Treatment of cocaine and alcohol dependence with psychotherapy and disulfiram

Aims. To evaluate disulfiram and three forms of manual guided psychotherapy for individuals with cocaine dependence and concurrent alcohol abuse or dependence. Design. Randomized controlled trial. Setting. Urban substance abuse treatment center. Participants. One hundred and twenty-two cocaine/alcohol abusers (27% female; 61% African-American or Hispanic). Interventions. One of five treatments delivered over 12 weeks: cognitive behavioral treatment (CBT) plus disulfiram; Twelve Step facilitation (TSF) plus disulfiram; clinical management (CM) plus disulfiram; CBT plus no medication; TSF plus no medication. Measurements. Duration of continuous abstinence from cocaine or alcohol; frequency and quantity of cocaine and alcohol use by week, verified by urine toxicology and breathalyzer screens. Findings. Disulfiram treatment was associated with significantly better retention in treatment, as well as longer duration of abstinence from alcohol and cocaine use. The two active psychotherapies (CBT and TSF) were associated with reduced cocaine use over time compared with supportive psychotherapy (CM). Cocaine and alcohol use were strongly related throughout treatment, particularly for subjects treated with disulfiram. Conclusions. For the large proportion of cocaine-dependent individuals who also abuse alcohol, disulfiram combined with outpatient psychotherapy may be a promising treatment strategy. This study underlines (a) the significance of alcohol use among treatment-seeking cocaine abusers, (b) the promise of the strategy of treating co-morbid disorders among drug-dependent individuals, and (c) the importance of combining psychotherapy and pharmacotherapy in the treatment of drug use disorders.     

High‐Dose Naltrexone Therapy for Cocaine‐Alcohol Dependence

This randomized, double‐blind, placebo‐controlled study compared the effects of high‐dose (100 mg/d) naltrexone versus placebo in a sample of 87 randomized subjects with both cocaine and alcohol dependence. Medication conditions were crossed with two behavioral therapy platforms that examined whether adding contingency management (CM) that targeted cocaine abstinence would enhance naltrexone effects compared to cognitive behavioral therapy (CBT) without CM. Primary outcome measures for cocaine (urine screens) and alcohol use (timeline followback) were collected thrice‐weekly during 12 weeks of treatment. Retention in treatment and medication compliance rates were low. Rates of cocaine use and drinks per day did not differ between treatment groups; however naltrexone did reduce frequency of heavy drinking days, as did CBT without CM. Notably, adding CM to CBT did not enhance treatment outcomes. These weak findings suggest that pharmacological and behavioral interventions that have shown efficacy in the treatment of a single drug dependence disorder may not provide the coverage needed when targeting dual drug dependence.     

Coadministration of disulfiram and lorazepam in the treatment of alcohol dependence and co-occurring anxiety disorder: an open-label pilot study

ABSTRACT

Background: Anxiety is common among persons with alcohol use disorder during early abstinence from alcohol. Although benzodiazepines are effective for short-term treatment of anxiety, they are rarely used beyond acute detoxification due to concerns about misuse or interactions with alcohol. Objectives: We conducted an open-label trial to explore the effects of coadministering lorazepam and disulfiram to alcohol-dependent patients with anxiety disorder symptoms. The rationale for this model is to minimize the risks of the benzodiazepine, while also potentially enhancing adherence to disulfiram. Methods: Forty-one participants with DSM-IV alcohol dependence who also met syndromal criteria for anxiety disorder with or without co-occurring major depressive syndrome initiated treatment with lorazepam (starting dose 0.5 mg three times daily) and disulfiram (starting dose 500 mg three times weekly). Participants received 16 weeks of monitored pharmacotherapy with manualized medical management. Results: Adherence to treatment decreased steadily with time (85.4% at 4 weeks, 36.6% at 16 weeks). Participants showed significant increases in percent abstinent days during treatment and at 24 weeks follow-up. Large reductions in anxiety, depression, and craving were observed during treatment, and improvement remained significant at 24 weeks. Duration of adherence with disulfiram strongly predicted abstinence at 16 weeks. There was no evidence of misuse of lorazepam or dose escalation during the study. Conclusion: Lorazepam can be safely used for short-term treatment of anxiety in combination with disulfiram treatment of alcohol use disorder. However, it is not clear that making lorazepam dispensing contingent on adherence to disulfiram enhances retention in disulfiram treatment.     

