Using Motivational Interviewing as a Supplement to Obesity Treatment: A Stepped-Care Approach

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1 Health Psychology Copyright 2007 by the American Psychological Association 2007, Vol. 26, No. 3, /07/$12.00 DOI: / Using Motivational Interviewing as a Supplement to Obesity Treatment: A Stepped-Care Approach Robert A. Carels, Lynn Darby, Holly M. Cacciapaglia, Krista Konrad, Carissa Coit, Jessica Harper, Mary E. Kaplar, Kathleen Young, Chelsea A. Baylen, and Amelia Versland Bowling Green State University Objective: This investigation was designed to improve behavioral weight loss program (BWLP) treatment outcomes by providing stepped care (SC) to individuals experiencing difficulties with weight loss during treatment. SC entails transition to more intensive treatments when less intensive treatments fail to meet treatment goals. In a BWLP, motivational interviewing (MI) may increase participants motivation toward behavioral change and thus complement the acquisition of behavioral change skills. It was hypothesized that BWLP SC (MI) participants (i.e., participants who failed to meet weight loss goals and received MI) would demonstrate superior treatment outcomes when compared with BWLP (SC matched) participants (i.e., participants who failed to meet weight loss goals but did not receive MI). Design: Fifty-five obese, sedentary adults were randomly assigned to a BWLP SC or a BWLP. Main outcome measures: Changes in weight, cardiorespiratory fitness, self-reported physical activity, and diet (i.e., calories, percentage daily intake of fat, protein, and carbohydrates) in response to treatment were assessed. Results: Participants significantly decreased their weight, increased physical activity/fitness, and improved dietary intake ( ps.05). BWLP SC (MI) participants lost more weight and engaged in greater weekly exercise than BWLP (SC matched) participants who did not receive MI ( ps.05). Conclusion: For individuals experiencing weight loss difficulties during a BWLP, MI may have considerable promise. Keywords: obesity, stepped care, treatment, weight loss, motivational interviewing Effective management of the current obesity epidemic will likely require cost-effective, time-efficient, minimally intrusive treatments. In a stepped-care (SC) approach, patients are transitioned to more intensive treatments when less intensive treatments are insufficient, thereby reducing the likelihood that some patients will receive unnecessary treatment (Haaga, 2000). SC approaches have been developed for treatment of a variety of conditions, including weight management (Abrams, 1993; Carels et al., 2005; Expert Panel on Detection, 2001; National Heart, Lung, and Blood Institute [NHLBI], 1997; Sobell & Sobell, 2000; Wadden, Brownell, & Foster, 2002). A SC approach is consistent with the increased emphasis on individualizing treatment programs (e.g., Diabetes Prevention Program Research Group, 2002), because initiation of more intensive treatment is based on an individual s progress toward treatment goals. In addition, promptly intensifying treatment in response to poor progress may be necessary to prevent poor treatment outcome across a number of psychological and behavioral domains (e.g., Smith et al., 2001), including weight loss. Robert A. Carels, Holly M. Cacciapaglia, Krista Konrad, Carissa Coit, Jessica Harper, Mary E. Kaplar, Kathleen Young, Chelsea A. Baylen, and Amelia Versland, Psychology Department, Bowling Green State University; Lynn Darby, School of Human Movement, Sports, and Leisure Studies, Bowling Green State University. Correspondence concerning this article should be addressed to Robert A. Carels, Psychology Department, Bowling Green State University, 208 Psychology Building, Bowling Green, OH rcarels@ bgnet.bgsu.edu Research examining a SC approach to weight loss has been encouraging. In Carels et al. s (2005) study, eligible behavioral weight loss program (BWLP) participants received SC based on problemsolving therapy (D Zurilla, 1999). BWLP SC participants had superior weight loss compared with BWLP participants. However, it was anecdotally observed that some participants expressed considerable ambivalence toward making lifestyle changes, and it was speculated that participants might benefit from a technique that would enhance their motivation toward lifestyle modification. Motivational