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Drug Alcohol Depend. Author manuscript; available in PMC 2012 June 26.
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Published in final edited form as:
Drug Alcohol Depend. 2010 February 1; 107(1): 23–30. doi:10.1016/j.drugalcdep.2009.08.021.
Effect of Motivational Interviewing on Reduction of Alcohol Use
Adeline Nyamathi,
University of California, Los Angeles, School of Nursing, 2-250 Factor, Box 951702, Los Angeles,
CA 90095-1702, (310) 825-8405, (310) 206-7433,
[email protected]
Steven Shoptaw,
University of California, Los Angeles, Department of Family Medicine and Psychiatry, 10880
Wilshire Blvd., Los Angeles, CA 90095-7087, (310) 794-0619x225,
[email protected]
Allan Cohen,
Director of Research and Training, Bay Area Addiction, Research and Treatment, Inc., 1926 W.
Beverly Blvd. Los Angeles, CA 90057, (213) 607-0210, (310) 607-1434,
[email protected]
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Barbara Greengold,
University of California, Los Angeles, School of Nursing, 3-133 Factor, Box 956917, Los Angeles,
CA 90095-6917, (310) 794-4814, (310) 267-0413,
[email protected]
Kamala Nyamathi,
University of California, Davis, School of Medicine, One Shields Avenue, Davis, California 95616
Mary Marfisee,
University of California, Los Angeles, David Geffen School of Medicine, 1920 Colorado Avenue,
Los Angeles, CA 90095-7087, (818) 947-4095,
[email protected]
Viviane de Castro,
University of California, Los Angeles, School of Nursing, 3-133 Factor, Box 956917, Los Angeles,
CA 90095-6917, (310) 794-4814, (310) 267-0413,
[email protected]
Farinaz Khalilifard,
University of California, Los Angeles, School of Nursing, 3-133 Factor, Box 956917, Los Angeles,
CA 90095-6917, (310) 794-4814, (310) 267-0413,
[email protected]
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Daniel George, and
Director, Matrix Institute on Addictions, 12304 Santa Monica Blvd., Los Angeles, CA 90025,
[email protected]
Barbara Leake
© 2009 Elsevier Ireland Ltd. All rights reserved.
Correspondence should be addressed to: Adeline Nyamathi, ANP, Ph.D., FAAN, UCLA, School of Nursing, Room 2-250, Factor
Building, Box 951720, Los Angeles, CA 90095-1702, (310) 825-8405, phone,
[email protected].
Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our
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Contributors:
Barbara Greengold and Steve Shoptaw contributed to writing the review of literature and introduction. Adeline Nyamathi, and Mary
Marfisee contributed to the methods and discussion. Allan Cohen, Kamala Nyamathi, Viviane de Castro and Daniel George
contributed to the editing and final review of the manuscript. Barbara Leake provided the statistical analysis. All authors approved the
final paper.
Conflict of Interest:
All authors declare that they have no conflicts of interest.
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University of California, Los Angeles, School of Nursing, 3-669 Factor, Box 956917, Los Angeles,
CA 90095-1702,
[email protected]
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Abstract
Background—Methadone-Maintained (MM) clients who engage in excessive alcohol use are at
high risk for HIV and Hepatitis B virus (HBV) infection. Nurse-led Hepatitis Health Promotion
(HHP) may be one strategy to decrease alcohol use in this population.
Objective—To evaluate the impact of nurse-led HHP, delivered by nurses compared to
Motivational Interviewing (MI), delivered by trained therapists in group sessions or one-on-one on
reduction of alcohol use.
Methods—A three-arm randomized, controlled trial, conducted with 256 MM adults attending
one of five MM outpatient clinics in the Los Angeles area. Within each site, moderate-to-heavy
alcohol-using MM participants were randomized into one of three conditions: 1) nurse-led
hepatitis health promotion group sessions (n=87); 2) MI delivered in group sessions (MI-group;
n=90), or 3) MI delivered one-on-one sessions (MI-single, n=79).
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Results—Self-reported alcohol use was reduced from a median of 90 drinks/month at baseline to
60 drinks/month at six month follow-up. A Wilcoxon sign-rank test indicated a significant
reduction in alcohol use in the total sample (p < .05). In multiple logistic regression analysis
controlling for alcohol consumption at baseline and other covariates, no differences by condition
were found.
Discussion—As compared to two programs delivered by MI specialists, a culturally-sensitive
and easy to implement nurse-led HHP program produced similar reductions in alcohol use over six
months. Employing nurse-led programs may allow cost savings for treatment programs as well as
a greater integration of alcohol reduction counseling along with a more comprehensive focus on
general health-related issues than previously conducted.
