Randomised controlled trial and economic analysis of an internet-based weight management programme: POWeR+ (Positive Online Weight Reduction)

Abstract

BackgroundBehavioural counselling with intensive follow-up for obesity is effective, but in resource-constrained primary care settings briefer approaches are needed.ObjectivesTo estimate the clinical effectiveness and cost-effectiveness of an internet-based behavioural intervention with regular face-to-face or remote support in primary care, compared with brief advice.DesignIndividually randomised three-arm parallel trial with health economic evaluation and nested qualitative interviews.SettingPrimary care general practices in the UK.ParticipantsPatients with a body mass index of ≥ 30 kg/m2(or ≥ 28 kg/m2with risk factors) identified from general practice records, recruited by postal invitation.InterventionsPositive Online Weight Reduction (POWeR+) is a 24-session, web-based weight management intervention completed over 6 months. Following online registration, the website randomly allocated participants using computer-generated random numbers to (1) the control intervention (n = 279), which had previously been demonstrated to be clinically effective (brief web-based information that minimised pressure to cut down foods, instead encouraging swaps to healthier choices and increasing fruit and vegetables, plus 6-monthly nurse weighing); (2) POWeR+F (n = 269), POWeR+ supplemented by face-to-face nurse support (up to seven contacts); or (3) POWeR+R (n = 270), POWeR+ supplemented by remote nurse support (up to five e-mails or brief telephone calls).Main outcome measuresThe primary outcome was a modelled estimate of average weight reduction over 12 months, assessed blind to group where possible, using multiple imputation for missing data. The secondary outcome was the number of participants maintaining a 5% weight reduction at 12 months.ResultsA total of 818 eligible individuals were randomised using computer-generated random numbers. Weight change, averaged over 12 months, was documented in 666 out of 818 participants (81%; control,n = 227; POWeR+F,n = 221; POWeR+R,n = 218). The control group maintained nearly 3 kg of weight loss per person (mean weight per person: baseline, 104.4 kg; 6 months, 101.9 kg; 12 months, 101.7 kg). Compared with the control group, the estimated additional weight reduction with POWeR+F was 1.5 kg [95% confidence interval (CI) 0.6 to 2.4 kg;p = 0.001] and with POWeR+R was 1.3 kg (95% CI 0.34 to 2.2 kg;p = 0.007). By 12 months the mean weight loss was not statistically significantly different between groups, but 20.8% of control participants, 29.2% of POWeR+F participants (risk ratio 1.56, 95% CI 0.96 to 2.51;p = 0.070) and 32.4% of POWeR+R participants (risk ratio 1.82, 95% CI 1.31 to 2.74;p = 0.004) maintained a clinically significant 5% weight reduction. The POWeR+R group had fewer individuals who reported doing another activity to help lose weight [control, 47.1% (64/136); POWeR+F, 37.2% (51/137); POWeR+R, 26.7% (40/150)]. The incremental cost to the health service per kilogram weight lost, compared with the control group, was £18 (95% CI –£129 to £195) for POWeR+F and –£25 (95% CI –£268 to £157) for POWeR+R. The probability of being cost-effective at a threshold of £100 per kilogram was 88% and 98% for POWeR+F and POWeR+R, respectively. POWeR+R was dominant compared with the control group. No harms were reported and participants using POWeR+ felt more enabled in managing their weight. The qualitative studies documented that POWeR+ was viewed positively by patients and that health-care professionals generally enjoyed supporting patients using POWeR+.Study limitationsMaintenance of weight loss after 1 year is unknown.Future workIdentifying strategies for longer-term engagement, impact in community settings and increasing physical activity.ConclusionClinically valuable weight loss (> 5%) is maintained in 20% of individuals using novel written materials with brief follow-up. A web-based behavioural programme and brief support results in greater mean weight loss and 10% more participants maintain valuable weight loss; it achieves greater enablement and fewer participants undertaking other weight-loss activities; and it is likely to be cost-effective.Trial registrationCurrent Controlled Trials ISRCTN21244703.FundingThis project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full inHealth Technology Assessment; Vol. 21, No. 4. See the NIHR Journals Library website for further project information.

Relationships of maternal body mass index and plasma biomarkers with childhood body mass index and adiposity at 6 years: The Children of SCOPE study

“…26 Previous studies have also shown that weight management programmes in adults have successfully shown a reduction of 1 kg/m 2 in BMI. Our study suggests that if this was to be achieved in women with overweight or obesity prior to pregnancy , 27 this would reduce the risk of increased infant adiposity. It is therefore plausible that the effect sizes found are meaningful at a population level.…”

Acceptability and feasibility of weight management programmes for adults with severe obesity: a qualitative systematic review

“…Four additional papers were identified from included RCTs. In all, 33 papers met our inclusion criteria 17–49…”

“…Although no included papers provided qualitative data from those who had been invited to join a programme, but had declined to take part at recruitment stage, some papers reported including participants who had not fully engaged with programme activities (being described as ‘low users’; ‘quitters’ or ‘drop outs’) 17 24 25 36…”

“…Two involved more remote forms of support (eg, email, telephone, text contact) 41 46. Other studies included and evaluated a mix of formats that also varied in intensity 17 19 23 25 30 36 37 42–44 48 49…”

“…Programmes incorporated a variety of tools and theories designed to support behaviour change and to help people lose weight. For example, tools such as diet diaries;24 37 workbooks;42–44 pedometers;36 37 48 food logs;17 47 conversation maps;22 interactive monitoring devices;46 social media group interaction;19 daily text messages;41 buddying 37. They also included a range of behaviour change theories (BCTs) and/or psychological support 20 21 26.…”