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Excessive alcohol consumption and drinking expectations among clients in methadone maintenance
Journal of Substance Abuse Treatment 21 (2001) 155 – 160
Regular article
Excessive alcohol consumption and drinking expectations among clients in methadone maintenance Jennifer Hillebrand, M.Sc., John Marsden, Ph.D.*, Emily Finch, MRCPsych, M.D., John Strang, FRCPsych, M.D. National Addiction Centre Institute of Psychiatry, Maudsley Hospital 4, Windsor Walk, London SE5 8AF, UK Received 23 October 2000; received in revised form 23 July 2001; accepted 23 July 2001
Abstract Excessive alcohol consumption and related problems are common among clients in methadone maintenance treatment (MMT), yet relatively little is known about the psychological and social determinants of alcohol-related attitudes and behaviors during treatment. This study reports on the prevalence of alcohol dependence, patterns of alcohol consumption and preliminary findings about clients’ beliefs that they will change their drinking behavior in the future. Data were gathered from personal interviews with 66 clients attending a MMT program in South London (some 80.5% of the eligible caseload). Forty-one percent of the overall sample met DSM-IV criteria for alcohol dependence in the past 12 months. Among clients who reported drinking in the past month (n = 50), 54% were classified as dependent, and these clients reported consuming an average of 23.5 UK standard units of absolute alcohol (188g/6.58 ounces) on a typical drinking day in the past month. Exploratory analyses suggested that expectations to change drinking behavior were predicted by subjective norms (social pressures), perceived functions of alcohol use, past drinking levels and current dose of methadone. Clinicians engaged in alcohol problems assessment and counseling during MMT could usefully examine these influences to strengthen treatment provision. D 2001 Elsevier Science Inc. All rights reserved. Keywords: Methadone maintenance treatment; Alcohol; Expectations; Functions
1. Introduction Clinical research conducted in the United States has shown that excessive alcohol use and alcohol-related problems are reported by at least half of clients receiving methadone maintenance treatment (MMT) (Maddux & Elliot, 1975; Joseph & Appel, 1985). Approximately one client in ten meets clinical criteria for alcohol dependence (Hunt, Strug, & Goldsmith, 1986; Chatham, Rowan-Szal, Joe, Brown, & Simpson, 1995) and these clients appear to stay in treatment longer and may be concurrently dependent on cocaine (Chatham, Rowan-Szal, Joe, & Simpson, 1997). In the United Kingdom, clinical studies have also shown that many MMT clients report excessive drinking patterns. Stastny & Potter (1991) found that 31% of a sample of
* Corresponding author. Tel.: +44-20-7848-0830; fax: +44-20-77018454. E-mail address: [email protected] (J. Marsden).
clients in methadone treatment scored seven or more on the Michigan Alcoholism Screening Test, while Best et al. (1998) reported that only 15% of those who had been drinking alcohol in the last month had consumed alcohol within the United Kingdom government’s recommended safe limits (21 units/week for women; 28/week for men [1 unit = 8g or 0.28 ounces ethanol]). Collectively, in this area these studies also indicate those clients in MMT who are alcohol dependent have a higher rate of mortality, a higher incidence of psychiatric symptoms, experience poorer social functioning, are more likely to continue to use illicit drugs and are at greater risk of drug overdose (Joseph & Appel, 1985; Roszell, Calsyn, & Chaney, 1986; Chatham et al., 1995; El-Bassel, Schilling, Turnbull, & Su 1993; Best, Gossop, Lehmann, Harris, & Strang, 1999). During and posttreatment changes in alcohol use by MMT clients have been examined by several outcome studies. For example, as part of the National Treatment Outcome Research Study in the United Kingdom, alcohol use was assessed prospectively for 313 clients who had been
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drinking before treatment and who were contacted at a oneyear follow-up. For these clients, the percentage of drinking days in the past 3 months reduced from 33.7% to 28.1% and the amount consumed on a typical drinking day reduced from 10.6 units to 7.5 units. However, the proportion of clients who continued to drink over the recommended weekly unit limits was unchanged at the follow-up (23%) as was the number of clients who were daily drinkers (10.7% at intake and 10.5% at follow-up) (Gossop, Marsden, Stewart, & Rolfe, 2000). In the United States, Lehman, Barrett, and Simpson (1990) followed up 298 ex-heroin users 12 years after entering MMT and found that approximately a quarter could be classified as heavy drinkers, and half reported they drank alcohol as a substitute for heroin. These results indicate that excessive drinking continues to be a problem among many current and former MMT clients, particularly those who were heavy drinkers at intake. There is also evidence in the United States that engaging and treating MMT clients with combined opioid, cocaine and alcohol problems is more challenging than working with clients with less opioid polydrug use (Rowan-Szal, Chatham, & Simpson, 2000). There has been little research conducted on the reasons, motivations and other individual and social factors that influence drinking behavior among the MMT client population. A greater understanding of these factors may be helpful in strengthening methadone services to tackle alcohol problems. In this article, we report the results of a modest cross-sectional study of alcohol consumption patterns, dependence, attitudes and expectations to use alcohol among clients receiving MMT at a treatment program in London. A focus of the study was the extent to which clients were committed to their current drinking behaviors and, conversely, the extent to which they expect to change these in the near future. The Theory of Reasoned Action (TRA) was used as an organizing framework for exploring the influences on drinking behavior (Ajzen & Fishbein, 1980). The TRA has been successfully used to predict social and health behaviors in a variety of fields. The theory postulates that the immediate determinant of changing alcohol use is behavioral intention (defined in this context as the degree to which a person has formulated conscious plans to do so) and that the strength of intention to drink is also mediated by the person’s attitude toward drinking and the extent to which there are perceived subjective norms or perceived social pressures.
