Do weight loss outcomes and experiences differ for men with obesity and multiple long-term conditions or disability in the Games of Stones text message with or without financial incentive randomised controlled trial?

Problem

The prevalence of obesity and consequent morbidities are rising. Men engage less frequently with weight loss interventions than women and there is an evidence gap for those living with multiple long-term conditions (MLTC) or disability. Our pre-specified aims were to: undertake sub-group analyses to understand whether living with MLTC, a single co-morbidity or a disability moderates weight change outcomes; and triangulate results with qualitative interview data to understand experiences of men relevant to implementation.

Approach

Participants were 585 men with body mass index (BMI) > 30 kg/m2 recruited through General Practice and community strategies during the Covid-19 pandemic. Participants were randomly allocated to daily automated behavioural text messages; text messages with endowment financial incentives linked to 5% and 10% weight loss targets; or a year long waiting list control group. MLTC was defined as two or more self-reported obesity-related conditions; the Office for National Statistics standardised disability question was used. Secondary analysis compared percentage weight change at 12 months from baseline for each intervention group to the waiting list. The four baseline sub-groups were: MLTC; disability; single, no co-morbidity. Moderating effects were explored using linear regression models that included treatment-by-subgroup interactions, using 99.5% confidence intervals. Purposive and diversity sampling resulted in 54 qualitative interviews with men (texts with incentives n=30; texts only n=24) at 12 months: MLTC (n=18) and included men with disabilities (n=25). Analysis used the Framework method to compare data across trial groups and sub-groups.

Findings

At baseline, 235 (40%) reported MLTC; 140 (24%) no co-morbidities and 233 (40%) a physical or mental health disability. Mean percentage weight change from baseline (SD) was -4.8% (6.1) for texts with incentives, -2.7% (6.3) for texts only, and -1.3% (5.5) for waiting list. In the texts only group compared to waiting list, the mean difference in % weight at 12 months from baseline for men with MLTC was 0.4 (99.5% Confidence interval (CI) -3.8, 4.6. p=0.8). In the texts with incentives group compared to waiting list, the mean difference in % weight at 12 months from baseline for men with MLTC was 0.4 (99.5% CI, -3.7, 4.4. p=0.8). Similarly, all subgroup comparisons found no moderation of the primary weight loss outcome by the presence or absence of co-morbidities or disability. Of the 357 adverse events reported, the most common were infections (23%).Qualitative findings will be presented that illuminate the experiences of men living with obesity, MLTC and their weight loss trajectories. Health adverse events experienced by men regardless of trial group or long-term conditions can impact substantially on motivation and weight loss.

Consequences

The effectiveness and cost-effectiveness findings for Game of Stones interventions are generalisable for underserved men with long term obesity related co-morbidities or disability.