Keywords
Alcohol use; Methadone Maintained; Motivational Interviewing; nurse-led hepatitis health
promotion
1.0 Introduction
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Methadone-Maintained (MM) clients have reported excessive alcohol use; in fact, nearly
50% of this population has reported chronic alcohol consumption (Maremmani et al., 2007).
Alcohol abuse has been associated with major health problems, including hepatic cirrhosis
and hepatocellular carcinoma (Srivastava et al., 2008). Alcohol-abusing MM clients suffer
from psychological impairments, including anxiety and feelings of low moods, and poor
social functioning (Senbanjo et al., 2007). Alcohol use and abuse are also correlated with
chronic drug use (Backmund et al., 2003); both types of substance use place individuals at
risk for HIV and hepatitis (Arasteh et al., 2008). Moreover, among MM clients who have
hepatitis C (HCV), reduction and/or elimination of alcohol drinking is an important
treatment goal as it would decrease demand on liver enzymes and perhaps slow HCV
disease progression.
To date, no studies exist which assess the impact of brief alcohol reduction among patients
enrolled in methadone maintenance programs. Currently, the most popular intervention
which has shown an impact on reducing alcohol use is Motivational Interviewing (MI), a
‘client-oriented counseling style’ that seeks to help clients ‘explore and resolve
ambivalence’ to change (Miller and Rollnick, 2002). MI has been found to be an effective
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strategy in reducing alcohol use and abuse among a variety of populations, when delivered
by therapists one-on-one or the less evaluated group approach (Deas, 2008; Peterson et al.,
2006).
The impact of intervention directed at reducing alcohol use by health care providers who
traditionally provide care and support is nevertheless of interest. In particular, nurses can
have a significant potential to change behavior when interacting with addicts who are
enrolled in methadone maintenance programs, as these environments provide an excellent
arena for developing health promoting behaviors among high risk populations. While no
research has been conducted that has focused on reducing alcohol use among the methadone
population to date, nurse-led interventions have resulted in reduction of alcohol use among
general hospitalized patients (Tsai et al., 2009) and among postpartum women (Fleming et
al., 2008). Lock et al. (2006) believes that as one of the key roles of the nurse is to promote
health, and nurses have a lower cost of employment than physicians, nurses are ideally
suited to deliver brief alcohol interventions.
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To date, there have been no studies specifically looking at the comparative efficacy of nurseled intervention, nor MI, delivered either individually or in a group setting among adults
receiving MM. The present study evaluates the efficacy of nurse-led Hepatitis Health
Promotion (HHP) group sessions against the already established intervention MI. In
addition, the study presents a unique opportunity to evaluate group MI compared to
individual MI; the former of which possesses only a little, albeit growing, evidence for its
efficacy compared to individual MI. Comparing these two MI interventions (Group vs
individual) is also important because of the predominance of group therapy in substance
abuse treatment and the fact that more studies are needed evaluating group therapy.
1.1 Theoretical Basis for Nurse-Led Intervention
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The Comprehensive Health Seeking and Coping Paradigm (CHSCP; Nyamathi, 1989),
originally adapted from Lazarus and Folkman’s (1984) stress and coping paradigm and
Schlotfeldt’s (1981) health-seeking paradigm, proposes that a number of factors impact
health outcomes of vulnerable populations with health disparities (Nyamathi et al., 2003;
2006; 2008). These factors include sociodemographic characteristics, personal and
psychosocial resources and health behaviors, cognitive appraisal, coping responses, nursing
strategies, and health outcomes. In this study, variables of interest include sociodemographic
factors (age, ethnicity, gender, education, recruitment site), personal (physical health status
factors), psychosocial factors (depressive symptomotology, poor emotional well being,
social support) resources, type of intervention (MI-group, vs MI-single, vs Nurse-led HHP
programs) and behavior (alcohol use, injection and non-injection drug use, traded sex,
multiple partners, HBV vaccination initiation).
1.2 Nurse-Led Interventions
Several studies have demonstrated that nurse-led interventions seeking to reduce alcohol
consumption among high-risk substance abusers are effective (Cummings et al., 2006;
Flemming et al., 2008; Tsai et al., 2009). In a study a brief intervention delivered by nurses
for problem drinkers in a Chinese hospitalized population, Tsai et al. (2009) revealed
significant decreased alcohol scores at 12 month follow-up compared top a control group.
Among a sample of 235 postpartum women screened as having “at-risk” drinking problem,
the findings of a brief intervention offered by obstetric nurses revealed a significant
reduction in mean number of drinks in the past 30 days, and number of drinking days and
heavy drinking days in the past 30 days (Fleming et al., 2008).
