Cost-effectiveness of bariatric surgery and non-surgical weight management programmes for adults with severe obesity: a decision analysis model.

OBJECTIVES: To determine the most cost-effective weight management programmes (WMPs) for adults, in England with severe obesity (BMI ≥ 35 kg/m2), who are more at risk of obesity related diseases. METHODS: An economic evaluation of five different WMPs: 1) low intensity (WMP1); 2) very low calorie diets (VLCD) added to WMP1; 3) moderate intensity (WMP2); 4) high intensity (Look AHEAD); and 5) Roux-en-Y gastric bypass (RYGB) surgery, all compared to a baseline scenario representing no WMP. We also compare a VLCD added to WMP1 vs. WMP1 alone. A microsimulation decision analysis model was used to extrapolate the impact of changes in BMI, obtained from a systematic review and meta-analysis of randomised controlled trials (RCTs) of WMPs and bariatric surgery, on long-term risks of obesity related disease, costs, quality adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs) measured as incremental cost per QALY gained over a 30-year time horizon from a UK National Health Service (NHS) perspective. Sensitivity analyses explored the impact of long-term weight regain assumptions on results. RESULTS: RYGB was the most costly intervention but also generated the lowest incidence of obesity related disease and hence the highest QALY gains. Base case ICERs for WMP1, a VLCD added to WMP1, WMP2, Look AHEAD, and RYGB compared to no WMP were £557, £6628, £1540, £23,725 and £10,126 per QALY gained respectively. Adding a VLCD to WMP1 generated an ICER of over £121,000 per QALY compared to WMP1 alone. Sensitivity analysis found that all ICERs were sensitive to the modelled base case, five year post intervention cessation, weight regain assumption. CONCLUSIONS: RYGB surgery was the most effective and cost-effective use of scarce NHS funding resources. However, where fixed healthcare budgets or patient preferences exclude surgery as an option, a standard 12 week behavioural WMP (WMP1) was the next most cost-effective intervention.

A systematic review of UK-based long-term nonsurgical interventions for people with severe obesity (BMI ≥35 kg m-2 ).

INTRODUCTION: The aim of this project was to systematically review UK evidence on the effectiveness of long-term (≥12 months) weight management services (WMSs) for weight loss and weight maintenance for adults (≥16 years) with severe obesity (body mass index ≥35 kg m-2 ), who would generally be eligible for Tier 3 services. METHODS: Four data sources were searched from 1999 to October 2018. RESULTS: Our searches identified 20 studies, mostly noncomparative studies: 10 primary care interventions, nine in secondary care specialist weight management clinics and one commercial setting intervention. A programme including a phase of low energy formula diet (810-833 kcal day-1 ) showed the largest mean (SD) weight change at 12 months of -12.4 (11.4) kg for complete cases, with 25.3% dropout. Limitations or differences in evaluation and reporting (particularly for denominators), unclear dropout rates, and differences between participant groups in terms of comorbidities and psychological characteristics, made comparisons between WMSs and inferences challenging. CONCLUSIONS: There is a persistent and clear need for guidance on long-term weight data collection and reporting methods to allow comparisons across studies and services for participants with severe obesity. Data could also include quality of life, clinical outcomes, adverse events, costs and economic outcomes. A randomised trial comparison of National Health Service Tier 3 services with commercial WMSs would be of value.

Long term maintenance of weight loss with non-surgical interventions in obese adults: systematic review and meta-analyses of randomised controlled trials.