2. Materials and methods 2.1. Participants Participants were recruited from one of our communitybased MMT programs in South London, which serves a local catchment area population. In the program, methadone is provided to clients via prescriptions dispensed by a community retail pharmacy for self-administration. This
remains the most common means of delivering MMT in the United Kingdom (Marsden, Gossop, Farrell, & Strang, 1998a). The staffing and capacity of the studied program is typical of an urban area MMT program in the United Kingdom. The sampling frame for the study was the current caseload of clients receiving MMT during the research recruitment period. Clients who were dependent on opioids, who were 18 or more years of age and who had been stabilized on methadone for at least a one month were eligible to participate in the study. The research ethics committee of the Maudsley Hospital and Institute of Psychiatry approved the study. 2.2. Measures and procedure Data were gathered during a 12-week period from June to August 1999. A brief researcher-administered interview of approximately 15 minutes was developed and administered in an interview room at the program. The interview contained the following measures: use of illicit (nonprescribed) substances in the past month, alcohol dependence criteria for the past year, drinking motivations, alcoholrelated beliefs, and a brief treatment history on alcoholrelated problems. Dependence was assessed using the criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; American Psychiatric Association, 1994). The criteria encompassed the following aspects: tolerance; withdrawal; drinking more or over a longer period than intended; persistent desire or unsuccessful efforts to control; devoting substantial amounts of time to drinking; reducing or giving up social, occupational or recreational activities; and continued drinking despite persistent or recurrent physical and psychological problems. A positive response to three or more of the above markers in the past year was taken as identifying alcohol dependence. Alcohol consumption was recorded as the number of drinking days in the past month and the typical amount consumed on a drinking day, based on brief assessment procedures developed by Marsden et al. (1998b). Client self-reports of the quantity of alcohol used were recorded verbatim and later converted into UK standardized units of ethanol (1 unit = one half pint of ordinary strength beer [3% abv], or 8g/0.28 ounces ethanol). Participants were asked if they had ever received any treatment for a primary alcohol problem and for those with a treatment history, the number of times of admission to short-term inpatient, therapeutic community, outpatient treatment and Alcoholics Anonymous (AA) contact was recorded. To explore clients’ personal motivations for drinking, we used a nine-item scale measuring perceived functions of use adapted from research conducted with polydrug users by Boys et al. (1999). The scale records the frequency that the client recalls drinking to fulfill the following personal and social functions based on a five-point Likert-type scale (‘‘never-always’’; coded 0 – 4): to counter negative mood; to relax; to get to sleep; to increase the effects of methadone
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or other drugs; to help ‘‘get going’’ [washed and dressed] in the morning; to stop feeling sick in the morning; to enjoy the company of friends; to calm down after using other drugs; to counter boredom; and to help to forget problems. Higher scores on the scale indicated the individual was more likely to perceive that his/her drinking was performed to fulfill specific functions. These alcohol use functions were measured over the last 12 months. Warshaw & Davis (1985) have distinguished between behavioral intention and behavioral expectation, with the latter defined as an individual’s estimation of the likelihood that he or she will perform some specified future behavior. Since intentions may not reliably account for behaviors in the case of partly or completely nonvolitional behaviors, we elected to examine clients’ expectations for behavior change (i.e., the extent to which change is envisaged and conscious plans may or may not have been made to do so). In order to explore beliefs about areas of likely change in alcohol use, and in the absence of a suitable existing measure for the purpose, we developed a short scale to assess this. Clients were asked to estimate the likelihood of changing six aspects of their drinking repertoire in the next six months: avoiding drinking in certain places; reducing the quantity of weekly drinking; avoiding drinking strong drinks; not drinking alone; avoiding drinking with certain people; and drinking less with certain friends. Responses were scored using a seven-point scale ranging from 1 (extremely unlikely) to 7 (extremely likely). A composite score was then computed by summing the item weights, with higher scores reflecting a greater expectation to change the measured aspects of drinking behavior. We also included several measures of alcohol-related beliefs as suggested by Ajzen & Fishbein (1980) when employing the TRA as a measurement framework. Studies of alcohol use among young people have shown that past behavior is a significant predictor of behavioral intention (Bentler & Speckart, 1979; O’Callaghan, Chant, Callan, & Baglioni, 1997) and we therefore incorporated past alcohol use in the present assessment of the TRA model. Attitudes toward consuming alcohol were measured by six, sevenpoint adjective scales (scored 1 to 7) with end-points of ‘‘good-bad’’; ‘‘beneficial-harmful’’; ‘‘rewarding-punishing’’; ‘‘relaxing-agitating’’; ‘‘desirable-undesirable’’; and ‘‘social-isolating.’’ Subjective norms (social pressure) were measured by asking the client to indicate their beliefs about the extent to which people who are important to them (partner, family, friends) think they should make the following seven changes in the next six months: stop drinking; reducing the amount drunk; avoid drinking in certain places; spending less money on alcohol; avoid strong drinks; drinking less with certain people and not drinking alone. In order to establish correspondence with the measurement of behavioral expectations, these subjective norms were measured using a seven-point semantic differential scale with ‘‘agreedisagree’’ as endpoints. A composite subjective norms score was then computed by summing the item weights.
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2.3. Analytical methods The internal reliability of scale items was assessed using Cronbach’s alpha coefficients. Differences between means were analyses using Student’s t-test and predictors of expectations to change drinking behavior were analyzed using standard multiple regression analysis with backwards elimination of covariates.