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These findings support the need for widespread screening and brief intervention for
populations at risk for poor maternal-child outcome. In yet another nurse-delivered clusterrandomized controlled trial (Lock et al., 2006), no differences were found between the
intervention and control groups. The authors contend that the high drop-out rate of over 50%
may have resulted in lack of positive findings. These findings highlight the fact that nurseled interventions have high potential for reducing substance use among at-risk populations
and would be worthy of testing in a methadone-maintained population as well.
1.3 Motivational Interviewing
Although MI has been applied to various areas of health behavior change, including obesity,
HIV risk factor modification and eating disorders, the broadest application of this approach
has been in the area of addiction (Hettema et al., 2005). MI has been effective for the
reduction of alcohol use among adults attending community health centers in Idaho
(Beckham, 2007) and has been shown to effectively reduce illicit drug use among homeless
adolescents (Peterson et al., 2006). Among college students, several studies have shown the
effectiveness of MI in the reduction of drinking (Deas, 2008), particularly heavy drinking
(Juarez et al., 2006; LaBrie et al., 2007a). However, MI has not consistently resulted in
measurable improvement (Hettema et al., 2005). For example, in a recent study of homeless
adolescents, MI was not associated with reduction of alcohol use (Baer et al., 2007).
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Currently, there is a paucity of studies comparing outcomes when MI is delivered using
individual versus group format for the management of alcohol abuse; moreover, the
populations in which the studies have been conducted were quite disparate and mixed.
Individually-delivered interventions using MI have been found most effective for the
management of alcohol abuse among college students (Carey et al., 2007). However, brief,
individual MI, delivered on a one-time basis to alcohol-abusing inpatients was not found to
be associated with reductions in alcohol use (Saitz et al., 2007). Grenard et al. (2006) found
that one-to-one sessions have been shown to be effective among adolescents and young
adults engaged in drug-related behaviors. Group MI has also been shown to be effective in
reducing alcohol use among both psychiatric inpatients with chemical dependence (Santa
Ana et al., 2007) and female college students (LaBrie et al., 2007a). On the other hand, John
et al. (2003) found no significant difference in amount of alcohol reduction when comparing
individual to group MI among a group of alcohol-dependent inpatients.
The purpose of this trial is to evaluate the impact of a nurse-led hepatitis health promotion
program in reducing alcohol use among participants receiving methadone maintenance, to
an already established, empirically supported intervention (MI) and also to evaluate how the
nursed-led HHP differs from either MI method.
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2.0 Method
This study was a randomized controlled trial of a three-group intervention with 256
moderate and heavy alcohol-using adults receiving MM treatment in Los Angeles. After
completion of a structured baseline questionnaire administered by trained research staff, all
participants who self-reported moderate- to-heavy alcohol use were randomized into one of
three programs: Motivational Interviewing -Single (MI-Single), Motivational InterviewingGroup (MI-Group), or Nurse-Led Hepatitis Health Promotion (HHP). MI sessions were
delivered by two trained therapists specialized in the facilitation of MI. The Nurse-led HHP
sessions were delivered by a research nurse in conjunction with a trained research staff
member. Each program provided three sessions, as well as the HAV/HBV vaccination series
for all those found to be HBV seronegative. Baseline data were collected from February
2007 to May 2008. Follow-up data were collected six months later.
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2.1 Sample and Setting
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MM clients met eligibility criteria if they had received methadone for at least three months,
were 18–55 years of age, and reported moderate-to-heavy alcohol use based on questions
from the Addiction Severity Index (ASI). Recruitment was conducted in five MM treatment
sites in Los Angeles and Santa Monica. These sites included: Bay Area Addiction (BAART)
clinics in the areas of Beverly, Southeast, and Lynwood, and non-BAART MM sites in
Santa Monica (Matrix) and Southeast Los Angeles (TriCity).
2.2 Procedure
The study and associated materials were approved by the Human Subject Protection
Committee. In addition, this study is registered with clinicaltrials.gov, registration
#NCT00926146. Upon obtaining written permission from the directors to collect data at the
selected sites, participants were recruited by means of posted flyers. For those interested,
after informed consent for the screening had been read and signed in a private room in the
sites, the outreach workers administered a brief two-minute structured questionnaire
composed of socio-demographic characteristics, a screen for alcohol use and severity, and a
hepatitis-related health history.
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After the initial screening was completed, detailed information was provided about the study
to eligible persons and a second-level consent for blood testing was requested. MM clients
who met eligibility criteria and wished to participate further completed a third consent form
prior to enrollment into the study.
2.3 Measures
Socio-Demographic information, collected by a structured questionnaire, included age,
gender, birthdate, ethnicity, education, childhood physical abuse, history of substance abuse
treatment, and history of trading sex lifetime.