OBJECTIVE: To systematically review and describe currently available approaches to supporting maintenance of weight loss in obese adults and to assess the evidence for the effectiveness of these interventions. DESIGN: Systematic review with meta-analysis. DATA SOURCES: Medline, PsycINFO, Embase, and the Cochrane Central Register of Controlled Trials. STUDY SELECTION: Studies were identified through to January 2014. Randomised trials of interventions to maintain weight loss provided to initially obese adults (aged ≥ 18) after weight loss of ≥ 5% body weight with long term (≥ 12 months) follow-up of weight change (main outcome) were included. STUDY APPRAISAL AND SYNTHESIS: Potential studies were screened independently and in duplicate; study characteristics and outcomes were extracted. Meta-analyses were conducted to estimate the effects of interventions on weight loss maintenance with the inverse variance method and a random effects model. Results are presented as mean differences in weight change, with 95% confidence intervals. RESULTS: 45 trials involving 7788 individuals were included. Behavioural interventions focusing on both food intake and physical activity resulted in an average difference of -1.56 kg (95% confidence interval -2.27 to -0.86 kg; 25 comparisons, 2949 participants) in weight regain compared with controls at 12 months. Orlistat combined with behavioural interventions resulted in a -1.80 kg (-2.54 to -1.06; eight comparisons, 1738 participants) difference compared with placebo at 12 months. All orlistat studies reported higher frequencies of adverse gastrointestinal events in the experimental compared with placebo control groups. A dose-response relation for orlistat treatment was found, with 120 mg doses three times a day leading to greater weight loss maintenance (-2.34 kg, -3.03 to -1.65) compared with 60 mg and 30 mg three times a day (-0.70 kg, 95% confidence interval -1.92 to 0.52), P=0.02. CONCLUSIONS: Behavioural interventions that deal with both diet and physical activity show small but significant benefits on weight loss maintenance.

Lightening the load? A systematic review of community pharmacy-based weight management interventions.

The extent to which community pharmacies can increase capacity for weight management is unknown. Thus, the objective of the present paper was to evaluate the effectiveness and cost-effectiveness of community pharmacy weight management interventions. This paper used a design of systematic review and narrative synthesis. Electronic databases (1999-2009) were searched, including Medline, EMBASE, CINAHL and Pharm-line. Weight management studies in community pharmacies were eligible for the inclusion criteria. All languages and study designs were considered. Outcome measures included body weight or anthropometry (at baseline and at least one follow-up time point). Data were extracted through independent, duplicate data extraction and quality assessment. As a result, 10 studies were included, totalling 2,583 service users and 582 pharmacies from the USA, the UK, Switzerland, Spain and Denmark. One was a randomized controlled trial of a meal-replacement versus a reduced calorie diet. A non-randomized controlled before and after study compared community pharmacist treatment using Orlistat with usual care. Eight studies were uncontrolled. Five studies described behaviour change techniques. Long-term (12 months) mean weight loss measured in three studies ranged from 1.1 to 4.1 kg. Four uncontrolled studies reported statistically significant weight loss. No study reported economic evaluations. Currently, there is insufficient evidence for the effectiveness and cost-effectiveness of community pharmacy-based weight management initiatives to support investment in their provision.

Cardiovascular effects of calcium supplementation.

Trials in normal older women and in patients with renal impairment suggest that calcium supplements increase the risk of cardiovascular disease. To further assess their safety, we recently conducted a meta-analysis of trials of calcium supplements, and found a 27-31% increase in risk of myocardial infarction and a 12-20% increase in risk of stroke. These findings are robust because they are based on pre-specified analyses of randomized, placebo-controlled trials and show consistent risk across the trials. The fact that cardiovascular events were not primary endpoints of any of these studies will introduce noise but not bias into the data. A recent re-analysis of the Women's Health Initiative suggests that co-administration of vitamin D with calcium does not lessen these adverse effects. The increased cardiovascular risk with calcium supplements is consistent with epidemiological data relating higher circulating calcium concentrations to cardiovascular disease in normal populations. There are several possible pathophysiological mechanisms for these effects, including effects on vascular calcification, on the function of vascular cells, and on blood coagulation. Calcium-sensing receptors might mediate some of these effects. Because calcium supplements produce small reductions in fracture risk and a small increase in cardiovascular risk, there may be no net benefit from their use. Food sources of calcium appear to produce similar benefits on bone density, although their effects on fracture are unclear. Since food sources have not been associated with adverse cardiovascular effects, they may be preferable. Available evidence suggests that other osteoporosis treatments are still effective without calcium co-administration.