3. Results 3.1. Sample characteristics At initiation of recruitment to the study, there were 110 clients who had been in treatment for one month or more in the program. Of these, 97 attended the service during the recruitment period and were invited to participate. Sixteen (16.3%) refused (largely on the grounds that they had insufficient time available) and 15 (15.5%) did not fulfill the inclusion criteria. The final interview sample therefore comprised 66 clients (80.5% of the eligible, consenting caseload). Of the 66 recruited clients, 50 (75.8%) reported drinking on one or more occasions in the last 30 days prior to the interview and the following results pertain to this group. The personal characteristics of the sample were as follows: 74% male (n = 37); average age was 34.6 years (SD = 8.0); the mean duration of the current treatment episode was 28.5 months (SD = 31.9) and clients were prescribed an average dose of 49.06 mg of methadone per day (SD = 26.74). The average number of reported drinking days in the past month was 14.6 (SD = 12.1, range 1– 30), with 23.5 units (SD = 22.1; 188g/6.58 ounces) consumed on a typical day. Illicit heroin, stimulants and benzodiazepine use was reported by 62.1%, 47.0% and 31.8% respectively of these clients in the past month. Twenty-seven clients (54%; 40.9% of the total sample) met at least three DSM-IV criteria for alcohol dependence for the preceding 12 months. Regarding alcohol treatment, only one person among the alcohol dependent clients was currently receiving treatment for alcohol problems and only one person had previously received treatment primarily for alcohol problems in the sample. Past attendance at AA meetings were reported by a small minority (n = 6). No client reported current attendance at AA meetings. Minor differences were observed between alcohol dependent and nondependent clients. Alcohol dependent clients reported drinking more days in the last month alone at home (mean = 0.59, SD = 0.5) (t[48] = 2.04, p < 0.05) and drank more days in the last month with their friends at home (mean = 4.81, SD = 21.2) (t[48] = 2.56, p < 0.05). No statistical differences were found between these groups on dose of methadone, number of days they used heroin, stimulants and benzodiazepines in the last 30 days and length of treatment.
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3.2. Perceived functions for alcohol use Study participants were asked to indicate which of the set of nine different functions they had used alcohol to fulfill in the past 12 months. For clarity of presentation, responses were initially recoded by combining the ‘‘rarely/sometimes’’ and ‘‘often/always’’ categories. The prevalence of drinking to fulfill the individual functions is shown in Table 1. As can be seen, the most frequently cited functions of drinking were to relax, to alleviate boredom, to improve negative mood, to forget problems, and to help to get to sleep. However, approximately one-third of the clients reporting drinking with the intention of increasing the psychoactive effects of methadone or other drugs; and approximately onefifth of the clients reported drinking to help to feel calmer after using other drugs. When item weights were summed on the function scale, the score ranged from 0 to 34. The distribution of scores was reasonably normally distributed (mean score = 11.1, median = 11.0, SD = 8.4). The internal reliability for the nine-item scale was satisfactory (alpha = 0.88). 3.3. Expectations to change drinking behavior The proportion of the clients who indicated they considered it ‘‘likely, very likely or extremely likely’’ they would change aspects of their drinking repertoire, was as follows: avoid drinking strong drinks (38%); avoid drinking with certain people (34%); avoid drinking in certain places (34%); reduce the weekly amount of alcohol consumed (30%); drinking less with certain friends (30%); and not drinking alone (28%). When the individual item’s scores were summed, the total expectation scale score ranged from 7 (extremely unlikely) to 49 (extremely likely). The distribution of scores was reasonably normally distributed (mean = 22.2, median = 22.4, SD = 11.9. The internal reliability for the nine-item scale was satisfactory (alpha = 0.88). Following this, we then performed a multiple regression analysis with backwards elimination of covariates to examine the extent to which expectations to change drinking behavior (expectations total score) could be predicted by age, gender, subjective norms, methadone dose, the number of days of alcohol use in the last month, perceived functions for alcohol use (total score), and attitudes toward alcohol Table 1 Prevalence of drinking to fulfil specific functions (n = 50) Function
%
To To To To To To To To To
84 68 66 64 54 30 28 24 24
help to relax stop feeling bored make yourself feel better when low or depressed forget problems help to get to sleep increase the effects of methadone or any other drug help to ‘‘get going’’ in the morning stop feeling sick in the morning calm after using other drugs
consumption. While the cases to covariates ratio was 7:1, which exceeds a minimum to perform multiple regression analysis, given the small sample size this analysis should be seen as preliminary and exploratory. Four variables appeared to predict expectations to change drinking behavior. The strongest was subjective norm, which was positively related to expectations to change drinking behavior. The other variables in order of strength of effect were as follows: perceived functions of alcohol use; the number of days used alcohol in the last 30 days; and dose of methadone had significant regression coefficients. These variables were negatively related to the expectation measure. Overall, 51% of the variability in expectation to change aspects of alcohol consumption over the next 6 months was predicted by knowledge of scores of subjective norm, perceived function of alcohol use and dose of methadone.