HBV Vaccination Status was measured as receipt of any dose of the Twinrix vaccine.
Although the vaccination was not expected to directly influence alcohol reduction, extra
time and attention were required to administer it.
Perceived Health Status was measured on a 5-point scale from “excellent” to “poor” and a
dichotomous item inquired about past six-month hospitalization. Health status was
dichotomized at fair/poor versus better health.
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Depressive Symptoms were assessed with the Center for Epidemiological Studies
Depression (CES-D) scale (Radloff, 1977) and has been validated for use in homeless
populations (Nyamathi et al., 2006; 2008). The 10-item self-report instrument is designed to
measure depressive symptomology in the general population (Andresen et al., 1994) and
measures the frequency of a symptom on a 4-point response scale from 0 “Rarely or none of
the time (Less than 1 day)” to 4 “All of the time (5–7 days)”. Scale scores were
dichotomized at a cutoff value of 8, a frequently used figure to suggest depressive
symptomatology. The internal reliability of the scale in this sample was .80.
Emotional Well-Being was measured by the five-item mental health index (MHI-5); this
scale has well-established reliability and validity (Stewart et al., 1988). Scores were linearly
transformed so that they ranged from 0 to 100. A cut-point of 66 (Rubenstein et al., 1989)
was used to discriminate participants’ emotional well-being. Cronbach’s alpha for the scale
in this study was .79.
Social Support was measured by a 9-item scale used in the RAND Medical Outcomes Study
(Sherbourne and Stewart, 1991). The items elicited information about how often respondents
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had friends, family or partners available to provide them with food, a place to stay, etc, on a
five-point Likert scale. The instrument has demonstrated high convergent and discriminant
validity; internal consistency reliability coefficients range from 0.91 to 0.97 for the
subscales (Sherbourne and Stewart, 1991). Cronbach’s alpha for the scale in this study was .
94. An additional question inquired about whether social support came primarily from drug
users, non-drug users or both.
For this study, alcohol use was assessed by the Time Line Follow Back that assessed the
number of standard drinks consumed per day over the last 30 days.
Drug use was measured by the Addiction Severity Index – Lite Version. This measure is a
shortened version of the ASI (5th edition – McClellan et al., 1992). Drug use was
dichotomized at its median for clarity of presentation in this study.
2.4 Intervention
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Nurse-Led Hepatitis Health Promotion (HHP) Program. At baseline, a nurse and Hepatitistrained research assistant conducted three time-equivalent (60 minute) HHP group sessions.
These staff were well trained on the integration of the CHSCP into their education delivery.
Each session was spaced two weeks apart; thus, the three sessions were delivered within six
weeks of entry into the program. The average number of participants was six; however
groups ranged from 5–7 in number.
The HHP sessions focused on hepatitis education, specifically, the progression of HCV
infection and the culturally-sensitive strategies that infected individuals can adopt to prevent
or reduce accumulated damage to liver functioning. Utilizing the principles of the CHSCP,
this intervention by nursing integrated strategies which included discussing the dangers of
alcohol use on hepatitis (cognitive factors), discussing ways to avoid alcohol and other
drugs, eating a balanced diet, dangers of reinfection of HCV by resuming injection drug use
(IDU), receiving unsafe tattoos and body piercing, having unprotected sexual behavior, and
being consistent in engaging in other health-related behaviors, such as regular medical
check-ups (behavioral factors). Additional health promoting activities included strategies in
enhancing coping (coping factors), such as seeking social support of a positive nature,
getting support from religion and building self esteem (personal and psychosocial factors)
when afflicted with a history of drug and alcohol addiction. The HHP program was directed
by a detailed protocol to maintain fidelity of the program and prevent the HHP team from
moving into MI-type approaches. While the didactic delivery style was utilized, the sessions
were interactive as the group raised questions about the content.
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Motivational Interviewing Program (Individual vs Group). After completion of the baseline
questionnaire, eligible participants randomized into the MI group were offered three, 60minute sessions that were delivered (one-on-one or via group format) by trained MI
specialists with the same delivery timing and number of clients in the group session as the
HHP sessions. The MI specialists included a PhD-prepared psychologist who conducted
primarily the MI-group sessions and a MSW-prepared researcher who conducted primarily
the individual MI sessions. The psychologist was trained by experts in MI and has had over
15 years experience in facilitating MI in clinical practice with drug addicted clients. The
MSW-prepared researcher had over two years training in MI facilitation by a MI-trained
psychologist. MI sessions included MI spirit (e.g., collaboration, evocation, autonomy), MI
principles (e.g., empathy, rolling with resistance, developing discrepancy, enhancing selfefficacy) and MI microskills (e.g., eliciting change talk, reflections and affirmations). MI
sessions were focused on exploring the impact alcohol use had on health and risky
behaviors, and working through ambivalence to reduce alcohol use while focusing on
subsequent life goals. Content in the group vs one-on-one MI sessions were identical and the
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delivery of each session was guided by a detailed protocol and bi-weekly meetings with the
investigator and therapists which enhanced treatment adherence and fidelity by the
therapists. The sessions were open; thus allowing participants who had not completed their
three sessions with their original cohort to complete with a later cohort.