interviewing (MI) is a therapeutic technique designed to enhance an individual s motivation to change behaviors and move him or her into action (Miller & Rollnick, 2002). Although originally used to treat addictive behaviors, MI is now being used in several ongoing clinical trials to enhance health behaviors, including diet and exercise (Hecht et al., 2005). Evidence for the effectiveness of MI in enhancing dietary change and physical activity is limited (Burke, Arkowitz, & Menchola, 2003; Dunn, Deroo, & Rivara, 2001; Resnicow et al., 2005). In the current investigation, eligible participants were stepped up to more intensive treatment (i.e., MI) when poor progress toward weight loss goals was detected. We hypothesized that BWLP SC (MI) participants (i.e., BWLP SC participants who failed to meet weight loss goals and received MI) would demonstrate superior treatment outcomes when compared with BWLP (SC matched) participants (i.e., BWLP participants who failed to meet weight loss goals but did not receive MI). In Carels et al. s (2005) study, more BWLP SC participants achieved their minimum weight loss goals than BWLP participants. Therefore, we hypothesized that compared with BWLP participants, BWLP 369

2 370 BRIEF REPORTS SC participants would be more likely to achieve weight loss goals and have superior treatment outcomes. Participants Method Fifty five obese, sedentary adults were recruited through advertisements in local newspapers and campus at a Midwestern university (see Table 1). Participants were included if they were (a) obese (body mass index [BMI] 30 kg/m 2 ), (b) sedentary (exercise 2 times per week), and (c) nonsmokers; they were excluded if they had (a) cardiovascular disease, (b) musculoskeletal problems preventing moderate physical activity, or (c) insulindependent diabetes or impaired fasting glucose ( 110 mg/dl). All participants received their physician s medical clearance. Study Design A project coordinator randomly assigned (using computerized random number generator) participants to the BWLP (n 27) or BWLP SC (n 28) group following enrollment but prior to the beginning of treatment. Forty-six (22 BWLP; 24 BWLP SC) participants completed the investigation (see Figure 1 for participant flow diagram). Guided by published estimates of average weight loss in BWLPs (Wing, 2002), we gave all participants minimum (10%), moderate (14%), and ambitious (18%) end-oftreatment weight loss goals. BWLP participants were not eligible to receive MI. MI was provided to participants in the BWLP SC condition only if they failed to meet weight loss goals. Participants received SC if they did not meet the following percentage of total body weight loss goals: (a) 1.25% by Week 3, (b) 1.25% between the 3 rd and 6 th week, (c) 2.5% between the 6 th and 12 th week, or (d) 2.5% between the 12 th and 18 th week. Participants were not required to make-up weight loss from prior unsuccessful assessments. They continued to attend their weight loss groups while in SC. Sixteen BWLP SC (i.e., BWLP SC [MI]) and 19 BWLP (i.e., BWLP [SC matched]) participants failed to meet treatment goals. Pre-post Table 1 Demographic Characteristics Demographics BWLP SC a BWLP b Total c n % n % n % Gender (women) Race (Caucasian) Income $30, College degree Married Occupation d Not currently working Nonmanual clerical Nonmanual professional Note. BWLP behavioral weight loss program; SC stepped care. a Mean age 48.3 years (SD 11.0; range 24 55). b Mean age 48.0 years (SD 9.0; range 31 61). c Mean age 48.2 years (SD 10.0; range 24 65). d Missing data for 11 participants. assessments of weight, cardiorespiratory fitness, and nutrition were completed. Interventions Weight loss program. The 20-session BWLP was 24 weeks in duration (including holidays) and was based on the LEARN program (Brownell, 2000). The BWLP was administered in 75-min weekly sessions in groups of 6-12 participants. The LEARN program emphasizes gradual weight loss, progressively increasing physical activity, and decreasing energy and fat intake through permanent lifestyle changes. Information on LEARN can be found at MI. Eligible SC participants received MI (Miller & Rollnick, 2002). MI is a goal-directed method designed to decrease ambivalence toward behavior change. Eligible participants met weekly with a clinical psychology doctoral student for min individual sessions. MI