4. Discussion The aim of the present study was to examine the prevalence of alcohol use and alcohol dependence among clients receiving MMT at a London clinic and explore their alcohol-related expectations. The levels of alcohol consumption were varied, but generally quite substantial, with 76% of the sample having consumed at least one alcoholic drink in the last 30 days and with current drinkers, 41% meeting DSM-IV alcohol dependence diagnostic criteria for the preceding 12 months. Different investigators have used different instruments and thresholds to assess alcohol use and abuse, and this has created difficulties in comparing results across studies. One study from the United States, using a criterion employing positives among five DSM-III-R equivalent items to diagnose alcohol dependence among clients in MMT, reported a cohort prevalence of 9.2% (Chatham et al., 1995). This percentage appears low compared to the rate found in the present investigation. However, Chatham et al. (1995) defined alcoholism by at least three positive responses to only five DSM-III-R items, which provides a conservative estimation. Although a more liberal criterion was used in the present study, it was clear that symptoms related to alcohol dependence were common. Our study also investigated the extent to which clients believed they would make changes to their drinking behavior during the next 6 months. Nearly 40% of the sample reported that, during this period they considered they would try to avoid consuming strong alcoholic beverages and around one-third reported they would try to avoid drinking with certain people, to avoid drinking in certain places, to reduce their weekly level of consumption and to avoid drinking alone. Using the framework of the TRA, we conducted an exploratory regression analysis to model variations in their expectancy behaviors and were able to account for 51% in rating scale variability using a set of seven covariates. The strongest positive predictor of expectations was subjective norms, suggesting that the more that
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‘‘important others’’ think a client should change his/her drinking behavior over the next six months, the more clients expect to see themselves change these aspects. This finding is surprising since most previous research has reported that intentions tend to be more under attitudinal control than under normative influence (O’Callaghan et al., 1997; Schlegel, Crawford, & Sanborn, 1977). In fact, attitudes toward alcohol did not appear to predict change expectancies to any great extent. Although the finding is preliminary due to the small sample size in this study, it provides some suggestions on how problematic alcohol use might be reduced among methadone maintenance clients. One possible explanation for the importance of subjective norm stems from the hypotheses that opioid dependent clients are apt to be more under normative control due to their previous history of drug and drug associated problems. Because of these problems they represent a vulnerable group with possible low self-esteem and this could be a reason they are more prone to normative influences. Therefore, MMT program staff should be alert to the insights that may be derived from exploration of their clients’ self-concepts and possible implications with regard to concurrent drug consumption and overall social and emotional functioning. The second strongest predictor of future expectations was perceived functions of alcohol use. The more frequently clients perceived their alcohol use as serving specific functions, the less likely they were to expect to change their alcohol use pattern. We suggest that this preliminary finding, if replicated in further studies, has important clinical implications for tackling alcohol problems in MMT. Following an assessment of a specific alcohol use function reported by a client, help should be provided to develop alternative ways of fulfilling these functions. In the present study, drinking to relax, to alleviate boredom and to improve negative mood were all commonly cited. The clinician who elicits the active presence of these functions in a particular client should then plan the incorporation of relevant additional psychological and social support to supplement the standard MMT program. This might be of particular importance for those clients who are dependent on alcohol, whom we found drank more often alone or with friends at home. Ways of engaging clients in wider activities to fulfill these functions should be incorporated into the overall medical, psychological and social treatment plan for their care. Other functions that were less common among this sample might also be of importance for individual clients and need to be explored by the clinician. In particular, the use of alcohol to increase the effects of methadone should be closely examined in routine clinical practice. Further work is needed to examine this behavior and to assess the levels of alcohol consumed and methadone dose taken. Since combined CNS depressant use has been linked to cases of opioid overdose (Strang et al., 1999), clients who drink heavily while in MMT treatment may be at risk, and drinking to increase the effects of methadone should be
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assessed and discussed as part of ongoing care planning and review. We also suggest the clinician should assess the particular client’s expectations to change alcohol use behaviors in the near future. This would provide the opportunity to explore anticipated problems the client might have to change certain drinking behaviors. Another implication for treatment concerns the influence of ‘‘important others’’ who are currently often neglected in the treatment process. Additional variance in expectations to change aspects of alcohol use was accounted for by negative relationships with past alcohol use and current daily dose of methadone. This suggests that the more days a client consumes alcohol in the last 30 days, the less he or she expects to change alcohol use behavior in the short term. A higher dose of methadone was also associated with reduced likelihood of changing alcohol use over the next 6 months. It may be that clients with relatively higher doses of methadone are more attached to drinking behavior, and are less likely to wish to alter their drinking pattern. This interpretation is speculative and the relationship between dose of methadone and motivation for alcohol use should be clarified in future research. Several limitations to the study need to be borne in mind. First, the use of retrospective self-report data on alcohol consumption restricts the validity of the results and we were not able to conduct an independent validation. Second, the sample was small in size and should be repeated with a more substantial group and in other localities. Third, no information was obtained of the extent to which alcohol issues are already being adequately addressed within the methadone treatment program itself. Future research in this area should consider these limitations and explore who could be the key persons to change each individual client’s expectations. Overall, the present study confirms previous research that has documented the substantial extent of, and lack of treatment for alcohol related problems that occur among patients in methadone maintenance (El Bassel et al., 1993). Among our sample, only one client was currently receiving treatment for their alcohol dependence. A stronger focus on the treatment of polydrug use in methadone maintenance services and a close cooperation with other services and AA groups could be important first steps to combat this insufficiency. The results from this study also point to the need for methadone prescribing programs to make a concerted effort to assess and respond to heavy drinking and alcoholrelated problems among their clients.
Acknowledgments The authors express their thanks to the staff and clients of the South London Methadone program for their support and assistance during the study. Grant support was provided by the National Addiction Centre. The study was substantially undertaken as the research project for the M.Sc. in Clinical
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and Public Health Aspects of the Addictions (University of London) at the National Addiction Centre by the lead author (J. Hillebrand).
