James F. Maddux

Obtaining follow-up interviews for treatment evaluation☆

Studies of the outcomes of substance abuse treatment are often handicapped because of subjects lost to follow-up. While follow-up data may be obtained from several sources, the follow-up interview often serves as the principal source of data. Difficulties are regularly encountered in locating and interviewing subjects not in treatment. From review of the literature on follow-up methodology and our own experience, we identified 10 procedures for effective follow-up. Application of these procedures is illustrated in a follow-up study of illicit opioid users treated in a methadone maintenance program. Follow-up interviews were obtained with 98% of the subjects. We recommend use of the 10 procedures by follow-up researchers, and we also recommend review of several previous publications on follow-up methodology.

RELIABILITY AND VALIDITY OF INFORMATION FROM CHRONIC HEROIN USERS

Abstract Data on 12 life history variables obtained by interviews with 34 chronic heroin users at the time of admission to a treatment program were compared with data on the same variables obtained by later research interviews with the same subjects, and from other sources. The principal findings included: 1. (1) High percentages, 71 per cent or higher, of exact or approximate agreement between the two sources of information were found on nine of the 12 variables studied. This finding is consistent with reports of most previous studies by other investigators. 2. (2) With the exception of two variables, remarkably close agreement between the two sources was found in the estimates of central tendency and variability on the variables measured by interval scales. 3. (3) Noteworthy systematic discrepancy between the two sources was found on two variables: number of treatment interactions and number of arrests. The subjects underreported frequency of treatment and of arrest. 4. (4) Conditions which seemed to affect reliability of information included: refinement of measurement, misunderstanding of terms, elapsed time, repeated use, consequences of disclosure, the psychological defense of denial, and features of the interview 5. (5) Although the results of this study and of most previous studies show that chronic heroin users offen give reliable and valid life history information, uncritical acceptance seems as unwise as rejection of their statements.

Methadone Maintenance and Recovery from Opioid Dependence

While maintained on methadone, heroin users reduce their heroin use and related criminal activity and increase their legitimate employment. These benefits are obtained at the cost of continued opioid dependence. Furthermore, as a consequence of neural adaptation and conditioning, methadone maintenance may impede eventual recovery from opioid dependence. The authors attempt to assess such a possible effect by comparing long-term outcomes after methadone maintenance with those after drug-free treatment. In five long-term follow-up studies of methadone maintenance, the percentages found voluntarily abstinent ranged from 9 to 21. In six long-term follow-up studies of drug-free treatment, the percentages found voluntarily abstinent ranged from 10 to 19. These rates seem remarkably similar. They do not suggest that methadone maintenance impedes eventual recovery from opioid dependence, but they do not clearly exclude such an effect.

Ten-Year Follow-up after Admission to Methadone Maintenance

To assess the long-term effects of methadone maintenance, we compared the 10-year outcomes of 95 chronic opioid users who spent at least one cumulative year on methadone with those of 77 chronic opioid users who spent less than one cumulative year on methadone. All subjects were men and 90% were Mexican-American. The two groups were similar on 12 of 15 background variables. During the 10-year period, the methadone group had a cumulative mean of 54 months on methadone, while the comparison group had a cumulative mean of only 2 months on methadone. On social performance, as measured by months employed and months institutionalized, the methadone group did significantly better than did the comparison group. On months of voluntary abstinence, however, the comparison group did significantly better than did the methadone group. The mean of the comparison group, 36 months, was three times greater than that, 12 months, of the methadone group. At the end of the 10-year period, 26% of the comparison group but only 7% of the methadone group had been in continuous voluntary abstinence for 3 years or longer. Methadone maintenance for 1 year or longer was inversely related to abstinence during and at the end of the 10 years. This finding seems consistent with the hypothesis that methadone maintenance for 1 year or longer impedes eventual recovery from opioid dependence. For many patients, however, the benefits of prolonged maintenance could outweigh the possible cost of diminished likelihood of eventual recovery.

Religious Programs and Careers of Chronic Heroin Users

Religion is often overlooked as a factor in recovery from chronic opioid dependence. Research on the effectiveness of religious programs is scanty, but three reports in the literature suggest that programs of the Pentecostal type may be particularly effective among Hispanic drug users. In this paper we review the literature and report our own observations of religious program participation among 248 San Antonio addicts, 87% of whom are Hispanic (Mexican-American). In a 12-year period, 11% of the 248 entered religious programs. Although there were only 33 admissions, the percent followed by a year or more of abstinence (44%) markedly exceeded that following conventional treatment or correctional interventions. We conclude that the ability of religious programs to attract large numbers of clients is limited, but that major changes in attitudes and life-style occur among some participants. Successful participation seems to depend upon a special motivational state at admission. Religious programs may be conceived as sociotherapy, and are similar to traditional therapeutic communities and other self-help programs in many ways. We suggest some psychodynamic and sociocultural mechanisms which may explain how religion promotes recovery from chronic drug dependence among Hispanic heroin users.