Regardless of group, both HHP and MI Single or Group sessions were preceded by a needs
assessment and included referrals and appointments as needed for medical and mental health
services. All participants received a small incentive for each of three sessions ($5); and a
Local Community Resource Guide. For both HHP and MI programs, subsequent to the
sessions, the three-series HAV/HBV vaccine was administered by the research nurse, if the
participant was eligible for the vaccine (HBV sero-negative and no history of allergies) and
desired to be vaccinated. All participants also received referrals to 12-step alcohol treatment
programs in the community. Moreover, participants were notified to return for their sixmonth follow-up questionnaire and the last vaccine dose, for those receiving the vaccine
series.
2.5 Data Analysis
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All analyses were intent-to-treat. The primary outcome was at least 50% reduction in
alcohol use by six-month follow-up. Additionally, we examined abstinence from alcohol use
at six months. Preliminary analyses, including chi-square tests, t tests, analysis of variance
and correlations, were used to assess comparability of the three programs at baseline and to
examine unadjusted correlates of a 50% or greater reduction in alcohol use. Multiple logistic
regression modeling was used to assess program effects on 50% alcohol reduction,
controlling for potential confounders. Six people reporting no alcohol use at baseline,
despite moderate-to-heavy alcohol use on the screener were excluded from this analysis; as
were a few participants with mixed or “other” ethnicity. Stepwise backward multiple logistic
regression analysis was used to create a model of alcohol reduction; predictors included
variables that were associated with 50% alcohol use reduction at the 0.15 level in
preliminary analyses. Indicators for MI-single and MI-group assignment and baseline
alcohol use, categorized into quartiles due to non-normality, were included in all models;
other covariates were retained if they were significant at the .10 level.
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Multicollinearity was assessed and model fit was examined with the Hosmer-Lemeshow
test. More specifically, we addressed the lack of independence by using the “fixed effects
approach to clustering”, as recommended by Snijders and Bosker (1999), among others,
when the number of clusters (sites) is small (e.g., <10). To control for differences among the
means of the 5 sites, we tested dummy variables for 4 of the sites in a final regression
model. Since the results did not differ substantively, we present the more parsimonious
model. Statistical analyses were performed with SAS/STAT.
3.0 Results
Compilation of the sample is as described in Table 1. A total of 256 MMT participants were
randomized into the MI-S (n = 90), MI-G (n = 79) or Nurse-led HHP (n = 87) group. A few
participants (n = 6) reported no alcohol use in the past month at baseline. As shown on Table
1, more than half the sample (59%) was male and predominantly African American (45%)
or Latino (27%). About one-third of participants received social support from both drugusers and non-drug users, while almost half reported social support from primarily non drug
users. A total of 86.7% of participants completed all three sessions and 91.3% completed the
six month follow-up (Figure 1).
At baseline, half of the sample reported 90 standard alcoholic drinks or more in the past
month. In terms of drug use, 40% reported current IDU; only about one in five reported
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attending recent self-help programs. There were no group differences in subject
characteristics at baseline with respect to program type. Health and health behaviors in this
sample were found to be suboptimal. One quarter of the sample reported physical abuse in
childhood and over a third said they had participated in sex trade. Symptoms of mental
illness were common, with 80% reporting depressive symptoms and over two-thirds
reporting poor emotional well being.
3.1 Alcohol Use Reduction
As shown in Table 1, about half the sample reported at least a 50% reduction in alcohol use
and slightly more than one in five reported no alcohol use at six month follow-up. However,
there were no statistically significant condition differences in either 50% reduction in
alcohol use or abstinence from alcohol at six months follow-up. Compared to their
counterparts who failed to reduce alcohol use by 50%, those who were able to reduce
successfully were more likely to be African American (40% vs 52%, p < .05) and more
likely to be the highest quartile of baseline drinking (14% vs 35%, p < .001) (Table 2).