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Regular article
Excessive alcohol consumption and drinking expectations among clients in methadone maintenance Jennifer Hillebrand, M.Sc., John Marsden, Ph.D.*, Emily Finch, MRCPsych, M.D., John Strang, FRCPsych, M.D. National Addiction Centre Institute of Psychiatry, Maudsley Hospital 4, Windsor Walk, London SE5 8AF, UK Received 23 October 2000; received in revised form 23 July 2001; accepted 23 July 2001
Abstract Excessive alcohol consumption and related problems are common among clients in methadone maintenance treatment (MMT), yet relatively little is known about the psychological and social determinants of alcohol-related attitudes and behaviors during treatment. This study reports on the prevalence of alcohol dependence, patterns of alcohol consumption and preliminary findings about clients’ beliefs that they will change their drinking behavior in the future. Data were gathered from personal interviews with 66 clients attending a MMT program in South London (some 80.5% of the eligible caseload). Forty-one percent of the overall sample met DSM-IV criteria for alcohol dependence in the past 12 months. Among clients who reported drinking in the past month (n = 50), 54% were classified as dependent, and these clients reported consuming an average of 23.5 UK standard units of absolute alcohol (188g/6.58 ounces) on a typical drinking day in the past month. Exploratory analyses suggested that expectations to change drinking behavior were predicted by subjective norms (social pressures), perceived functions of alcohol use, past drinking levels and current dose of methadone. Clinicians engaged in alcohol problems assessment and counseling during MMT could usefully examine these influences to strengthen treatment provision. D 2001 Elsevier Science Inc. All rights reserved. Keywords: Methadone maintenance treatment; Alcohol; Expectations; Functions
1. Introduction Clinical research conducted in the United States has shown that excessive alcohol use and alcohol-related problems are reported by at least half of clients receiving methadone maintenance treatment (MMT) (Maddux & Elliot, 1975; Joseph & Appel, 1985). Approximately one client in ten meets clinical criteria for alcohol dependence (Hunt, Strug, & Goldsmith, 1986; Chatham, Rowan-Szal, Joe, Brown, & Simpson, 1995) and these clients appear to stay in treatment longer and may be concurrently dependent on cocaine (Chatham, Rowan-Szal, Joe, & Simpson, 1997). In the United Kingdom, clinical studies have also shown that many MMT clients report excessive drinking patterns. Stastny & Potter (1991) found that 31% of a sample of
* Corresponding author. Tel.: +44-20-7848-0830; fax: +44-20-77018454. E-mail address: [email protected] (J. Marsden).
clients in methadone treatment scored seven or more on the Michigan Alcoholism Screening Test, while Best et al. (1998) reported that only 15% of those who had been drinking alcohol in the last month had consumed alcohol within the United Kingdom government’s recommended safe limits (21 units/week for women; 28/week for men [1 unit = 8g or 0.28 ounces ethanol]). Collectively, in this area these studies also indicate those clients in MMT who are alcohol dependent have a higher rate of mortality, a higher incidence of psychiatric symptoms, experience poorer social functioning, are more likely to continue to use illicit drugs and are at greater risk of drug overdose (Joseph & Appel, 1985; Roszell, Calsyn, & Chaney, 1986; Chatham et al., 1995; El-Bassel, Schilling, Turnbull, & Su 1993; Best, Gossop, Lehmann, Harris, & Strang, 1999). During and posttreatment changes in alcohol use by MMT clients have been examined by several outcome studies. For example, as part of the National Treatment Outcome Research Study in the United Kingdom, alcohol use was assessed prospectively for 313 clients who had been
0740-5472/01/$ – see front matter D 2001 Elsevier Science Inc. All rights reserved. PII: S 0 7 4 0 - 5 4 7 2 ( 0 1 ) 0 0 1 9 8 - 2
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drinking before treatment and who were contacted at a oneyear follow-up. For these clients, the percentage of drinking days in the past 3 months reduced from 33.7% to 28.1% and the amount consumed on a typical drinking day reduced from 10.6 units to 7.5 units. However, the proportion of clients who continued to drink over the recommended weekly unit limits was unchanged at the follow-up (23%) as was the number of clients who were daily drinkers (10.7% at intake and 10.5% at follow-up) (Gossop, Marsden, Stewart, & Rolfe, 2000). In the United States, Lehman, Barrett, and Simpson (1990) followed up 298 ex-heroin users 12 years after entering MMT and found that approximately a quarter could be classified as heavy drinkers, and half reported they drank alcohol as a substitute for heroin. These results indicate that excessive drinking continues to be a problem among many current and former MMT clients, particularly those who were heavy drinkers at intake. There is also evidence in the United States that engaging and treating MMT clients with combined opioid, cocaine and alcohol problems is more challenging than working with clients with less opioid polydrug use (Rowan-Szal, Chatham, & Simpson, 2000). There has been little research conducted on the reasons, motivations and other individual and social factors that influence drinking behavior among the MMT client population. A greater understanding of these factors may be helpful in strengthening methadone services to tackle alcohol problems. In this article, we report the results of a modest cross-sectional study of alcohol consumption patterns, dependence, attitudes and expectations to use alcohol among clients receiving MMT at a treatment program in London. A focus of the study was the extent to which clients were committed to their current drinking behaviors and, conversely, the extent to which they expect to change these in the near future. The Theory of Reasoned Action (TRA) was used as an organizing framework for exploring the influences on drinking behavior (Ajzen & Fishbein, 1980). The TRA has been successfully used to predict social and health behaviors in a variety of fields. The theory postulates that the immediate determinant of changing alcohol use is behavioral intention (defined in this context as the degree to which a person has formulated conscious plans to do so) and that the strength of intention to drink is also mediated by the person’s attitude toward drinking and the extent to which there are perceived subjective norms or perceived social pressures.