A qualitative study comparing commercial and health service weight loss groups, classes and clubs.

BACKGROUND: Group-based interventions for weight loss are popular; however, little is known about how health service groups compare with the commercial sector, from either the participant or the group leader perspective. Currently, health professionals have little guidance on how to deliver effective group interventions. The present study aimed to compare and contrast leaders' and attendees' experiences of health service and commercial weight loss groups, through in-depth interviews and group observations. METHODS: Purposive sampling, guided by a sampling frame, was employed to identify diverse groups operating in Scotland with differing content, structures and style. Data collection and analysis took place concurrently in accordance with a grounded theory approach. Thirteen semi-structured group observations and in-depth audio-recorded interviews with 11 leaders and 22 attendees were conducted. Identification of themes and the construction of matrices to identify data patterns were guided by the Framework Method for qualitative analysis. RESULTS: Compared to commercial groups, health service 'groups' or 'classes' tended to offer smaller periodic fixed term groups, involving gatekeeper referral systems. Commercial organisations provide a fixed branded package, for 'club' or 'class' members, and most commercial leaders share personal experiences of losing weight. Health service leaders had less opportunity for supervision, peer support or specific training in how to run their groups compared to commercial leaders. CONCLUSIONS: Commercial and health service groups differ in access; attendee and leader autonomy; engagement in group processes; and approaches to leadership and training, which could influence weight loss outcomes. Health service groups can provide different group content and experiences, particularly for those with chronic diseases and for populations less likely to attend commercial groups, such as men.

Factors influencing the participation of older people in clinical trials - data analysis from the MAVIS trial.

BACKGROUND: Older people are less likely to be included in clinical trials. Little is known about factors influencing older people's decisions about participating in clinical trials. OBJECTIVES: To examine the views of older people about participating in clinical trials. METHODS: Postal questionnaire to 801 participants who had completed the MAVIS nutrition trial, aged 65 yrs and older. Closed and open questions sought participants' views about factors important to them when deciding to take part in a trial, features of the MAVIS trial they liked and disliked and changes they would suggest. RESULTS: 540 (59% of MAVIS trial participants) returned the questionnaire. The most important reasons reported for taking part in the trial were helping the research team and medical knowledge, and helping other older people. Participants valued good communication with the trial staff and good organisation. Participants reported concerns about swallowing pills and taking a placebo. Participants reported that future participation in trials could be influenced by poor health status. LIMITATIONS: This questionnaire surveyed older participants who had taken part in a randomised controlled trial. It did not elicit the views of people who had withdrawn or never decided to take part in the trial. CONCLUSIONS: Older people report altruistic reasons for taking part in trials. Simple trial designs, which minimise demands on participants and maintain good communications should be preferred. Explaining the need for older people, despite poor health, to participate in trials may help the generalisability of clinical trials.

Systematic review of long-term lifestyle interventions to prevent weight gain and morbidity in adults.

The aim of this article is to determine the effectiveness of long-term lifestyle interventions for the prevention of weight gain and morbidity in adults. Prevention of weight gain is important in adults who are of normal weight, overweight and obese. A systematic review of controlled trials of lifestyle interventions in adults with a body mass index of less than 35 kg m(-2) with at least 2 years of follow-up was carried out. Eleven of 39 comparisons produced significant improvement in weight between groups at 2 years or longer with mean difference weight change ranging from -0.5 to -11.5 kg. Effective interventions included a 600 kcal/day deficit diet deficit/low-fat diet (with and without meal replacements), low-calorie diet, Weight Watchers diet, low-fat non-reducing diet, diet with behaviour therapy, diet with exercise, diet with exercise and behaviour therapy. Adding meal replacements to a low-fat diet (with and without exercise and behaviour therapy) produced significant improvement in weight. Head-to-head interventions failed to show significant effect on weight with the exception of a Mediterranean diet with behaviour therapy compared with low-fat diet. Diet with exercise and/or behaviour therapy demonstrated significant reduction in hypertension and improvement in risk of metabolic syndrome and diabetes compared with no treatment control. Lifestyle interventions demonstrated significant improvement in weight, reduction in hypertension and reduction in risk of type 2 diabetes and the metabolic syndrome.