3.2 Multivariate Results
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Adjusting for potentially confounding characteristics did not affect the preliminary findings
of no condition differences in alcohol reduction (Table 3). Baseline alcohol use was the most
important correlate of 50% alcohol reduction. Women had greater odds of reducing their
alcohol use by at least 50% than men. More education and having received at least one dose
of the HBV vaccine, with concomitant time and attention, were also associated with alcohol
use reduction. Participants with drug-using partners and those who reported using marijuana
on at least two days in the last 30 had lower odds of 50% alcohol reduction than their
counterparts.
4.0 Discussion
As a result of high rates of chronic consumption of alcohol use among methadone
maintained persons, the need to assess programs which focus on brief alcohol reduction at
the program site is great. This study was designed to study the effectiveness of a nurse-led
intervention as compared to an already established intervention, MI. In addition, this study
presented a unique opportunity to evaluate group MI compared to individual MI, as little is
known of the efficacy of group MI when compared to the larger evidence base that
individual MI possesses. Comparing these two MI interventions is also important because of
the predominance of group therapy in substance abuse treatment and that more studies are
needed evaluating group MI.
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The major finding of this study was that all three interventions resulted in significant
reductions in drinking behavior at six-month follow-up. Specifically, over a six-month
period of intervention, about half of the total sample reported at least a 50% reduction in
alcohol use and about 20% reported no alcohol use at six month follow-up. There were no
significant differences found among treatment groups with respect to drinking reduction.
While MI has been shown to be effective for the management of problem drinking among
college students (Deas, 2008; White et al., 2007; LaBrie et al., 2007b), and homeless
persons (Baer et al., 2007; Peterson et al., 2006), we found no evidence of differential
efficacy of one-on-one vs group-delivered MI over a nurse-led intervention in reducing
alcohol drinking. Nurse-led interventions have been found to be effective for the
management of alcohol-related problems among adults (Lock et al., 2006; Smith et al.,
2003). Although there have been no studies designed to investigate the effectiveness of the
same intervention, delivered by different practitioners such as nurses, physicians, social
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workers or clinical psychologists (Finfgeld-connett, 2005), Littlejohn and Holloway (2008)
believe that nursing interventions are highly warranted for the prevention of alcohol abuse.
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Our study also showed that MI, delivered by trained therapists, either in group sessions or
via one-on-one sessions did not differ in effectiveness from each other, and neither were
more effective than a nurse-led HHP program, for the reduction of alcohol use. While there
is a paucity of studies which have examined relative effect of one-to-one MI sessions
compared to group MI sessions, both methods have been found to be effective in the
management of alcohol abuse. In particular, one-to-one MI has been shown to be an
effective intervention among medical inpatients (Saitz et al, 2007), and group MI has been
found to be beneficial among college women (LaBrie et al, 2007a) and psychiatric inpatients
(Santa Ana et al., 2007). However, the majority of trials have compared MI (delivered in a
group or on a one-to-one basis) to other interventions such as cognitive behavioral therapy,
and therapies based on social-cognitive, self-regulation, and self-determination theories
(Carey et al., 2007). To date, we do not know of any study comparing one-to-one MI with
group MI in the management of problem drinking for methadone maintained clients.
Moreover, no studies have compared these two types of MI delivery styles with nurse-led
programs. Our study is the first to compare MI delivery (one-to-one versus group) with a
nurse-led intervention. As the nurse-led HHP sessions were found to be as effective as MI
sessions, further studies of the efficacy and cost-effectiveness of nurse-led management of
problem alcohol use is highly warranted.
We also found that African Americans were more likely to reduce alcohol consumption by
at least 50% compared to their ethnic counterparts. While ethnic differences were not
previously reported among MM populations who attempted to reduce their alcohol
consumption, these findings are consistent with those from a study which showed that
African American college students more regularly employed drinking reduction strategies
(with the exception of choosing a designated driver), compared with White college students
(Siebert et al., 2003). Further investigation is warranted to assess whether ethnic differences
are important in enabling further reduction of alcohol among a diverse sample of MM
clients.
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Logistic regression findings revealed that heavier alcohol drinkers were more likely to
reduce alcohol use by 50%. Our results are concordant with those reported by Walton et al.
(2008) where participants who were most ready to reduce their alcohol intake had higher
pre-intervention alcohol intake, compared with those who consumed less. Clearly,
participants who used higher amounts may have been more able to reduce alcohol use rather
than to stop drinking completely. However, among individuals affected by or at high risk for
hepatitis, total cessation of alcohol use is recommended. Thus, strategies to enhance the
cessation of any amount of alcohol use is needed.