2. Materials and methods 2.1. Participants Participants were recruited from one of our communitybased MMT programs in South London, which serves a local catchment area population. In the program, methadone is provided to clients via prescriptions dispensed by a community retail pharmacy for self-administration. This
remains the most common means of delivering MMT in the United Kingdom (Marsden, Gossop, Farrell, & Strang, 1998a). The staffing and capacity of the studied program is typical of an urban area MMT program in the United Kingdom. The sampling frame for the study was the current caseload of clients receiving MMT during the research recruitment period. Clients who were dependent on opioids, who were 18 or more years of age and who had been stabilized on methadone for at least a one month were eligible to participate in the study. The research ethics committee of the Maudsley Hospital and Institute of Psychiatry approved the study. 2.2. Measures and procedure Data were gathered during a 12-week period from June to August 1999. A brief researcher-administered interview of approximately 15 minutes was developed and administered in an interview room at the program. The interview contained the following measures: use of illicit (nonprescribed) substances in the past month, alcohol dependence criteria for the past year, drinking motivations, alcoholrelated beliefs, and a brief treatment history on alcoholrelated problems. Dependence was assessed using the criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; American Psychiatric Association, 1994). The criteria encompassed the following aspects: tolerance; withdrawal; drinking more or over a longer period than intended; persistent desire or unsuccessful efforts to control; devoting substantial amounts of time to drinking; reducing or giving up social, occupational or recreational activities; and continued drinking despite persistent or recurrent physical and psychological problems. A positive response to three or more of the above markers in the past year was taken as identifying alcohol dependence. Alcohol consumption was recorded as the number of drinking days in the past month and the typical amount consumed on a drinking day, based on brief assessment procedures developed by Marsden et al. (1998b). Client self-reports of the quantity of alcohol used were recorded verbatim and later converted into UK standardized units of ethanol (1 unit = one half pint of ordinary strength beer [3% abv], or 8g/0.28 ounces ethanol). Participants were asked if they had ever received any treatment for a primary alcohol problem and for those with a treatment history, the number of times of admission to short-term inpatient, therapeutic community, outpatient treatment and Alcoholics Anonymous (AA) contact was recorded. To explore clients’ personal motivations for drinking, we used a nine-item scale measuring perceived functions of use adapted from research conducted with polydrug users by Boys et al. (1999). The scale records the frequency that the client recalls drinking to fulfill the following personal and social functions based on a five-point Likert-type scale (‘‘never-always’’; coded 0 – 4): to counter negative mood; to relax; to get to sleep; to increase the effects of methadone
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or other drugs; to help ‘‘get going’’ [washed and dressed] in the morning; to stop feeling sick in the morning; to enjoy the company of friends; to calm down after using other drugs; to counter boredom; and to help to forget problems. Higher scores on the scale indicated the individual was more likely to perceive that his/her drinking was performed to fulfill specific functions. These alcohol use functions were measured over the last 12 months. Warshaw & Davis (1985) have distinguished between behavioral intention and behavioral expectation, with the latter defined as an individual’s estimation of the likelihood that he or she will perform some specified future behavior. Since intentions may not reliably account for behaviors in the case of partly or completely nonvolitional behaviors, we elected to examine clients’ expectations for behavior change (i.e., the extent to which change is envisaged and conscious plans may or may not have been made to do so). In order to explore beliefs about areas of likely change in alcohol use, and in the absence of a suitable existing measure for the purpose, we developed a short scale to assess this. Clients were asked to estimate the likelihood of changing six aspects of their drinking repertoire in the next six months: avoiding drinking in certain places; reducing the quantity of weekly drinking; avoiding drinking strong drinks; not drinking alone; avoiding drinking with certain people; and drinking less with certain friends. Responses were scored using a seven-point scale ranging from 1 (extremely unlikely) to 7 (extremely likely). A composite score was then computed by summing the item weights, with higher scores reflecting a greater expectation to change the measured aspects of drinking behavior. We also included several measures of alcohol-related beliefs as suggested by Ajzen & Fishbein (1980) when employing the TRA as a measurement framework. Studies of alcohol use among young people have shown that past behavior is a significant predictor of behavioral intention (Bentler & Speckart, 1979; O’Callaghan, Chant, Callan, & Baglioni, 1997) and we therefore incorporated past alcohol use in the present assessment of the TRA model. Attitudes toward consuming alcohol were measured by six, sevenpoint adjective scales (scored 1 to 7) with end-points of ‘‘good-bad’’; ‘‘beneficial-harmful’’; ‘‘rewarding-punishing’’; ‘‘relaxing-agitating’’; ‘‘desirable-undesirable’’; and ‘‘social-isolating.’’ Subjective norms (social pressure) were measured by asking the client to indicate their beliefs about the extent to which people who are important to them (partner, family, friends) think they should make the following seven changes in the next six months: stop drinking; reducing the amount drunk; avoid drinking in certain places; spending less money on alcohol; avoid strong drinks; drinking less with certain people and not drinking alone. In order to establish correspondence with the measurement of behavioral expectations, these subjective norms were measured using a seven-point semantic differential scale with ‘‘agreedisagree’’ as endpoints. A composite subjective norms score was then computed by summing the item weights.
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2.3. Analytical methods The internal reliability of scale items was assessed using Cronbach’s alpha coefficients. Differences between means were analyses using Student’s t-test and predictors of expectations to change drinking behavior were analyzed using standard multiple regression analysis with backwards elimination of covariates.