Systematic review and meta-analyses of studies of glutamine supplementation in haematopoietic stem cell transplantation.

It is unclear whether supplemental glutamine is of benefit in haematopoietic stem cell transplantation (HSCT). We performed a systematic review and meta-analyses using Cochrane methodology. Seventeen randomized controlled trials (RCTs) were found. There was considerable heterogeneity between studies in terms of patient demographics and glutamine administration schedule. Many of the studies were small and scored poorly on methodological quality. Oral glutamine may reduce mucositis (average mucositis score: standard mean difference -0.38, 95% confidence interval (CI) -0.59 to -0.16) and days of opioids (mean difference -1.95 days, 95% CI -3.66 to -0.25) and GVHD (relative risk 0.42, 95% CI 0.21-0.85). Glutamine (i.v.) may reduce clinical infections (relative risk 0.75, 95% CI 0.58 to 0.97) and positive cultures (relative risk 0.72, 95% CI 0.57-0.91) but may also increase the risk of relapse (relative risk 2.91, 95% CI 1.34-6.29) but this is based on only two small studies. There was no effect of oral or i.v. glutamine on overall transplant-related mortality at day +100. In conclusion, there may be beneficial effects of glutamine in HSCT but larger, well-designed studies are required to confirm the beneficial effects and investigate possible adverse effects.

Does taking vitamin, mineral and fatty acid supplements prevent cognitive decline? A systematic review of randomized controlled trials.

BACKGROUND: Observational studies have shown associations between nutritional status and cognition in later life but evidence from intervention studies is unclear. The present study systematically reviewed the evidence on the effect of nutrient supplementation on cognitive function in people aged >or=65 years. METHODS: Databases including MEDLINE and EMBASE were searched up to 1 September 2006. Randomized controlled trials using at least one kind of vitamin, mineral or omega-3 fatty acid, evaluating standardized neuropsychological test(s), were included. There were no restrictions on participants' baseline nutritional status or cognitive function. Quality assessment and data abstraction were conducted by one author and checked by another. RESULTS: Of 4229 articles retrieved, 22 trials (3442 participants) were identified. Many were small, short duration and of poor methodology. Only 16 out of 122 cognitive tests were significantly different between groups. A meta-analysis showed no significant effect of taking B vitamins or antioxidant vitamins on global cognitive function. There was insufficient evidence to evaluate the effect of omega-3 fatty acids on any cognitive domains. CONCLUSION: There was little evidence of a beneficial effect from taking B vitamins or antioxidant supplements on global cognitive function in later life. Larger-scale randomized controlled trials of longer duration in selected age groups are needed.

Systematic review of the use of financial incentives in treatments for obesity and overweight.

Nine studies met the criteria for inclusion in this systematic review of randomized controlled trials of treatments for obesity and overweight involving the use of financial incentives, with reported follow-up of at least 1 year. All included trials were of behavioural obesity treatments. Justification of sample size and blinding procedure were not mentioned in any study. Attrition was well described in three studies and no study was analysed on an intention to treat basis. Participants were mostly women recruited through media advertisements. Mean age ranged from 35.7 to 52.8 years, and mean body mass index from 29.3 to 31.8 kg m(-2). Results from meta-analysis showed no significant effect of use of financial incentives on weight loss or maintenance at 12 months and 18 months. Further sub-analysis by mode of delivery and amount of incentives although also non-statistically significant were suggestive of very weak trends in favour of use of amounts greater than 1.2% personal disposable income, rewards for behaviour change rather than for weight, rewards based on group performance rather than for individual performance and rewards delivered by non-psychologists rather than delivered by psychologists.

