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Biomedical subjects

David H Epstein

Publications and source records attributed to David H Epstein.

8 recordsLinked to original sources
PubMed2003

The reinstatement model and relapse prevention: a clinical perspective.

OBJECTIVES: This commentary assesses the degree to which the reinstatement model is homologous to the human experience of relapse. RESULTS: A review of the literature suggests that the relationship is less clear than is often assumed, largely due to a lack of prospective data on the precipitants and process of relapse (especially relapse to heroin or cocaine abuse). However, reinstatement does not need to resemble relapse to have immediate clinical value; predictive validity as a medication screen would be sufficient. Whether the model has predictive validity is unknown, because, to date, very few clinical trials have tested medications that are effective in the reinstatement model, and even fewer have used designs comparable to those of reinstatement experiments. A clinical trial comparable to a reinstatement experiment would enroll participants who are already abstinent, and its main outcome measure would be propensity to undergo a specific type of relapse (e.g., relapse induced by stress or cues). CONCLUSIONS: Until clinical and preclinical work are more comparable, criticisms of the reinstatement model's presumed shortcomings are premature.

Animals↗
PubMed2003

Cognitive-behavioral therapy plus contingency management for cocaine use: findings during treatment and across 12-month follow-up.

Contingency management (CM) rapidly reduces cocaine use, but its effects subside after treatment. Cognitive-behavioral therapy (CBT) produces reductions months after treatment. Combined, the 2 might be complementary. One hundred ninety-three cocaine-using methadone-maintained outpatients were randomly assigned to 12 weeks of group therapy (CBT or a control condition) and voucher availability (CM contingent on cocaine-negative urine or noncontingent). Follow-ups occurred 3, 6, and 12 months posttreatment. Primary outcome was cocaine-negative urine (urinalysis 3 times/week during treatment and once at each follow-up). During treatment, initial effects of CM were dampened by CBT. Posttreatment, there were signs of additive benefits, significant in 3- versus 12-month contrasts. Former CBT participants were also more likely to acknowledge cocaine use and its effects and to report employment.

Adult↗
PubMed2003

Do noncontingent vouchers increase drug use?

Data from 2 contingency management trials, targeting opiate or cocaine use, were used to investigate whether noncontingent vouchers inadvertently reinforce drug use. The control group in each trial received noncontingent vouchers matched in value and frequency to those received by experimental groups, but independent of urinalysis. Vouchers were offered thrice weekly for 8 weeks (opiates) or 12 weeks (cocaine). Both dose-response and temporal associations of noncontingent voucher receipt with drug-positive urines were assessed. Drug use was unrelated to frequency of noncontingent voucher delivery and noncontingent voucher receipt when being drug positive was unassociated with risk of subsequent drug use, with one exception: cocaine use in the cocaine study (relative risk = 1.05, 95% confidence interval: 1.01-1.09). Overall, results do not indicate a causal relationship between noncontingent voucher receipt and increased drug use.

Adult↗
PubMed2003

A factor analysis of the Fagerström Test for Nicotine Dependence (FTND).

Psychometric study of the Fagerström Test for Nicotine Dependence (FTND) provides insight into its structure and the dimensions of nicotine addiction it assesses. We evaluated the factor structure of the FTND in 541 research volunteers, most with histories of polysubstance use. Tetrachoric and phi correlation techniques were utilized and promax- and varimax-rotated solutions are reported. Two factors were found. Factor 1 was defined by questions regarding time to first cigarette in after waking, which cigarette is most preferred, and prominence of morning smoking. Factor 2 was defined by questions regarding difficulty refraining from smoking, amount smoked, and smoking while ill. The question "How soon on waking do you smoke your first cigarette?" loaded substantially on both Factor 2 and Factor 1. Repeating the analyses after stratification by gender did not change the results. The factor structure from our sample population was similar to results reported by previous studies with different types of populations. We propose that Factor 1 assesses the degree of urgency to restore nicotine levels to a given threshold after nighttime abstinence, whereas Factor 2 reflects the persistence with which nicotine levels are maintained at about that threshold during waking hours. Thus, the FTND may assess distinguishable self-reportable pharmacological dimensions of nicotine addiction. These two dimensions may provide indirect assessment of a smoker's daily nicotine intake. Testing this hypothesis requires correlation of biomarkers and responses to specific items of the FTND.

Adolescent↗
PubMed2002

Abstinence reinforcement maintenance contingency and one-year follow-up.

