Using motivational interviewing to enhance emerging adults' engagement in weight loss: The Live Well RVA pilot...

Emerging adults (ages 18-25) are at high risk for overweight/obesity, yet traditional adult behavioural weight loss (BWL) interventions do not meet the needs of individuals at this developmental stage. Motivational interviewing (MI) is an evidence-based approach to promote behaviour change but has not been tested for weight loss in this population. The study aimed to test the feasibility and preliminary efficacy of an MI-enhanced weight loss programme to promote engagement, retention and weight loss in emerging adults.

Emerging adults with overweight/obesity (N = 47, 81% female, 47% racial/ethnic minority, body mass index [BMI] = 33.2 ± 4.6 kg/m²) were randomized to either standard BWL or MI-enhanced BWL (MIBWL). Weight was assessed objectively at baseline and posttreatment (3 months). Engagement (in-person session attendance [weeks 1 and 2], online self-monitoring [weeks 3-12] and online content viewing [weeks 3-12]) was tracked throughout the program.

Though results did not reach the level of statistical significance, participants in MIBWL demonstrated greater programme engagement (77% vs. 61.0%, p = .11; Cohen d = .48), retention (71% vs. 48.0%, p = .10; Cohen h = .47) and intent-to-treat weight loss (-3.3% vs. -2.2%, p = .37; Cohen d = .26) compared with those in BWL.

Effect sizes suggest that MI might be a viable approach to enhance engagement and retention in weight loss programmes targeting emerging adults. This finding is meaningful, given the documented challenges with engagement and retention in this vulnerable population and the relationship between engagement and better weight loss outcomes. The results of this small pilot study support efforts to replicate these findings within the context of a fully powered trial.