3. Results 3.1. Sample characteristics At initiation of recruitment to the study, there were 110 clients who had been in treatment for one month or more in the program. Of these, 97 attended the service during the recruitment period and were invited to participate. Sixteen (16.3%) refused (largely on the grounds that they had insufficient time available) and 15 (15.5%) did not fulfill the inclusion criteria. The final interview sample therefore comprised 66 clients (80.5% of the eligible, consenting caseload). Of the 66 recruited clients, 50 (75.8%) reported drinking on one or more occasions in the last 30 days prior to the interview and the following results pertain to this group. The personal characteristics of the sample were as follows: 74% male (n = 37); average age was 34.6 years (SD = 8.0); the mean duration of the current treatment episode was 28.5 months (SD = 31.9) and clients were prescribed an average dose of 49.06 mg of methadone per day (SD = 26.74). The average number of reported drinking days in the past month was 14.6 (SD = 12.1, range 1– 30), with 23.5 units (SD = 22.1; 188g/6.58 ounces) consumed on a typical day. Illicit heroin, stimulants and benzodiazepine use was reported by 62.1%, 47.0% and 31.8% respectively of these clients in the past month. Twenty-seven clients (54%; 40.9% of the total sample) met at least three DSM-IV criteria for alcohol dependence for the preceding 12 months. Regarding alcohol treatment, only one person among the alcohol dependent clients was currently receiving treatment for alcohol problems and only one person had previously received treatment primarily for alcohol problems in the sample. Past attendance at AA meetings were reported by a small minority (n = 6). No client reported current attendance at AA meetings. Minor differences were observed between alcohol dependent and nondependent clients. Alcohol dependent clients reported drinking more days in the last month alone at home (mean = 0.59, SD = 0.5) (t[48] = 2.04, p < 0.05) and drank more days in the last month with their friends at home (mean = 4.81, SD = 21.2) (t[48] = 2.56, p < 0.05). No statistical differences were found between these groups on dose of methadone, number of days they used heroin, stimulants and benzodiazepines in the last 30 days and length of treatment.
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3.2. Perceived functions for alcohol use Study participants were asked to indicate which of the set of nine different functions they had used alcohol to fulfill in the past 12 months. For clarity of presentation, responses were initially recoded by combining the ‘‘rarely/sometimes’’ and ‘‘often/always’’ categories. The prevalence of drinking to fulfill the individual functions is shown in Table 1. As can be seen, the most frequently cited functions of drinking were to relax, to alleviate boredom, to improve negative mood, to forget problems, and to help to get to sleep. However, approximately one-third of the clients reporting drinking with the intention of increasing the psychoactive effects of methadone or other drugs; and approximately onefifth of the clients reported drinking to help to feel calmer after using other drugs. When item weights were summed on the function scale, the score ranged from 0 to 34. The distribution of scores was reasonably normally distributed (mean score = 11.1, median = 11.0, SD = 8.4). The internal reliability for the nine-item scale was satisfactory (alpha = 0.88). 3.3. Expectations to change drinking behavior The proportion of the clients who indicated they considered it ‘‘likely, very likely or extremely likely’’ they would change aspects of their drinking repertoire, was as follows: avoid drinking strong drinks (38%); avoid drinking with certain people (34%); avoid drinking in certain places (34%); reduce the weekly amount of alcohol consumed (30%); drinking less with certain friends (30%); and not drinking alone (28%). When the individual item’s scores were summed, the total expectation scale score ranged from 7 (extremely unlikely) to 49 (extremely likely). The distribution of scores was reasonably normally distributed (mean = 22.2, median = 22.4, SD = 11.9. The internal reliability for the nine-item scale was satisfactory (alpha = 0.88). Following this, we then performed a multiple regression analysis with backwards elimination of covariates to examine the extent to which expectations to change drinking behavior (expectations total score) could be predicted by age, gender, subjective norms, methadone dose, the number of days of alcohol use in the last month, perceived functions for alcohol use (total score), and attitudes toward alcohol Table 1 Prevalence of drinking to fulfil specific functions (n = 50) Function
%
To To To To To To To To To
84 68 66 64 54 30 28 24 24
help to relax stop feeling bored make yourself feel better when low or depressed forget problems help to get to sleep increase the effects of methadone or any other drug help to ‘‘get going’’ in the morning stop feeling sick in the morning calm after using other drugs
consumption. While the cases to covariates ratio was 7:1, which exceeds a minimum to perform multiple regression analysis, given the small sample size this analysis should be seen as preliminary and exploratory. Four variables appeared to predict expectations to change drinking behavior. The strongest was subjective norm, which was positively related to expectations to change drinking behavior. The other variables in order of strength of effect were as follows: perceived functions of alcohol use; the number of days used alcohol in the last 30 days; and dose of methadone had significant regression coefficients. These variables were negatively related to the expectation measure. Overall, 51% of the variability in expectation to change aspects of alcohol consumption over the next 6 months was predicted by knowledge of scores of subjective norm, perceived function of alcohol use and dose of methadone.