Pharmacologic Interventions for Alcohol- and Cocaine-Abusing Individuals

Eighteen outpatients dependent on both cocaine and alcohol were randomly assigned to disulfiram or naltrexone in an open pilot study. Disulfiram treatment resulted in significantly fewer days of alcohol and cocaine use, with longer sustained periods of abstinence from both substances.     

Crack cocaine, alcohol, and other drug use patterns among homeless persons with other mental disorders

This study examined the co-occurrence of cocaine, alcohol, marijuana, and other drug use among treatment seeking homeless persons to determine whether alcohol use predicted cocaine use differently than marijuana and other drugs predicted cocaine use. Participants were 141 homeless persons with substance use and other nonpsychotic mental disorders seeking drug treatment at a metropolitan health care agency for homeless persons. They were 72.3% male, 27.7% female, 82.7% African American, 17.3% Caucasian, with an average age of 37.7 (SD 7.1) years and had 13.1 (SD 2.4) average years of education. Results supported the assertion that cocaine use was strongly associated with extent of alcohol use and that the association between cocaine and alcohol was stronger than the association between cocaine and other drug use, including marijuana. Participants with cocaine plus alcohol disorders were retained longer in treatment than disorders of cocaine only with no differences in abstinence outcome. The findings should drive further research into the use of alcohol as a trigger or predictor of cocaine use, the deleterious effects of the combined use of cocaine and alcohol, and specialized treatments for polysubstance users.     

CRACK COCAINE,ALCOHOL, AND OTHER DRUG USE PATTERNS AMONG HOMELESS PERSONS WITH OTHER MENTAL DISORDERS

This study examined the co-occurrence of cocaine, alcohol, marijuana, and other drug use among treatment seeking homeless persons to determine whether alcohol use predicted cocaine use differently than marijuana and other drugs predicted cocaine use. Participants were 141 homeless persons with substance use and other nonpsychotic mental disorders seeking drug treatment at a metropolitan health care agency for homeless persons. They were 72.3% male, 27.7% female, 82.7% African American, 17.3% Caucasian, with an average age of 37.7 (SD 7.1) years and had 13.1 (SD 2.4) average years of education. Results supported the assertion that cocaine use was strongly associated with extent of alcohol use and that the association between cocaine and alcohol was stronger than the association between cocaine and other drug use, including marijuana. Participants with cocaine plus alcohol disorders were retained longer in treatment than disorders of cocaine only with no differences in abstinence outcome. The findings should drive further research into the use of alcohol as a trigger or predictor of cocaine use, the deleterious effects of the combined use of cocaine and alcohol, and specialized treatments for polysubstance users.     

Alcohol use affects the outcome of treatment for cocaine abuse

This study investigated whether alcohol use affects baseline characteristics and treatment outcome in 128 adults who participated in a randomized trial of cognitive behavioral vs. 12-step treatment for crack cocaine abuse. Assessments were taken at baseline and weeks 4, 8, 12, and 26 on biologically-verified cocaine abstinence and psychometric measures. Alcohol use was measured at intake and subsequent assessments using the Addiction Severity Index (ASI) and self-reported frequency of alcohol consumption. Results indicate alcohol use at baseline was associated with increased baseline cocaine use and ASI drug severity but was not associated with ASI psychiatric severity, psychiatric diagnoses, or other baseline variables. Alcohol use at baseline did not predict worse treatment outcome for cocaine abstinence. However, alcohol use after four weeks of treatment did predict ability to achieve cocaine abstinence at assessment points during and after treatment.     

A comparison of contingency management and cognitive-behavioral approaches for stimulant-dependent individuals