Our results also showed that being female and having higher levels of education were
associated with greater reduction in alcohol consumption. Consistent with other findings,
males have been found to be higher consumers of alcohol compared with women
(Livingston and Room, 2009). While there are no studies showing that females respond
more effectively than males to MI therapy, or to nurse-led interventions in the management
of alcohol abuse, gender differences have been found with respect to the risk factors and
consequences of alcohol abuse (Nolen-Hoeksema, 2004). Men and women with histories of
abuse (sexual, emotional or physical) have also been found to experience different rates of
recovery, with respect to substance abuse treatment (Branstetter et al., 2008). We believe
that the results of our study, in conjunction with the findings from the studies cited above,
suggest that women may respond differently to therapy than men.
Drug Alcohol Depend. Author manuscript; available in PMC 2012 June 26.
Nyamathi et al.
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Another important finding was that participants who had one or more of the three series
Twinrix hepatitis vaccine were more likely to reduce alcohol use by at least 50%. While this
finding has never been reported in the literature, we believe that the extra time and attention
taken to explain the vaccine and to administer the injection was an important factor resulting
in alcohol reduction. Kaminer et al (2008) reported that programs of aftercare, which
consisted of multiple in-person or telephonic follow-up slowed post-treatment relapse
among adolescents. Programs of aftercare and interventions such as ours, both involve extra
time and attention on the part of therapists and this may lead to better client outcomes.
In our study, recent marijuana users were least likely to reduce alcohol use. This is
consistent with the findings from another study showing that alcohol use, in conjunction
with marijuana use, was associated with poorer outcomes, compared with alcohol use alone
(Rhodes et al., 2008).
NIH-PA Author Manuscript
One study limitation was that our interventions, one-to-one MI, group-MI, and a nurse-led
hepatitis prevention program were delivered by a heterogeneous group of practitioners. The
internal validity of our study could have been enhanced if we compared nurse-led MI to
nurse-led hepatitis prevention. Another study limitation was the fact that we recruited
volunteers into our study who may have been motivated for treatment as well as used selfreport to measure treatment effect. Self-report can be subject to bias which may threaten the
validity of the study. Finally, while we did not audio-tape the sessions or utilize a checklist
to assess for fidelity, a detailed treatment protocol was followed and bi-weekly meetings
were held with the investigator and therapists throughout the study to provide feedback and
supervision to maintain the treatment protocol and its delivery.
In summary, this study is the first to compare nurse-led HHP to two methods of MI (one-toone and group) for the management of problem drinking, among people undergoing MM
therapy. All three interventions resulted in significant reductions in alcohol drinking
behavior. Implications of employing MI group vs MI individual clearly may result in cost
savings for treatment programs. More importantly, employing nurse-led programs may not
only allow cost savings as well but also allow a greater integration of alcohol reduction
counseling along with a more comprehensive focus on general health-related issues than
previously conducted. It has been suggested that nurses can play a significant role in
management of alcohol abuse (Littlejohn and Holloway, 2008). We have been able to
demonstrate that nurses can be as effective as other practitioners in the management of
excessive alcohol use. We believe that further studies of the efficacy and cost-effectiveness
of nurse-led management of problem alcohol use is highly warranted.
NIH-PA Author Manuscript
Acknowledgments
The authors would like to thank Cindy James for her assistance with the manuscript preparation.
Role of Funding:
Funding for this study was provided by NIAAA Grant AA015759. The NIAAA had no further role in study design;
in the collection, analysis and interpretation of data; in the writing of the report; or in the decision to submit the
paper for publication.
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Figure 1.
Description of the Sample. a. Methadone Maintained. b. Alcohol Severity Index. c.
Motivational Interviewing – Single. d. Motivational Interviewing – Group. e. Nurse-led
Hepatitis Health Promotion. f. Follow-up.
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Table 1
Characteristics
MI-Single
MI-Group
(N = 90)
Background
Drug Alcohol Depend. Author manuscript; available in PMC 2012 June 26.
Mean Age
HHP
(N = 79 )
Mean
SD
Mean
51.9
(7.9)
50.0
SD
(7.4)
Total
(N = 87 )
Mean
51.8
SD
(8.8)
(N = 256 )
Mean
SD
51.2
(8.4)
%
%
%
%
60.0
58.2
59.3
59.2
African American
46.7
44.3
44.2
45.1
White
21.1
24.1
11.6
18.8
Latino
25.6
25.3
29.1
26.7
Other
6.7
6.3
15.1
9.4
High School Grad
62.2
59.5
52.3
58.0
Partnered
51.7
55.7
55.8
54.3
Employed
18.0
12.7
20.9
17.3
Beverly
16.9
21.8
23.8
20.7
Southeast
31.5
37.2
28.6
32.3
Lynwood
9.0
9.0
8.3
8.8
Matrix
28.0
23.1
23.8
24.7
TriCity
15.7
9.0
15.7
13.6
58.9
63.3
59.3
60.4
Male
Nyamathi et al.