was discontinued when participants met their weight loss goal in a following assessment period unless continuation was requested by the participant. Therapist training included 20 hr of readings (Miller & Rollnick, 2002), video (Miller, Rollnick, & Moyers, 1998), role play, and discussions of MI principles and strategies. Treatment integrity. Out of 102 therapy sessions, 25 were randomly selected for treatment integrity coding. Random 20-min segments of tape were evaluated by two clinical psychology doctoral students (nontherapists) who received 40 hr of training with the Motivational Interviewing Treatment Integrity Code (MITI; Moyers, Martin, Manuel, Hendrickson, & Miller, 2005; Moyers, Martin, Manuel, & Miller, 2003). MITI behavior counts were used to code for general therapist behaviors: information giving (IG), close (CQ)/open-ended (OQ) questions, simple (SR)/complex (CR) reflections, MI adherent behaviors (MIA), and MI nonadherent behaviors (MINA). We averaged global scores (GS) for global empathy and MI spirit (both of which were on a 7-point scale). We estimated interrater reliability using the intraclass correlation (ICC). ICCs were.92 for Spirit,.78 for Empathy/ Understanding, and exceeded.95 for each of the behavioral counts (i.e., IG, CQ, OQ, CR, SR, MIA, MINA). Means for the behavioral counts were as follows: IG 2.8 (SD 3.0), CQ 8.4 (SD 6.0), OQ 4.7 (SD 4.0), CR 5.2 (SD 2.7), SR 11.9 (SD 6.6), MIA 10.2 (SD 7.1), and MINA 1.6 (SD 2.3). MI proficiency guidelines (Moyers et al., 2003) suggest that the following criteria are indicative of MI competence: (a) GS 5, (b) % OQ.50, (c) % CR.40, (d) % MIA.90, and (e) ratio of reflections to questions 1. In this investigation, GS (M 5.3, SD 1.1) and the reflection to questions ratio (M 1.3) were above proficiency, whereas % OQ (M 0.35, SD 0.23), % CR (M 0.35, SD 0.23), and % MIA (M 0.90; SD 0.16) were slightly below proficiency. Treatment Outcome Measures Cardiorespiratory fitness and physical activity logs. To determine VO 2 max, we had each participant complete a submaximal graded exercise test (American College of Sports Medicine, 2000) using the modified Balke treadmill-walking protocol. VO 2 max was predicted from the regression equation for the relationship between submaximal VO 2 and heart rate at one or more submaxi-

3 BRIEF REPORTS 371 Assessed: 166 Eligible: 100 Decline: 45 Total Sample N = 55 BWLP Not Eligible to Receive MI/ N = 27 BWLP + SC N = 28 mal work loads (American College of Sports Medicine, 2000). Participants also recorded the type and duration of daily planned physical activity in a daily activity diary. Average minutes per week of time spent in planned physical activity were computed from the diary. Forty-five participants completed a physical activity diary, and 37 completed fitness testing. Body weight. Body weight was measured using a digital scale (BF-350e; Tanita, Arlington Heights, IL) to the closest 0.1 lb., and height was measured in inches to the closest 0.5 inch using a height rod on a standard spring scale. Dietary assessment. Participants recorded food intake over 4 days (2 weekdays, 2 weekend days) at baseline and posttreatment. Estimates for total calories, calories from fat, carbohydrates, and protein were derived using Nutribase, 2001 Professional Nutrition software (Phoenix, AZ). Ten participants failed to complete dietary assessments. Data Analysis Drop out N = 5 BWLP (SC matched) Failed to meet WL Goals / Did not receive MI N = 16 Completers N = 22 Met WL goals N = 6 Baseline differences between treatment groups were assessed with one-way ANOVA and chi-square analyses. Chi-square analyses were used to compare BWLP with BWLP SC participants who achieved their minimum weight loss goals during the five assessments. To demonstrate intervention effectiveness as a precursor to making between-group comparisons, we evaluated pre- and posttreatment effects using two-way repeated-measures ANOVA. Treatment group was the between-group factor. All analyses were repeated for BWLP SC (MI) versus BWLP (SC matched). An intent-to-treat approach was used for all analyses. Because the BWLP SC was hypothesized a priori to have superior treatment outcomes when compared with the BWLP, we used one-tailed significance tests ( p.05). Drop out N = 4 BWLP + SC (MI) Failed to meet WL Goals / Received MI N = 19 Completers N = 24 Met WL goals N = 5 Figure 