Long-term weight loss effects on all cause mortality in overweight/obese populations.

This systematic review assesses the long-term effectiveness of weight loss on all cause mortality in overweight/obese people. Medline, Embase and Cinahl were searched (1966-2005). Cohort studies and trials on participants with body mass index > or =25 kg m(-2), with weight change and mortality with > or =2-year follow-up, were included finally identifying 11 papers based on eight studies. There may be gender differences in the benefits for all cause mortality. The impact of weight loss in men on mortality was not clear with some studies indicating weight loss to be detrimental, while a recent cohort study showed benefits, if it were a personal decision. Other studies with no gender separation had similarly mixed results. However, one study indicated that overweight/obese women with obesity-related illness, who lost weight intentionally within 1 year, had significantly reduced mortality rates of 19-25%. In contrast, studies of overweight/obese diabetics irrespective of gender showed significant benefit of intentional weight loss on mortality in a meta-analysis, hazard ratios = 0.75 (0.67-0.83). There is some evidence that intentional weight loss has long-term benefits on all cause mortality for women and more so for diabetics. Long-term effects especially for men are not clear and need further investigation.

Nutritional supplementation for hip fracture aftercare in older people.

BACKGROUND: Older people with hip fractures are often malnourished at the time of fracture, and have poor food intake subsequently. OBJECTIVES: To review the effects of nutritional interventions in older people recovering from hip fracture. SEARCH STRATEGY: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (December 2005), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2006, Issue 1), MEDLINE, six other databases and reference lists. We contacted investigators and handsearched journals. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials of nutritional interventions for people aged over 65 years with hip fracture. DATA COLLECTION AND ANALYSIS: Both authors independently selected trials, extracted data and assessed trial quality. We sought additional information from trialists, and pooled data for primary outcomes. MAIN RESULTS: Twenty-one randomised trials involving 1727 participants were included. Overall trial quality was poor, specifically regarding allocation concealment, assessor blinding and intention-to-treat analysis, and limited availability of outcome data. Eight trials evaluated oral multinutrient feeds: providing non-protein energy, protein, some vitamins and minerals. Oral feeds had no statistically significant effect on mortality (15/161 versus 17/176; relative risk (RR) 0.89, 95% confidence interval (CI) 0.47 to 1.68) but may reduce 'unfavourable outcome' (combined outcome of mortality and survivors with medical complications) (14/66 versus 26/73; RR 0.52, 95% CI 0.32 to 0.84). Four trials examining nasogastric multinutrient feeding showed no evidence of an effect on mortality (RR 0.99, 95% CI 0.50 to 1.97) but the studies were heterogeneous regarding case mix. Nasogastric feeding was poorly tolerated. There was insufficient information for other outcomes. Increasing protein intake in an oral feed was tested in four trials. There was no evidence for an effect on mortality (RR 1.42, 95% CI 0.85 to 2.37). Protein supplementation may have reduced the number of long term medical complications. Two trials, testing intravenous vitamin B1 and other water soluble vitamins, or 1-alpha-hydroxycholecalciferol (an active form of vitamin D) respectively, produced no evidence of effect for either supplement. One trial, evaluating dietetic assistants to help with feeding, showed a trend for a reduction in mortality (RR 0.57, 99% CI 0.29 to 1.11). AUTHORS' CONCLUSIONS: Some evidence exists for the effectiveness of oral protein and energy feeds, but overall the evidence for the effectiveness of nutritional supplementation remains weak. Adequately sized trials are required which overcome the methodological defects of the reviewed studies. In particular, the role of dietetic assistants requires further evaluation.