Baseline Sample Characteristics of Methadone Maintained Clients by Program
Ethnicity:
Recruitment Site:
Fair/poor health
Childhood Physical Abuse
23.3
27.9
24.4
25.1
Lifetime Trade Sex
31.8
46.7
32.9
36.7
0–40++
23.3
27.9
24.4
25.1
41–89
21.1
22.8
30.2
24.7
90–180
32.2
22.8
24.4
26.7
Substance Use
Recent +Alcohol Use at
Baseline
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Characteristics
MI-Group
HHP
Total
(N = 90)
(N = 79 )
(N = 87 )
(N = 256 )
23.3
26.6
20.9
23.5
Recent+ marijuana use
17.8
25.3
5.8
16.0
Recent+ IDU
37.8
45.6
37.2
40.0
Drug Alcohol Depend. Author manuscript; available in PMC 2012 June 26.
Smoke ≥1 pack/day
52.2
64.6
52.3
56.1
Recent+ Self-Help
23.3
25.3
15.1
21.2
≥50% reduction in
alcohol use at six months
46.6
54.0
49.4
49.8
No recent+ alcohol use at
six months
22.2
20.3
23.3
22.0
Depressive Sxsa
81.1
81.1
80.2
80.8
Poor Emotional Well
73.3
65.8
62.8
67.5
Primarily Drug Users
7.8
12.7
17.4
12.6
Primarily Non Drug
51.1
45.6
48.8
48.6
Both
34.4
38.0
32.6
34.9
No One
6.7
3.8
1.2
3.9
Nyamathi et al.
> 180
MI-Single
Program
Psychological Resources
Beingb
Social Support From:
Users
+
recent refers to past month
++
a
denotes number of drinks consumed over the last 30 days
Based on a CES-D short form (10 items) score of 8 or more
b
Based on a score of 65 or less on a 0–100 scale
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Page 17
Table 2
Associations between Baseline Characteristics and Reduction of Alcohol Use by At Least 50%
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Characteristic
50% Reduction in Drinking
No
Yes
(N = 126)
(N = 124)
Background
Mean Age (SD)
51.5
Male
65.1
8.3
50.0
8.6
53.2
Ethnicity*
African American
39.7
51.6
White
18.3
18.6
Latino
29.4
24.2
Other
12.7
5.7
High School Grad
54.8
62.9
Employed
17.6
16.9
Beverly
24.8
14.1
Southeast
29.6
35.5
Lynwood
11.2
7.4
Recruitment Site:
NIH-PA Author Manuscript
Matrix
22.4
27.3
TriCity
12.0
15.7
Fair/poor health
55.4
61.8
Childhood Physical Abuse
20.6
28.2
Lifetime Traded Sex
31.8
41.5
Alcohol-Abusing
38.4
41.1
33.9
25.0
0–40
27.0
20.2
41–89
31.0
19.4
90–180
28.6
25.8
> 180
13.5
34.7
31.5
33.1
Partner
Drug-Abusing Partner
Quartiles for Baseline
Alcohol Use***
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Baseline ASI Drug High
Recent Marijuana use
19.8
11.3
Recent + IDU
43.7
35.5
Recent+ Self-help Prog
19.8
22.6
Smoke ≥1 pack/day
50.0
61.1
Multiple Sex Partners
20.6
16.9
Depressive Sxs
13.6 (6.3)
12.9 (6.0)
Emotional Well-Being
49.7 (24.1)
54.5 (21.5)
Psychosocial Resources
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Page 18
Characteristic
50% Reduction in Drinking
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No
Yes
(N = 126)
(N = 124)
Primary Drug User
14.3
5.7
Primary Non Drug
45.2
52.4
Both
37.3
33.1
No one
3.2
4.8
64.1
74.4
Social Support
User
Completed Vaccine
+
*
recent refers to past six-month period
p < .05, chi-square or t test
**
p < .01, chi-square or t test
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Page 19
Table 3
Logistic Regression Results for 50% Reduction of Alcohol Use (N = 249)
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Adjusted Odds Ratio
95% CI
P Value
Intervention Programs (vs HHP)
+
MI-Single
0.91
0.47, 1.73
.765
MI-Group
1.53
.76, 3.09
.231
Female
1.95
1.11, 3.44
.021
Education
1.16
1.00, 1.33
.045
Baseline Alcohol Use
1.68
1.30, 2.17
.001
Drug-Using Partner
0.56
0.30, 1.02
.058
Recent+ Marijuana Use
0.34
0.14, 0.80
.013
HBV Vaccination
1.84
1.06, 3.18
.013
recent refers to the past month
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Drug Alcohol Depend. Author manuscript; available in PMC 2012 June 26.