1. Participant flow diagram. Recruitment was from August 2004 to October Treatment was from October 2004 to April BWLP behavioral weight loss program; SC stepped care; MI motivational interviewing; WL weight loss. Results Baseline Characteristics and MI Eligibility There were no significant differences between the groups on baseline demographics (see Table 1), weight (see Table 2), medication, alcohol use (see Table 3) or attrition. The groups did not differ in the number of participants who were eligible for SC (16 BWLP participants; 19 BWLP SC). Participants who were eligible for SC attended an average of 5.4 MI sessions (SD 4.3; range 1 15). Comparison Between BWLP SC (MI) and BWLP (SC Matched) Groups Among the BWLP SC (MI; n 19) and BWLP (SC matched; n 16) groups, there were significant pre to post decreases in body weight (M 3.4 kg, SD 3.1), F(1, 33) 43.52, p.01; daily caloric intake (M 382, SD 452), F(1, 29) 21.53, p.01; and percentage daily energy from fat (M 2.9, SD 6.8), F(1, 29) 4.66, p.05; in addition, there were significant increases in VO 2 max (M 1.9 ml/ kg 1 *min 1, SD 3.6), F(1, 22) 6.66, p.01, and percentage daily calories from protein (M 1.8, SD 4.0), F(1, 29) 6.15, p.01. BWLP SC (MI) participants lost more weight compared with BWLP (SC matched) participants, F(1, 33) 5.85, p.05 (see Table 4). Compared with BWLP (SC matched) participants, BWLP SC (MI) participants engaged in an additional 68 min per week of planned physical activity (M 218, SD 96 vs. M 150, SD 133), F(1, 31) 2.76, p.05, Cohen s d.60.

4 372 BRIEF REPORTS Table 2 Behavioral Weight Loss Program (BWLP) With Stepped Care (SC) Versus BWLP on Treatment Outcomes BWLP with SC (n 24) BWLP (n 22) Effect size Cohen s d Pre Post Difference Pre Post Difference M SD M SD M SD M SD M SD M SD WG BG Participants Body weight and fat weight (kg) * 0.39 Physical fitness VO 2 max (ml/kg 1 min 1 ) * 0.02 Nutrition Total calories 2, , , , * 0.01 % carbohydrates % protein * 0.11 % fat * 0.24 Note. WG within group; BG between group. * p.05 (pre- vs. posttreatment). Table 3 Medication and Alcohol Use Variable BWLP SC BWLP Total Comparison Between BWLP and BWLP SC Total Groups When all BWLP (n 22) and BWLP SC (n 24) participants were compared, there were significant pre to posttreatment decreases in body weight (M 4.8 kg, SD 5.3), F(1, 53) 45.3, p.01; daily caloric intake (M 277, SD 427), F(1, 48) 20.71, p.01; and percentage daily energy from fat (M 2.9, SD 6.5), F(1, 48) 8.77, p.01; in addition, there were significant increases in VO 2 max (M 3.8 ml/kg 1 *min 1, SD 4.8), F(1, 33) 21.26, p.01, and percentage daily calories from protein (M 1.1, SD 3.6), F(1, 48) 3.42, p.05 (see Table 2). There was no significant difference in weight loss between the BWLP SC and BWLP groups, F(1, 53) 2.0, p.08 (see Table 2). Compared with BWLP participants, BWLP SC participants engaged in an additional 58 min per week of planned physical activity (M 216, SD 96 vs. M 158, SD 116), F(1, 44) 3.28, p.05, Cohen s d.55. No group differences were observed in dietary intake or VO 2 max. Discussion n % n % n % Medication Thyroid Cardiac Anti-depressant Hormone replacement therapy Alcohol use None per day per day per day Note. BWLP behavioral weight loss program; SC stepped care. Consistent with prior SC research (Carels et al., 2005), BWLP SC (MI) participants lost significantly more weight and engaged in significantly greater physical activity than BWLP (SC matched) participants. The effect sizes for exercise (Cohen s d 0.60) and weight loss (Cohen s d 0.84) in this investigation were higher but consistent with prior research using MI to increase physical activity (Cohen s ds from ) and reduce body weight (Cohen s ds from ; Dunn et al., 2001; Burke et al., 2003). When comparing all BWLP and BWLP SC participants, BWLP SC participants engaged in significantly greater physical activity each week. It is important to note that at some point during treatment, nearly two thirds of participants (n 35) failed to meet their minimum weight loss goals. In contrast to previous findings (Carels et al., 2005), compared with BWLP participants, BWLP SC participants were not more likely to achieve their weight loss goals. The final weight loss goal of 10% total body weight in this investigation was more stringent than the 8% weight loss goal in Carels et al. s (2005) study and may account for this discrepancy.

