The impact of the interventionist–participant relationship on treatment adherence and weight loss

• Published in: Translational behavioral medicine 2019-03, Vol.9 (2), p.368-372
• Main Authors: Krukowski, Rebecca A, West, Delia Smith, Priest, Jeffrey, Ashikaga, Takamaru, Naud, Shelly, Harvey, Jean R
• Format: Article
• Language: English
• Subjects: Accounting departments; Bonds (Securities); Diaries; Health aspects; Intervention (Psychology); Mediation; Original Research; Patient compliance; Patient outcomes; Practice; Psychological aspects; Psychotherapists; Social aspects; Therapist-patient relations; Weight loss
• ISSN: 1869-6716; 1613-9860
• DOI: 10.1093/tbm/iby007

Little is known about the impact of the relationship built between interventionists and their participants on weight loss. Our objective is to determine whether stronger early (i.e., 4 weeks) participant-interventionist bond is associated with significantly greater weight loss success and treatment adherence. Three hundred and ninety-eight participants received an online group behavioral weight control program over 18 months. Weight was measured objectively at baseline and at 6 and 18 months. At 4 weeks, participants completed the Working Alliance Inventory (WAI) bonding subscale, which measures the collaborative bond with the interventionist. Adherence (i.e., session attendance and online self-monitoring diary completion) was recorded by the interventionists. Participant-interventionist bond at 4 weeks was significantly associated with weight loss at 6 months (t(322) = -2.14, p = .03) but not at 18 months (t(290) = 0.53, p = .60). The model indicated that participant-interventionist bond at 4 weeks was a significant predictor of adherence at 6 months (b = .063, standard error [SE] = .30, p = .04), and 6 month adherence was a significant predictor of weight loss at 6 months (b = -.594, SE = .049, p < .0001). The indirect effect of the WAI-Bond subscale was significant (b = -.037, p = .03, 95% confidence interval: -.074, -.002) and accounted for 54% of the total effect of participant-interventionist bond on weight loss. However, the total weight loss explained by WAI-Bond subscale was small (0.04 kg). Participant-interventionist bond between participant and interventionist is an early predictor of treatment adherence and weight loss success at 6 months; however, the degree of weight loss explained by participant-interventionist bond is small and was not maintained at 18 months. Keywords Obesity, Weight loss, Interventionist, Alliance, Adherence