4. Discussion The aim of the present study was to examine the prevalence of alcohol use and alcohol dependence among clients receiving MMT at a London clinic and explore their alcohol-related expectations. The levels of alcohol consumption were varied, but generally quite substantial, with 76% of the sample having consumed at least one alcoholic drink in the last 30 days and with current drinkers, 41% meeting DSM-IV alcohol dependence diagnostic criteria for the preceding 12 months. Different investigators have used different instruments and thresholds to assess alcohol use and abuse, and this has created difficulties in comparing results across studies. One study from the United States, using a criterion employing positives among five DSM-III-R equivalent items to diagnose alcohol dependence among clients in MMT, reported a cohort prevalence of 9.2% (Chatham et al., 1995). This percentage appears low compared to the rate found in the present investigation. However, Chatham et al. (1995) defined alcoholism by at least three positive responses to only five DSM-III-R items, which provides a conservative estimation. Although a more liberal criterion was used in the present study, it was clear that symptoms related to alcohol dependence were common. Our study also investigated the extent to which clients believed they would make changes to their drinking behavior during the next 6 months. Nearly 40% of the sample reported that, during this period they considered they would try to avoid consuming strong alcoholic beverages and around one-third reported they would try to avoid drinking with certain people, to avoid drinking in certain places, to reduce their weekly level of consumption and to avoid drinking alone. Using the framework of the TRA, we conducted an exploratory regression analysis to model variations in their expectancy behaviors and were able to account for 51% in rating scale variability using a set of seven covariates. The strongest positive predictor of expectations was subjective norms, suggesting that the more that
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‘‘important others’’ think a client should change his/her drinking behavior over the next six months, the more clients expect to see themselves change these aspects. This finding is surprising since most previous research has reported that intentions tend to be more under attitudinal control than under normative influence (O’Callaghan et al., 1997; Schlegel, Crawford, & Sanborn, 1977). In fact, attitudes toward alcohol did not appear to predict change expectancies to any great extent. Although the finding is preliminary due to the small sample size in this study, it provides some suggestions on how problematic alcohol use might be reduced among methadone maintenance clients. One possible explanation for the importance of subjective norm stems from the hypotheses that opioid dependent clients are apt to be more under normative control due to their previous history of drug and drug associated problems. Because of these problems they represent a vulnerable group with possible low self-esteem and this could be a reason they are more prone to normative influences. Therefore, MMT program staff should be alert to the insights that may be derived from exploration of their clients’ self-concepts and possible implications with regard to concurrent drug consumption and overall social and emotional functioning. The second strongest predictor of future expectations was perceived functions of alcohol use. The more frequently clients perceived their alcohol use as serving specific functions, the less likely they were to expect to change their alcohol use pattern. We suggest that this preliminary finding, if replicated in further studies, has important clinical implications for tackling alcohol problems in MMT. Following an assessment of a specific alcohol use function reported by a client, help should be provided to develop alternative ways of fulfilling these functions. In the present study, drinking to relax, to alleviate boredom and to improve negative mood were all commonly cited. The clinician who elicits the active presence of these functions in a particular client should then plan the incorporation of relevant additional psychological and social support to supplement the standard MMT program. This might be of particular importance for those clients who are dependent on alcohol, whom we found drank more often alone or with friends at home. Ways of engaging clients in wider activities to fulfill these functions should be incorporated into the overall medical, psychological and social treatment plan for their care. Other functions that were less common among this sample might also be of importance for individual clients and need to be explored by the clinician. In particular, the use of alcohol to increase the effects of methadone should be closely examined in routine clinical practice. Further work is needed to examine this behavior and to assess the levels of alcohol consumed and methadone dose taken. Since combined CNS depressant use has been linked to cases of opioid overdose (Strang et al., 1999), clients who drink heavily while in MMT treatment may be at risk, and drinking to increase the effects of methadone should be
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assessed and discussed as part of ongoing care planning and review. We also suggest the clinician should assess the particular client’s expectations to change alcohol use behaviors in the near future. This would provide the opportunity to explore anticipated problems the client might have to change certain drinking behaviors. Another implication for treatment concerns the influence of ‘‘important others’’ who are currently often neglected in the treatment process. Additional variance in expectations to change aspects of alcohol use was accounted for by negative relationships with past alcohol use and current daily dose of methadone. This suggests that the more days a client consumes alcohol in the last 30 days, the less he or she expects to change alcohol use behavior in the short term. A higher dose of methadone was also associated with reduced likelihood of changing alcohol use over the next 6 months. It may be that clients with relatively higher doses of methadone are more attached to drinking behavior, and are less likely to wish to alter their drinking pattern. This interpretation is speculative and the relationship between dose of methadone and motivation for alcohol use should be clarified in future research. Several limitations to the study need to be borne in mind. First, the use of retrospective self-report data on alcohol consumption restricts the validity of the results and we were not able to conduct an independent validation. Second, the sample was small in size and should be repeated with a more substantial group and in other localities. Third, no information was obtained of the extent to which alcohol issues are already being adequately addressed within the methadone treatment program itself. Future research in this area should consider these limitations and explore who could be the key persons to change each individual client’s expectations. Overall, the present study confirms previous research that has documented the substantial extent of, and lack of treatment for alcohol related problems that occur among patients in methadone maintenance (El Bassel et al., 1993). Among our sample, only one client was currently receiving treatment for their alcohol dependence. A stronger focus on the treatment of polydrug use in methadone maintenance services and a close cooperation with other services and AA groups could be important first steps to combat this insufficiency. The results from this study also point to the need for methadone prescribing programs to make a concerted effort to assess and respond to heavy drinking and alcoholrelated problems among their clients.
Acknowledgments The authors express their thanks to the staff and clients of the South London Methadone program for their support and assistance during the study. Grant support was provided by the National Addiction Centre. The study was substantially undertaken as the research project for the M.Sc. in Clinical
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and Public Health Aspects of the Addictions (University of London) at the National Addiction Centre by the lead author (J. Hillebrand).
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