5 BRIEF REPORTS 373 Table 4 Behavioral Weight Loss Program (BWLP) With Stepped Care (SC) Participants Who Received Motivational Interviewing (MI) Versus BWLP Participants Matched on SC Eligibility on Treatment Outcomes BWLP with SC (MI) (n 19) BWLP (SC matched) (n 16) Effect size Cohen s d Pre Post Difference Pre Post Difference M SD M SD M SD M SD M SD M SD WG BG Participants Body weight (kg) * 0.84* Physical fitness VO 2 max (ml/kg 1 min 1 ) * 0.12 Nutrition Total calories 2, , , , * 0.11 % carbohydrates % protein * 0.04 % fat * 0.15 Note. WG within group; BG between group. * p.05 (for WG, pre- vs. posttreatment; for BG, BWLP SC vs. BWLP). The better treatment outcomes in the BWLP SC (MI) participants were at least partly attributable to the superior performance of the participants receiving MI. For individuals who are having difficulties losing weight, MI may increase intrinsic motivation for change, thus resulting in more positive behavior change. For example, BWLP SC (MI) participants exercised an additional 68 min per week compared with BWLP (SC matched) participants. Despite the favorable treatment outcomes for SC participants, these conclusions should be viewed tentatively. Replication with a larger, more diverse sample is warranted. It is unclear whether the observed benefits in those who received SC were due to MI or simply additional therapeutic contact. Future research would benefit from a comparison of MI to a nondirective therapeutic contact condition or an alternative treatment approach. Finally, although MI therapy was delivered in a competent manner, performance was slightly below established criteria on three MI proficiency indices. Although this performance could limit the dose effectiveness of the MI therapy (Bellg et al., 2004), participants who received MI lost significantly more weight and exercised significantly more than comparable BWLP participants. Cost-effective, uniquely tailored treatments are needed to effectively manage the obesity epidemic (Haaga, 2000; NHLBI Obesity Education Initiative Task Force Members, 1998; Sobell & Sobell, 2000). Although the promising results from the current investigation suggest that the application of SC principles to the treatment of obesity may have considerable merit, further examination of this approach is clearly warranted References Abrams, D. B. (1993). Treatment issues in tobacco dependence: Towards a stepped-care model. Tobacco Control, 2, S17 S37. American College of Sports Medicine. (2000). ACSM s guidelines for exercise testing and prescription. Baltimore: Williams & Wilkins. Bellg, A. J., Borrelli, B., Resnick, B., Hecht, J., Minicucci, D. S., Ory, M., et al. (2004). Enhancing treatment fidelity in health behavior change studies: Best practices and recommendations from the NIH Behavior Change Consortium. Health Psychology, 23, Brownell, K. D. (2000). The LEARN program for weight management Dallas, TX: American Health. Burke, B. L., Arkowitz, H., & Menchola, M. (2003). The efficacy of motivational interviewing: A meta-analysis of controlled clinical trials. Journal of Consulting and Clinical Psychology, 71, Carels, R. A., Darby, L. A., Cacciapaglia, H. M., Douglass, O. M., Harper, J., Kaplar, M., et al. (2005). Applying a stepped care approach to the treatment of obesity. Journal of Psychosomatic Research, 59, Diabetes Prevention Program Research Group. (2002). Reduction in the incidence of Type 2 diabetes with lifestyle intervention or metformin. New England Journal of Medicine, 346, Dunn, C., Deroo, L., & Rivara, F. P. (2001). The use of brief interventions adapted from motivational