Testing the short-term effectiveness of primary care referral to online weight loss programmes: A randomised controlled trial.

Guidelines ask health professionals to offer brief advice to encourage weight loss for people living with obesity. We tested whether referral to one of three online programmes could lead to successful weight loss. A total of 528 participants aged ≥18 years with a body mass index of ≥30 kg/m2 were invited via a letter from their GP. Participants were randomised to one of three online weight loss programmes (NHS Weight Loss Plan, Rosemary Online or Slimming World Online) or to a control group receiving no intervention. Participants self-reported weight at baseline and 8 weeks. The primary outcome was weight change in each of the active intervention groups compared with control. We also compared the proportion of participants losing ≥5% or ≥10% of body weight. For Rosemary, Online mean weight loss was modestly greater than control (-1.5 kg [95% confidence interval (CI) -2.3 to -0.6]) and more than three times as many participants in this group lost ≥5% (relative risk [RR] = 3.64, 95% CI: 1.63-8.1). For Slimming World, mean weight loss was not significantly different from control (-0.8 kg [95%CI -1.7 to 0.1]), twice as many participants lost ≥5% (RR = 2.70, 1.17-6.23). There was no significant difference in weight loss for participants using the NHS Weight Loss Plan (-0.4 kg, [95% CI -1.3 to 0.5]), or the proportion losing ≥5% (RR = 2.09, 0.87-5.01). Only one of three online weight loss programmes was superior to no intervention and the effect size modest among participants living with obesity.

Extended follow-up of a short total diet replacement programme: results of the Doctor Referral of Overweight People to Low Energy total diet replacement Treatment (DROPLET) randomised controlled trial at 3 years.

OBJECTIVES: To test the long-term effectiveness of a total diet replacement programme (TDR) for routine treatment of obesity in a primary care setting. METHODS: This study was a pragmatic, two-arm, parallel-group, open-label, individually randomised controlled trial in adults with obesity. The outcomes were change in weight and biomarkers of diabetes and cardiovascular disease risk from baseline to 3 years, analysed as intention-to-treat with mixed effects models. INTERVENTIONS: The intervention was TDR for 8 weeks, followed by food-reintroduction over 4 weeks. Behavioural support was provided weekly for 8 weeks, bi-weekly for the next 4 weeks, then monthly for 3 months after which no further support was provided. The usual care (UC) group received dietary advice and behavioural support from a practice nurse for up to 3 months. RESULTS: Outcome measures were collected from 179 (66%) participants. Compared with baseline, at 3 years the TDR group lost -6.2 kg (SD 9.1) and usual care -2.7 kg (SD 7.7); adjusted mean difference -3.3 kg (95% CI: -5.2, -1.5), p < 0.0001. Regain from programme end (6 months) to 3 years was greater in TDR group +8.9 kg (SD 9.4) than UC + 1.2, (SD 9.1); adjusted mean difference +6.9 kg (95% CI 4.2, 9.5) P < 0.001. At 3 years TDR led to greater reductions than UC in diastolic blood pressure (mean difference -3.3 mmHg (95% CI:-6.2; -0.4) P = 0.024), and systolic blood pressure (mean differences -3.7 mmHg (95% CI: -7.4; 0.1) P = 0.057). There was no evidence of differences between groups in the change from baseline to 3 years HbA1c (-1.9 mmol/mol (95% CI: -0.7; 4.5; P = 0.15), LDL cholesterol concentrations (0.2 mmol/L (95% CI -0.3, 0.7) P = 0.39), cardiovascular risk score (QRISK2) (-0.37 (95% CI -0.96; 0.22); P = 0.22). CONCLUSIONS: Treatment of people with obesity with a TDR programme compared with support from a practice nurse leads to greater weight loss which persists to at least 3 years, but there was only evidence of sustained improvements in BP and not in other aspects of cardiometabolic risk.