AIMS: Previous research has reported that both contingency management (CM) and cognitive-behavioral therapy (CBT) are efficacious interventions for the treatment of stimulant abusers. The present study sought to directly compare the effectiveness of (CM) and (CBT) alone and in combination in reducing stimulant use. DESIGN: Randomized clinical trial. PARTICIPANTS: Stimulant-dependent individuals (n = 171). INTERVENTION: CM, CBT or combined CM and CBT, 16-week treatment conditions. CM condition participants received vouchers for stimulant-free urine samples. CBT condition participants attended three 90-minute group sessions each week. MEASUREMENTS: Participants were interviewed at baseline and weeks 17, 26 and 52. Measures included psychiatric disorders and alcohol and drug use and concomitant social problems. FINDINGS: CM procedures produced better retention and lower rates of stimulant use during the study period. Self-reported stimulant use was reduced from baseline levels at all follow-up points for all groups and urinalysis data did not differ between groups at follow-up. While CM produced robust evidence of efficacy during treatment application, CBT produced comparable longer-term outcomes. There was no evidence of an additive effect when the two treatments were combined. CONCLUSIONS: This study suggests that CM is an efficacious treatment for reducing stimulant use and is superior during treatment to a CBT approach. CM is useful in engaging substance abusers, retaining them in treatment and helping them achieve abstinence from stimulant use. CBT also reduces drug use from baseline levels and produces comparable outcomes on all measures at follow-up.     

Treatment Outcome of Alcoholics with and without Cocaine Disorders

The treatment outcome literature suggests that alcoholics with coexisting drug dependence have worse prognoses. We compared three groups of inpatients treated on the same hospital unit for disorders of alcohol only ( n = 51), cocaine only ( n = 27), or both disorders (dual group, n = 27). At follow-up, we contacted 105 (81%) of 129 patients at a mean of 13.4 ± 4.1 months after discharge. The three groups significantly and equivalently decreased their consumption of substances at follow-up, and they also had equivalent improvements in employment and in medical and psychiatric well-being. A nonsignificant trend existed for greater abstinence in the alcohol group (53%) than in the dual group (35%), and with regression analysis diagnostic group and stable residence predicted abstinence in the past 30 days. Elapsed time before using alcohol was equivalent for the two alcohol groups, and relapse to alcohol preceded relapse to cocaine by 1 month on average. In sum, outcomes were more similar than different for the three groups. Although specific treatments to enhance abstinence for cocaine users are indicated, clinicians should approach cocaine-using alcoholics with equal optimism for improvement as with other alcoholics.     

Six-Month Follow-Up of Short-Term Pharmacotherapy for Cocaine Dependence

This 6-month follow-up study of 43 of 72 patients who entered a 6-week randomized clinical trial of pharmacotherapy for cocaine dependence found that self-reported cocaine abstinence during the 6 months was significantly greater in patients treated with desipramine (44%) than in those treated with lithium (19%) or placebo (27%). The placebo group had more occurrences of depression (36% vs. 6%) and daily alcohol abuse (36% vs. 15%) than the medicated groups. The ability to abstain from cocaine use during the clinical trial was the strongest predictor of continued abstinence during the follow-up, which showed that 53% remained abstinent after 6 months.     

The efficacy of disulfiram for the treatment of alcohol use disorder

Background: Alcohol use disorders (AUD) involving hazardous, harmful, and addictive misuse of alcohol are widespread in most parts of the world. The aim of this study was to review the effect of disulfiram in the treatment of patients with AUD. The effect of disulfiram was evaluated according to the primary outcome of an intake of alcohol below 30 and 20 g/d for men and women, respectively, as well as secondary outcomes such as days until relapse, alcohol intake, and numbers of drinking days. Methods: A systematic review of the literature was conducted using MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL). Results: Eleven randomized controlled trials were included with a total of 1,527 patients. They compared disulfiram treatment with placebo, none or other abstinence‐supportive treatments. Overall, 6 studies reported of a significant better effect on abstinence for patients treated with disulfiram. Six of 9 studies measuring secondary outcomes reported that patients treated with disulfiram had significantly more days until relapse and fewer drinking days, respectively. The quality of the included studies was moderate. Heterogeneity was significant in most of the meta‐analyses, but valid results were found regarding the effect of disulfiram versus placebo over 12 months and unsupervised disulfiram versus other or no treatment. The vast majority of significant studies were of shorter duration, while only 3 studies of 12 months were significant regarding more days until relapse and/or reduction in drinking days. Conclusions: Supervised treatment with disulfiram has some effect on short‐term abstinence and days until relapse as well as number of drinking days when compared with placebo, none, or other treatments for patients with alcohol dependency or abuse. Long‐term effect on abstinence has not been evaluated yet. However, there is a need for more homogeneous and high‐quality studies in the future regarding the efficacy of disulfiram.     