Clinical Experience with Civil Commitment

Unstable motivation has represented a major problem in the treatment of opioid dependence. Early followup studies at the two Public Health Service Hospitals found that legally coerced treatment, especially when combined with compulsory posthospital care, led to better outcomes than did voluntary treatment. During the years 1967–1973, over 10,000 patients were admitted to the two hospitals under the NARA for evaluation of their suitability for treatment under civil commitment. Over one-third were found not suitable. Followup studies suggested that the outcomes of committed patients were somewhat better than those of voluntary patients. While civil commitment may bring some opioid users into treatment who would not voluntarily enter, it cannot overcome deficits in services, and it cannot insure that patients will participate in treatment.

Outpatient methadone withdrawal for heroin dependence.

The outcome of outpatient methadone withdrawal reported in 20 published studies during the 1970s varied widely: none to 62% of the patients completed withdrawal, none to 35% became abstinent at termination of withdrawal, and none to 38% were abstinent at follow-up. Although somewhat ambiguous, the results indicated that outpatient withdrawal did not lead to prolonged abstinence in most heroin users. In two studies in San Antonio we attempted to compare opioid use and other behavior during 1 year before and 1 year after outpatient withdrawal. In the first study the before and after comparison of opioid use was unsatisfactory because of follow-up attrition. The frequency of arrest, based on police records and not affected by the follow-up attrition, changed only slightly. In the second study the follow-up attrition was small (8%), and satisfactory comparison could be made. Months abstinent did not increase, but months maintained on methadone increased significantly. The follow-up results did not differ notably from those in inpatient withdrawal. Outpatient withdrawal limited to 21 days has the disadvantage that many persons are prematurely withdrawn and consequently resume heroin use.

Compulsory supervision and methadone maintenance

Treatment outcomes of 296 subjects admitted to methadone maintenance while on probation or parole are compared to those of 314 subjects admitted without such compulsory supervision. Equivalent treatment services were offered to both groups. The pretreatment differences between groups were small except for time incarcerated. All subjects were followed for one year. The compulsory supervision group had worse outcomes with respect to retention, productive activity, and incarceration. The differences were small except for incarceration. The mean number of months incarcerated was 2.1 for the compulsory supervision group and 0.7 for the voluntary group. Of subjects discharged from treatment, a higher percentage of the compulsory supervision group was discharged because of incarceration, but a higher percentage of the voluntary group was discharged for noncompliance with program requirements. The findings do not support a policy of exclusion of opioid users from methadone maintenance because they are on probation or parole.

Methadone Dose and Urine Morphine

When methadone maintenance was introduced in 1965, daily doses of approximately 100 mg were advocated and used; later, doses under 50 mg became common; recently, doses between 50 and 100 mg have been recommended. In a historical study and a cross-section study in one program the authors found no relationship between methadone dose and urine morphine. Patients on methadone doses under 50 mg had nearly the same percentage of urine tests positive for morphine as did those on doses of 50 mg and more. Gender, ethnic background, and age were also unrelated to urine morphine. Time on methadone was inversely related to urine morphine. Patients maintained on methadone for 3 years or longer showed a marked decrease in urine tests positive for morphine. Increased urine morphine during one decade was associated with program and community changes that could have prompted increased heroin use. These findings suggest that variables other than methadone dose affect heroin use.

Rapid Admission and Retention on Methadone

An open clinical trial was conducted to compare the effects of rapid (1-day) admission with slow (14-day) admission to methadone maintenance on pretreatment attrition, retention during treatment, and other outcomes. One hundred eighty-six illicit opioid users eligible for methadone maintenance were randomly assigned to rapid admission or slow admission, with 93 subjects assigned to each group. The random assignment produced two groups that were similar on 22 personal variables. All subjects admitted to treatment were followed for 1 year. Follow-up interviews were obtained with 155 (98%) of the 158 subjects admitted to treatment. During the period from initial contact to medication, only 4% of the rapid admission subjects but 26% of the slow admission subjects dropped out. The risk of dropout during slow admission was 6 times that during rapid admission. A higher percentage of rapid admission subjects, 43%, than of slow admission subjects, 39%, remained continuously in treatment for 1 year, but the difference was not significant. The two subgroups that remained in treatment for 1 year did about equally well on measures of illicit drug use and social performance. The findings indicate that pretreatment attrition can be markedly reduced by prompt medication, and the prompt medication does not adversely affect retention during treatment or other outcomes.