Study protocol for BeWEL: the impact of a BodyWEight and physicaL activity intervention on adults at risk of developing colorectal adenomas

Development and validation of a lifestyle-based model for colorectal cancer risk prediction: the LiFeCRC score

BACKGROUND

Nutrition and lifestyle have been long established as risk factors for colorectal cancer (CRC). Modifiable lifestyle behaviours bear potential to minimize long-term CRC risk; however, translation of lifestyle information into individualized CRC risk assessment has not been implemented. Lifestyle-based risk models may aid the identification of high-risk individuals, guide referral to screening and motivate behaviour change. We therefore developed and validated a lifestyle-based CRC risk prediction algorithm in an asymptomatic European population.

METHODS

The model was based on data from 255,482 participants in the European Prospective Investigation into Cancer and Nutrition (EPIC) study aged 19 to 70 years who were free of cancer at study baseline (1992-2000) and were followed up to 31 September 2010. The model was validated in a sample comprising 74,403 participants selected among five EPIC centres. Over a median follow-up time of 15 years, there were 3645 and 981 colorectal cancer cases in the derivation and validation samples, respectively. Variable selection algorithms in Cox proportional hazard regression and random survival forest (RSF) were used to identify the best predictors among plausible predictor variables. Measures of discrimination and calibration were calculated in derivation and validation samples. To facilitate model communication, a nomogram and a web-based application were developed.

RESULTS

The final selection model included age, waist circumference, height, smoking, alcohol consumption, physical activity, vegetables, dairy products, processed meat, and sugar and confectionary. The risk score demonstrated good discrimination overall and in sex-specific models. Harrell's C-index was 0.710 in the derivation cohort and 0.714 in the validation cohort. The model was well calibrated and showed strong agreement between predicted and observed risk. Random survival forest analysis suggested high model robustness. Beyond age, lifestyle data led to improved model performance overall (continuous net reclassification improvement = 0.307 (95% CI 0.264-0.352)), and especially for young individuals below 45 years (continuous net reclassification improvement = 0.364 (95% CI 0.084-0.575)).

CONCLUSIONS

LiFeCRC score based on age and lifestyle data accurately identifies individuals at risk for incident colorectal cancer in European populations and could contribute to improved prevention through motivating lifestyle change at an individual level.

Motivational interviewing in eHealth and telehealth interventions for weight loss: A systematic review

The alarming prevalence of adult obesity warrants consideration of treatments with broad reach; digital health interventions meet this need and have demonstrated efficacy for weight loss. One approach that can be delivered remotely is motivational interviewing - a counseling style that helps resolve ambivalence to change unhealthy behavior. This is the first review to systematically examine eHealth and telehealth interventions that incorporate motivational interviewing for weight loss. We searched four electronic databases (PubMed, Embase, PsycInfo, CINAHL) for publications from November 2009-May 2018. Included papers were weight loss RCTs conducted among adults with overweight or obesity that examined eHealth or telehealth interventions with motivational interviewing, compared to any type of treatment arm without it. Results were presented separately by comparison arm (control vs. active comparator). Sixteen papers (15 trials) were included. Twelve used telephone-based counseling to deliver motivational interviewing, two used email and phone, and one used online chats. When compared to a no-treatment control arm, the motivational interviewing arm was associated with greater weight loss on 6 of 11 occasions, but performed better than an active comparator on only 1 of 7 occasions. Retention and engagement were generally high, though few trials examined the relation with weight loss. No trial had high risk of bias, but five lacked power calculations and only two reported fidelity to motivational interviewing. Telephone-based interventions that incorporate motivational interviewing hold promise as effective obesity treatments. There is a dearth of evidence to support the use of motivational interviewing via eHealth, signaling a needed research area.

Healthy eating interventions in adults living with and beyond colorectal cancer: a systematic review

BACKGROUND

Rates of cancer survival are increasing, with more people living with and beyond cancer. Lifestyle recommendations for cancer survivors are based largely on extrapolation from cancer prevention recommendations. The present study aimed to systematically review the literature on randomised controlled trials (RCTs) focusing on healthy eating interventions in people with colorectal cancer (CRC).

METHODS

A structured search of electronic databases was conducted in March 2018 using medical subject headings (MeSH) and text words related to CRC and diet. The results of the literature searches were uploaded to online software for data management. Titles and abstracts were screened based on the inclusion and exclusion criteria and data were extracted. Quality of data was assessed using the Cochrane Handbook.

RESULTS

Seven studies were identified, including six RCTs and one RCT protocol, with a total of 2233 participants from six studies, of whom 1010 (45%) had CRC. Three studies assessed anthropometrics demonstrating participants who received dietary intervention had a greater reduction in measurements. Six studies assessed changes in dietary components; however, only one demonstrated an increase in dietary fibre. Two studies reported improvements in quality of life favouring dietary intervention groups.

CONCLUSIONS

The quality of identified studies was variable, with limited evidence to support dietary intervention improving dietary intake in people living with or after CRC. Studies to date have not been based on robust study design that has combined all dietary interventions linked to CRC. As a result of the heterogeneity of the studies identified, it was difficult to draw strong conclusions.

Availability and feasibility of structured, routine collection of comorbidity data in a colorectal cancer multi-disciplinary team (MDT) setting

PURPOSE

Availability of comorbidity assessment at multi-disciplinary team (MDT) discussions is cornerstone in making the MDT process more robust and decisive in optimising treatment and improving quality of survivorship. Comorbidity assessments using tools, such as the ACE-27 questionnaire would aid in optimising the decision-making process at MDTs so that treatment decisions can be made without delay. This study determined the availability of comorbidity data in a CRC MDT and the feasibility of routine comorbidity data collection using the validated ACE-27 questionnaire. Secondary aims determined the optimal time and method of collecting comorbidity data.