Disulfiram treatment for cocaine dependence in methadone-maintained opioid addicts

Aims: Cocaine use by patients on methadone maintenance treatment is a widespread problem and is associated with a poorer prognosis. Recent studies have evaluated disulfiram as a treatment for individuals with comorbid alcohol and cocaine abuse. We evaluated the efficacy of disulfiram for cocaine dependence, both with and without co-morbid alcohol abuse, in a group of methadone-maintained opioid addicts. Design: Randomized double-blind, placebo-controlled trial. Setting: Urban methadone maintenance clinic. Participants: Sixty-seven cocaine-dependent, methadone-maintained, opioid-dependent subjects (52% female; 51% Caucasian). Intervention: Study medication, either disulfiram or placebo, was placed directly in the methadone to ensure compliance for 12 weeks. Measurements: Primary outcome measures included weekly assessments of the frequency and quantity of drug and alcohol use, weekly urine toxicology screens and breathalyzer readings. Findings: Disulfiram treated subjects decreased the quantity and frequency of cocaine use significantly more than those treated with placebo. Alcohol use was minimal for all subjects regardless of the medication. Conclusions: Disulfiram may be an effective pharmacotherapy for cocaine abuse among methadone-maintained opioid addicts, even in those individuals without co-morbid alcohol abuse. Disulfiram inhibits dopamine beta-hydroxylase resulting in an excess of dopamine and decreased synthesis of norepinephrine. Since cocaine is a potent catecholamine re-uptake inhibitor, disulfiram may blunt cocaine craving or alter the "high", resulting in a decreased desire to use cocaine.     

The impact of fatherhood on treatment response for men with co-occurring alcohol dependence and intimate partner violence

Objective: The role of fathers in the lives of children has gained increasing attention over the last several decades, however, studies that specifically examine the parenting role among men who are alcohol dependent and have co-occurring intimate partner violence (IPV) have been limited. This brief report is intended to highlight the need to develop and focus interventions for men with co-occurring substance abuse and IPV with an emphasis on their roles as fathers. Method: Sixty-nine men who participated in a randomized comparison study of a coordinated substance abuse and domestic violence treatment program (SADV) and Twelve Step Facilitation (TSF) provided information about whether they were fathers. Analysis of covariance was used to assess the impact of fatherhood on the outcomes of intimate partner violence and alcohol use during the 12 weeks of treatment. Results: There was a significant interaction between type of treatment (SADV vs. TSF) and fatherhood. SADV resulted in significantly less IPV and use of alcohol over the 12 weeks of treatment than TSF for men without children. There were no significant differences between SADV and TSF for men who were fathers. Conclusion and Scientific Significance: Results indicate a need to further explore the role of fatherhood for men with co-occurring substance abuse and IPV and development of specialized treatments that may improve treatment outcomes for fathers.     

Treatment of Alcohol Use Disorder in Patients with Alcoholic Liver Disease

Alcohol is a leading cause of liver disease worldwide. Although alcohol abstinence is the crucial therapeutic goal for patients with alcoholic liver disease, these patients have less access to psychosocial, behavioral, and/or pharmacologic treatments for alcohol use disorder. Psychosocial and behavioral therapies include 12-step facilitation, brief interventions, cognitive behavioral therapy, and motivational enhancement therapy. In addition to medications approved by the US Food and Drug Administration for alcohol use disorder (disulfiram, naltrexone, and acamprosate), recent efforts to identify potential new treatments have yielded promising candidate pharmacotherapies. Finally, more efforts are needed to integrate treatments across disciplines toward patient-centered approaches in the management of patients with alcohol use disorder and alcoholic liver disease.     

Coping skills training and contingency management treatments for marijuana dependence: exploring mechanisms of behavior change

AIMS: Achieving abstinence in the treatment of marijuana dependence has been difficult. To date the most successful treatments have included combinations of motivation enhancement treatment (MET) plus cognitive-behavioral coping skills training (CBT) and/or contingency management (ContM) approaches. Although these treatment approaches are theoretically based, their mechanisms of action have not been explored fully. The purpose of the present study was to explore mechanisms of behavior change from a marijuana treatment trial in which CBT and ContM were evaluated separately and in combination. DESIGN: A dismantling design was used in the context of a randomized clinical trial. SETTING: The setting was an out-patient treatment research facility located in a university medical center. PARTICIPANTS: Participants were 240 adult marijuana smokers, meeting criteria for cannabis dependence. INTERVENTIONS: Participants were assigned to one of four 9-week treatment conditions: a case management control condition, MET/CBT coping skills training, ContM and MET/CBT + ContM. MEASUREMENTS: Outcome measures were total 90-day abstinence, recorded every 90 days for 12 months post-treatment. FINDINGS: Regardless of treatment condition, abstinence in near-term follow-ups was predicted most clearly by abstinence during treatment, but long-term abstinence was predicted by use of coping skills and especially by post-treatment self-efficacy for abstinence. CONCLUSIONS: It was concluded that the most efficacious treatments for marijuana dependence are likely to be those that increase self-efficacy.     

