunteers completed the study. MEASUREMENTS: During each 4-week inpatient testing period, participants sampled three doses of heroin (0, 10, or 20 mg; random order; one dose per week) and were subsequently allowed seven opportunities to choose between another injection of that week's heroin dose and varying amounts of money (dollars 2-38). FINDINGS: The number of heroin injections chosen decreased as methadone dose was increased. Larger alternative monetary reinforcers were required to suppress heroin self-administration during maintenance on 50 compared to 100 or 150 mg methadone. Larger methadone doses also completely blocked the subjective effects of heroin and produced greater withdrawal suppression during the outpatient periods. CONCLUSIONS: These results support other clinical and laboratory-based research indicating that persistent heroin use may be reduced by providing larger methadone maintenance doses that produce more effective cross-tolerance to heroin.

Adult↗

PubMed2004

Opioid abuse and cognitive performance.

A few recent studies provide evidence for performance impairment in dependent opioid abusers enrolled in methadone maintenance programs. However, it is difficult to differentiate the effects of a history of long-term opioid (or polydrug) abuse from the effects of methadone maintenance itself. The purpose of the present study was to address this issue by comparing the performance of a newly recruited group of 20 currently abstinent former opioid abusers retrospectively to two groups (18 methadone maintenance patients (MMP); 21 matched non-drug abusing controls) reported on previously in our laboratory [Mintzer, M.Z., Stitzer, M.L., 2002. Cognitive impairment in methadone maintenance patients. Drug Alcohol Depend. 67, 41-51], using the same performance testing battery. The abstinent abusers were demographically similar to the MMP and matched controls, and reported histories of drug use similar to those of the MMP. Although conclusions are somewhat limited by the small sample size, performance of the abstinent abusers fell between that of the MMP and controls on many measures, suggesting that methadone maintenance may be associated with additional impairment over and above that associated with long-term abuse, and that recovery of functioning may occur during abstinence. Further research is necessary to explore the factors underlying performance impairment in MMP and to determine the clinical significance of the observed impairments for daily performance in the natural environment.

Adult↗

PubMed2004

Identifying pregnant women at risk for early attrition from substance abuse treatment.

Greater treatment retention among pregnant substance abusers is associated with improved pregnancy and neonatal outcomes, so early identification of clients most at risk for early attrition is essential. Participants were 152 pregnant women enrolled in the initial 7-day residential component of a comprehensive substance abuse treatment program for pregnant women. Twenty-nine (19%) women left treatment within the first 5 days, primarily within the first 2 days. Clinical staff identified many, but not all, patients who eventually left treatment early as many indicated their desire to leave and were troubled by drug craving and withdrawal. Other predictors of attrition included not receiving methadone maintenance, being Caucasian, and reporting more prior drug treatment episodes, fewer medical problems and, to a lesser extent, more family/social and psychiatric and fewer drug problems on the Addiction Severity Index. Interventions are needed to target pregnant clients most at risk for early treatment attrition.

Adolescent↗

PubMed2004

A randomized trial of long-term reinforcement of cocaine abstinence in methadone-maintained patients who inject drugs.

This study determined whether long-term abstinence reinforcement could maintain cocaine abstinence throughout a year long period. Patients who injected drugs and used cocaine during methadone treatment (n = 78) were randomly assigned to 1 of 2 abstinence-reinforcement groups or to a usual care control group. Participants in the 2 abstinence-reinforcement groups could earn take-home methadone doses for providing opiate- and cocaine-free urine samples; participants in 1 of those groups also could earn 5,800 US dollars in vouchers for providing cocaine-free urine samples over 52 weeks. Both abstinence-reinforcement interventions increased cocaine abstinence, but the addition of the voucher intervention resulted in the largest and most sustained abstinence. Therefore, voucher-based reinforcement of cocaine abstinence in methadone patients can be a highly effective maintenance intervention.

Adolescent↗

PubMed2004

Cocaine abstinence during methadone maintenance: effects of repeated brief exposure to voucher-based reinforcement.

This study determined whether abstinence engendered by intermittent reinforcement might generalize to nonreinforced periods and enhance overall rates of cocaine abstinence among methadone maintenance patients. Participants were randomized to 1 of 3 groups. The quantitative group (n = 14) earned incentives for a 50% decrease in urine benzoylecgonine concentrations; the qualitative group (n = 13) earned incentives for providing urines with concentrations <300 ng/ml. Both reinforced groups received 12 random opportunities to earn 100 US dollars in vouchers for abstinence. The control group (n = 15) was encouraged to abstain on 12 occasions under the same schedule. Incentive participants achieved significantly more cocaine abstinence on earning than on nonearning days, with no difference between quantitative and qualitative groups. The study supports brief abstinence test efficacy but did not find that unpredictable opportunities to earn incentives generalized to nonreinforced days.

Adult↗

PubMed2003

Subjective effects of the nicotine lozenge: assessment of abuse liability.

RATIONALE: A nicotine lozenge was developed as a novel smoking cessation aid. Abuse liability, which in this context refers to use by novices not addicted to tobacco, may be expected to be low for the lozenge due to the relatively slow route of nicotine absorption. However, its resemblance to commercially marketed lozenges and its palatability, intended to increase medication compliance, may increase its abuse liability, especially among younger individuals. OBJECTIVES: The present study evaluated the abuse liability of the nicotine lozenge. Effects of the lozenge on cigarette craving were also measured. METHODS: Subjective and physiological effects of the nicotine lozenge were tested in healthy adult smokers ( n=12, 22-55 years old); a group of younger subjects ( n=12, 18-21 years) was also included to allow for assessment of abuse liability of the lozenge in young adults specifically. Amphetamine and a confectionery lozenge were included in the study conditions as positive controls for abuse liability and palatability, respectively, and nicotine gum was included to allow for comparison with a marketed oral nicotine replacement product with low abuse liability. RESULTS: The nicotine lozenge did not increase ratings of traditional abuse liability predictors (good effect, like effect, MBG scale of the ARCI), while amphetamine significantly increased ratings on these measures. The lozenge dose dependently decreased craving for cigarettes after 70 min of abstinence, but only in the older group. Palatability of the lozenge was rated lower than a confectionery lozenge, but not lower than nicotine mint gum. CONCLUSIONS: Results suggest that the nicotine lozenge has low abuse liability, both in adults and young adults. The lozenge reduces craving to smoke, although craving reduction may not apply to young adults (18-21 years). Subjective effects of the lozenge are consistent with utility as a smoking cessation aid and are comparable to those of nicotine gum.

Adolescent↗