BACKGROUND: Relapse to drug use is often seen when contingencies designed to reduce drug use are discontinued. This paper reports on a stepdown maintenance contingency and 1-year follow-up in 110 patients who were maintained on methadone (50 or 70 mg/day) and who had completed a contingency management trial targeted to decreasing their opiate use. In the prior study (induction phase, 8 weeks) participants received vouchers for each opiate-negative urine screen or noncontingently. METHODS: In this study (maintenance phase, 12 weeks), participants were rerandomized to receive vouchers and take-home methadone doses contingent on providing opiate-negative urine specimens (N=55) or noncontingently (N=55). Since participants had been rerandomized from induction-phase contingencies, most study data were analyzed as if from a 2 x 2 (inductionxmaintenance) design. Follow-up interviews were conducted at 3, 6, and 12 months after study participation. RESULTS: Patients who received the maintenance contingency following an 8-week induction contingency had better outcomes than those who received noncontingent incentives in either the maintenance or induction phases of the trial. Good outcome at follow-up was predicted by enrollment in methadone maintenance after the study. Significantly more participants in the maintenance contingency group transferred directly to another methadone program. CONCLUSION: These findings support the therapeutic value of extending the duration of contingency management and long-term methadone maintenance.

Adult↗
PubMed2002

Urinary elimination of cocaine metabolites in chronic cocaine users during cessation.

We previously showed that chronic cocaine use by active illicit users produced a longer plasma half-life than expected based on acute low-dose cocaine studies. Here we report urinary excretion patterns of cocaine metabolites as benzoylecgonine (BE) equivalents from 18 of the same individuals, housed for up to 14 days on a closed research unit. In addition, we evaluated whether creatinine normalization of BE equivalents increased mean detection time and reduced mean within-subject variability. All urine voids (N = 953) were individually assayed; BE equivalents were determined semi-quantitatively by FPIA. Compared to concentration in first void after admission, BE equivalents decreased to approximately 33%, 8%, and 4% at 24, 48, and 72 h, respectively. Mean +/- SD (range) time to first negative specimen (BE equivalents < 300 ng/mL) was 43.6 +/- 17.1 (16-66) h. BE equivalents fluctuated considerably across successive specimens; 69% of participants tested positive at least once after testing negative, and the mean time to last positive specimen was 57.5 +/- 31.6 (11-147) h after the first specimen. Thus, mean cocaine metabolite detection times were consistent with prolonged elimination, with 63% of participants testing positive longer than the expected 48-h window of detection after admission to the unit. Mean time to last positive after last use of cocaine, known by self-report only, was approximately 81 +/- 34 (34-162) h. Creatinine normalization, with the cut-off of 300 ng BE equivalents/mg creatinine, increased detection time: mean time to first negative specimen was 54.8 +/- 20.7 (20-100) h, and mean time to last positive specimen was 88.4 +/- 51.0 (35.6-235) h. Compared with the concentration in the first void after admission, BE equivalents/creatinine decreased to approximately 56%, 6%, and 5% at 24, 48, and 72 h. However, creatinine normalization did not reduce the fluctuation of BE equivalents across successive specimens. Thus, creatinine normalized values may be useful when the goal is to maximize the probability or duration of cocaine metabolite detection, but may be less useful in determining whether an individual has used cocaine since a previous specimen collection.

Adult↗
PubMedDate not supplied

The Fagerstrom Test for Nicotine Dependence and the Diagnostic Interview Schedule: do they diagnose the same smokers?

Two common assessment tools for nicotine dependence are the Fagerstrom Test for Nicotine Dependence (FTND) and the Nicotine Dependence section of the Diagnostic Interview Schedule [(DIS)-III-R or -IV based on the Diagnostic and Statistical Manual (DSM)-III-R and -IV, respectively]. The FTND emphasizes morning smoking and overall "heaviness" of smoking. The DSM emphasizes adverse consequences, desire to cut down, and mood changes during withdrawal. We tested (1) how the DSM-III-R diagnosis of Nicotine Dependence is related to FTND score; and (2) how the (a) DSM-III-R or (b) elevated FTND score is related to longer smoking histories, greater psychiatric symptomatology, and tobacco liking scores. Retrospective chart reviews were conducted on 370 smokers, the majority (55.9%) of whom had a current DSM-III-R diagnosis of Substance Dependence other than nicotine. All subjects had completed the FTND, the DIS-III-R, the Symptom Checklist-90-Revised (SCL-90-R), and a survey on drug liking. Agreement statistics were calculated between the DSM-II-R diagnosis of Nicotine Dependence and various cutoff scores values that were assigned as thresholds for nicotine dependence on the FTND. At no cutoff score did the two instruments reliably agree; the highest kappa (at a cutoff of FTND > or = 7) was 0.205. At cutoffs above 5, the FTND diagnosed fewer cases than the DSM-III-R. Multiple regression analysis showed that DSM diagnosis was associated with greater psychiatric symptomatology on the SCL-90-R, while FTND scores were associated with greater tobacco liking. The FTND and the DSM-III-R appear to measure different aspects of the tobacco dependence process. Specifically, the FTND may provide a stronger measure of physical dependence, while the DSM may tap other domains such as awareness of dependence, behaviors resulting from that awareness, and psychiatric symptomatology. Disagreements between the FTND and the DSM are likely to become greater with the changes in the DSM-IV.

Adolescent↗