Quality versus quantity: acquisition of coping skills following computerized cognitive–behavioral therapy for substance use disorders

Aims To evaluate the changes over time in quality and quantity of coping skills acquired following cognitive behavioral therapy (CBT), and examine potential mediating effects on substance use outcomes. Design A randomized controlled trial (RCT) evaluating the effectiveness of a computerized version of CBT (CBT4CBT) as an adjunct to standard out‐patient treatment over an 8‐week period. Setting Data were collected from individuals seeking treatment for substance dependence in an out‐patient community setting. Participants Fifty‐two substance abusing individuals (50% African American), with an average age of 42 years, and a majority reporting cocaine as their primary drug of choice. Measurements Participants' responses to behavioral role‐plays of situations associated with high risk for drug and alcohol use were audio‐taped and rated independently to assess their coping responses. Findings There were statistically significant increases in mean ratings of the quality of participants' coping responses for those assigned to CBT4CBT compared to treatment as usual, and these differences remained significant 3 months after treatment completion. Moreover, quality of coping responses mediated the effect of treatment on participants' duration of abstinence during the follow‐up period. Conclusions These findings suggest that assignment to the computerized CBT program improved participants' coping skills, as measured by independent ratings of a role‐playing task. It is also the first study to test and support quality of coping skills acquired as a mediator of the effect of CBT for substance use.     

Cost-effectiveness of a voucher-based intervention for smoking cessation

ABSTRACT

Background: Contingency management (CM) has been shown to be effective in reducing smoking consumption, but has traditionally been criticized for its costs. Objectives: This study assessed the cost-effectiveness of using a voucher-based CM protocol added to a cognitive behavioral treatment (CBT) for smoking cessation among treatment-seeking patients from the general population. Methods: A total of 92 patients were randomly assigned to CBT or CBT plus CM for abstinence. Incremental cost-effectiveness ratios (ICERs) were calculated by dividing the increase in costs by the increase in effects (continuous abstinence, longest duration of abstinence at 6-month follow-up and cotinine results during the treatment). An acceptability curve illustrated the statistical uncertainty surrounding the cost-effectiveness estimate. We also determined the optimum cost per participant for predicting the smoking status at 6-month follow-up. Results: The average cost per participant in the CBT condition was €138.73 (US$ 150.23) as opposed to €411.61 (US$ 445.73) in the CBT plus CM condition (p < 0.01). The incremental cost of using voucher-based CM to increase the number of participants that maintained abstinence at 6-month follow-up by one extra participant was €68.22 (US$ 73.88), and to lengthen the longest duration of abstinence by 1 week was €53.92 (US$ 58.39). The incremental cost to obtain an extra cotinine-negative result was €181.90 (US$ 196.98). Conclusion: Compared with CBT alone, the voucher-based protocol required additional costs but achieved significantly better outcomes. These results will allow stakeholders to make policy decisions about CM implementation for smoking cessation in the broader community.     

Effects of varying the monetary value of voucher-based incentives on abstinence achieved during and following treatment among cocaine-dependent outpatients