interviewing across behavioral domains: A systematic review. Addiction, 96, D Zurilla, T. J. (1999). Problem-solving therapy: A social competence approach to clinical intervention. New York: Springer. Expert Panel on Detection. (2001). Executive summary of the third report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Pressure in Adults. Journal of the American Medical Association, 285, Haaga, D. A. (2000). Introduction to the special section on stepped care models in psychotherapy. Journal of Consulting and Clinical Psychology, 68, Hecht, J., Borrelli, B., Breger, R. K. R., DeFrancesco, C., Ernst, D., &

6 374 BRIEF REPORTS Resnicow, K. (2005). Motivational interviewing in community-based research: Experience from the field. Annals of Behavioral Medicine, 29, Miller, W. R., & Rollnick, S. (2002). Motivational interviewing: Preparing people for change (2nd ed.). New York: Guilford. Miller, W. R., Rollnick, S., & Moyers, T. B. (1998). Motivational interviewing professional training videotape series [Motion picture]. New Mexico: University of New Mexico, Center on Alcohol, Substance Abuse, and Addictions. Moyers, T. B., Martin, T., Manuel, J. K., Hendrickson, S. M. L., & Miller, W. R. (2005). Assessing competence in the use of motivational interviewing. Journal of Substance Abuse Treatment, 28, Moyers, T. B., Martin, T., Manuel, J. K., & Miller, W. R. (2003). The Motivational Interviewing Treatment Integrity (MITI) Code Version 2.0. Retrieved August 17, 2006, from miti.pdf National Heart, Lung, and Blood Institute. (1997). The sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (Report No ). Washington, DC: National Institutes of Health. National Heart, Lung, and Blood Institute Obesity Education Initiative ORDER FORM Start my 2007 subscription to Health Psychology! ISSN: $61.00, APA MEMBER/AFFILIATE $101.00, INDIVIDUAL NONMEMBER $379.00, INSTITUTION In DC add 5.75% / In MD add 5% sales tax TOTAL AMOUNT ENCLOSED $ Subscription orders must be prepaid. (Subscriptions are on a calendar year basis only.) Allow 4-6 weeks for delivery of the first issue. Call for international subscription rates. SEND THIS ORDER FORM TO: American Psychological Association Subscriptions 750 First Street, NE Washington, DC Or call , fax TDD/TTY For subscription information, subscriptions@apa.org Task Force Members. (1998). Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults: The evidence report (NIH Publication No ). Washington, DC: U.S. Department of Health and Human Services. Resnicow, K., Jackson, A., Blissett, D., Wang, T., McCarty, F., Rahotep, S., et al. (2005). Results of the Healthy Body Healthy Spirit Trial. Health Psychology, 24, Smith, S. S., Jorenby, D. E., Fiore, M. C., Anderson, J. E., Mielke, M. M., Beach, K. E., et al. (2001). Strike while the iron is hot: Can stepped care treatments resurrect relapsing smokers? Journal of Consulting and Clinical Psychology, 69, Sobell, M. B., & Sobell, L. C. (2000). Stepped care as a heuristic approach to the treatment of alcohol problems. Journal of Consulting and Clinical Psychology, 68, Wadden, T. A., Brownell, K. D., & Foster, G. (2002). Obesity: Managing the global epidemic. Journal of Consulting and Clinical Psychology, 70, Wing, R. R. (2002). Behavioral weight control. In T. Wadden & A. Stunkard (Eds.), Handbook of obesity treatment (2nd ed., pp ). New York: Guilford Press. Check enclosed (make payable to APA) Charge my: VISA MasterCard American Express Cardholder Name Card No. Exp. Date Signature (Required for Charge) BILLING ADDRESS: Street City State Zip Daytime Phone MAIL TO: Name Address City State Zip APA Member # HEAA17