AIMS: This study examined whether increasing the amount of abstinence achieved during outpatient treatment for cocaine dependence is an effective method for increasing longer-term cocaine abstinence. DESIGN: A two-condition, parallel groups, randomized controlled trial was conducted. SETTING: The trial was conducted in a university-based research clinic. PARTICIPANTS: A total of 100 cocaine-dependent outpatients participated in the trial. INTERVENTION: Participants were assigned randomly to receive treatment based on the community reinforcement approach (CRA) plus voucher-based incentives set at a relatively high monetary value (maximal value = $1995/12 weeks) or CRA with vouchers set at a relatively low monetary value (maximal value = $499/12 weeks). Vouchers were earned contingent on cocaine-negative urinalysis results during the initial 12 weeks of the 24-week outpatient treatment. MEASUREMENTS: Outcomes were evaluated using urine-toxicology testing, questionnaires and other self-report instruments. FINDINGS: Increasing voucher value increased the duration of continuous cocaine abstinence achieved during the 24-week treatment period. Point-prevalence cocaine abstinence assessed every 3 months throughout an 18-month follow-up period was greater in the high- than low-value voucher conditions. The duration of abstinence achieved during treatment predicted abstinence during follow-up, although that relationship weakened over time. CONCLUSIONS: Increasing the value of abstinence-contingent incentives during the initial weeks of treatment appears to represent an effective method for increasing during-treatment and longer-term cocaine abstinence, but the positive association of during-treatment abstinence with longer-term outcome dissipates with time.     

Comparison of Cyanamide and Disulfiram in Effects on Liver Function

Background: Cyanamide, an aversive drug widely used in Japan, develops ground-glass inclusion bodies in the hepatocytes at high incidences, which may be associated with portal inflammation and fibrosis. When cyanamide-treated alcoholics relapse drinking, the combined effect of cyanamide and alcohol produce more severe portal inflammation along with the emergence of ground-glass inclusions. Disulfiram also causes hepatitis, but there have been no comparative studies of effects of cyanamide and disulfiram on liver function. Methods: We reviewed the laboratory data of 408 alcoholics admitted for a 3 month course of alcohol detoxification and rehabilitation. Patients tested negative for hepatitis virus markers and were diagnosed as not having cirrhosis. Among the subjects, 222 patients received cyanamide treatment (a daily dose of 70 mg) without a history of disulfiram treatment, and 186 received disulfiram (a daily dose of 200 mg) without a history of cyanamide treatment. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels obtained at 0, 4, 8, and 12 weeks of administration of each aversive drug were compared between the two alcoholic groups. Results: Elevation of serum transaminases (AST, > ALT) probably due to alcoholic liver disease quickly fell after abstinence. In patients who took cyanamide, the ALT levels were significantly higher at 4 and 12 weeks than in those who took disulfiram. Reelevations of ALT after alcohol detoxification were more frequently observed in those who took cyanamide than in those who took disulfiram (19.4% vs. 5.9%, p < 0.001). The reelevations of ALT were slight to moderate, being more than 3-fold in three (1.4%) patients who took cyanamide and four (2.2%) who took disulfiram. The reelevations occurred more frequently in those with a history of cyanamide treatment before the present treatment than in those who took cyanamide for the first time (31.1% vs. 16.4%, p < 0.05). Conclusions: Cyanamide, compared with disulfiram, was more frequently associated with elevations of ALT that persisted after abstinence.     

A Case Study of Mediators of Treatment Effectiveness

Background:  Recent research has observed that the use of confrontation in psychosocial treatment for alcohol abuse or dependence has a negative effect on posttreatment alcohol use among patients at average or above average levels of trait anger. It is not known what mediates that negative effect. The current study examines the role of session attendance as a mediator of the effect of confrontation on patients' subsequent alcohol use. In doing so, the study demonstrates the process of testing for mediation as well as planning analyses to meet additional conditions that can lend support to a causal mechanism of change.
Methods:  Multiple regression analyses were used to test for session attendance as a mediator among 107 individuals with alcohol abuse or dependence who received either cognitive behavioral therapy (CBT) ( n  =   39), motivational enhancement therapy (MET) ( n  =   34), or twelve-step facilitation therapy (TSF) ( n  =   34). Emphasis was placed on achieving the desired temporal sequence of the therapy intervention, the mediator, and the outcome variable.
Results:  The data supported the role of session attendance as a partial mediator of the effect of confrontation on future alcohol use among patients who received CBT, but not among patients who received MET or TSF. In CBT, other potential mediators (e.g., therapeutic alliance and in-session resistance) were not supported and did not change the support for session attendance in the model. Beyond mediation, some but not all criteria for a causal mechanism of change were also met.
Conclusions:  This study suggests that in CBT the negative impact of confrontation early in treatment is partially explained by a reduction in the number of sessions patients attended. Different processes appear to be occurring in MET and TSF. By carefully constructing analytic models, results can speak both to issues of mediation and to causal mechanisms of change.