METHODS

A retrospective mapping exercise (phase I; 6-months) examined the availability of comorbidity data within the MDT. Phase II prospectively collected comorbidity data using ACE-27 for a 3-month period following a short pilot.

RESULTS

In phase I, 73/135 (54%) patients had comorbidity data readily available informing the MDT discussion; 62 patients lacked this information. After a review of the patient records, it was clear that 41 of these 62 also had comorbidities and 21 out of the 135 had ≥ 2 major system disorders. Common referral sources to the MDT were surgical outpatient clinics (42%) and the endoscopy unit (13%). The average lead-time from referral to MDT discussion was 14 days. In phase II, an ACE-27 questionnaire was prospectively administered in 50 patients, mean age 54 years (range 20-84). Male: female ratio 26:24. Average time to administer ACE-27 was 4.8 min (range 1-15).

CONCLUSIONS

The phase I study confirmed the widely acknowledged view of poor comorbidity data availability within a CRC MDT. Phase II demonstrated the feasibility of routinely collecting comorbidity data using ACE-27.

The impact of social deprivation on the response to a randomised controlled trial of a weight management intervention (BeWEL) for people at increased risk of colorectal cancer

BACKGROUND

Although 45% of colorectal cancer (CRC) cases may be avoidable through appropriate lifestyle and weight management, health promotion interventions run the risk of widening health inequalities. The BeWEL randomised controlled trial assessed the impact of a diet and activity programme in overweight adults who were diagnosed with a colorectal adenoma, demonstrating a significantly greater weight loss at 12 months in intervention participants than in controls. The present study aimed to compare BeWEL intervention outcomes by participant deprivation status.

METHODS

The intervention group of the BeWEL trial (n = 163) was classified by the Scottish Index of Multiple Deprivation (SIMD) quintiles into 'more deprived' (SIMD 1-2, n = 58) and 'less deprived' (SIMD 3-5, n = 105). Socio-economic and lifestyle variables were compared at baseline to identify potential challenges to intervention adherence in the more deprived. Between group differences at 12 months in primary outcome (change in body weight) and secondary outcomes (cardiovascular risk factors, diet, physical activity, knowledge of CRC risk and psychosocial variables) were assessed by deprivation status.

RESULTS

At baseline, education (P = 0.001), income (P < 0.001), spending on physical activity (P = 0.003) and success at previous weight loss attempts (P = 0.007) were significantly lower in the most deprived. At 12 months, no between group differences by deprivation status were detected for changes in primary and main secondary outcomes.

CONCLUSIONS

Despite potential barriers faced by the more deprived participants, primary and most secondary outcomes were comparable between groups, indicating that this intervention is unlikely to worsen health inequalities and is equally effective across socio-economic groups.

Effect of lifestyle interventions on cardiovascular risk factors among adults without impaired glucose tolerance or diabetes: A systematic review and meta-analysis

Structured lifestyle interventions can reduce diabetes incidence and cardiovascular disease (CVD) risk among persons with impaired glucose tolerance (IGT), but it is unclear whether they should be implemented among persons without IGT. We conducted a systematic review and meta-analyses to assess the effectiveness of lifestyle interventions on CVD risk among adults without IGT or diabetes. We systematically searched MEDLINE, EMBASE, CINAHL, Web of Science, the Cochrane Library, and PsychInfo databases, from inception to May 4, 2016. We selected randomized controlled trials of lifestyle interventions, involving physical activity (PA), dietary (D), or combined strategies (PA+D) with follow-up duration ≥12 months. We excluded all studies that included individuals with IGT, confirmed by 2-hours oral glucose tolerance test (75g), but included all other studies recruiting populations with different glycemic levels. We stratified studies by baseline glycemic levels: (1) low-range group with mean fasting plasma glucose (FPG) <5.5mmol/L or glycated hemoglobin (A1C) <5.5%, and (2) high-range group with FPG ≥5.5mmol/L or A1C ≥5.5%, and synthesized data using random-effects models. Primary outcomes in this review included systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), and triglycerides (TG). Totally 79 studies met inclusion criteria. Compared to usual care (UC), lifestyle interventions achieved significant improvements in SBP (-2.16mmHg[95%CI, -2.93, -1.39]), DBP (-1.83mmHg[-2.34, -1.31]), TC (-0.10mmol/L[-0.15, -0.05]), LDL-C (-0.09mmol/L[-0.13, -0.04]), HDL-C (0.03mmol/L[0.01, 0.04]), and TG (-0.08mmol/L[-0.14, -0.03]). Similar effects were observed among both low-and high-range study groups except for TC and TG. Similar effects also appeared in SBP and DBP categories regardless of follow-up duration. PA+D interventions had larger improvement effects on CVD risk factors than PA alone interventions. In adults without IGT or diabetes, lifestyle interventions resulted in significant improvements in SBP, DBP, TC, LDL-C, HDL-C, and TG, and might further reduce CVD risk.

Metformin therapy and the risk of colorectal adenoma in patients with type 2 diabetes: A meta-analysis

BACKGROUND

Existing data evaluating the impact of metformin on the colorectal adenoma (CRA) risk in patients suffering from type 2 diabetes (T2D) are limited and controversial. We therefore summarized the studies currently available and assessed the relationship between metformin treatment and risk of CRA in T2D patients.

METHODS

We systematically searched databases for eligible studies that explored the impact of metformin treatment on the occurrence of CRA in T2D patients from inception to June 2016. The summary odds ratio (OR) estimates with their 95% confidence interval (CI) were derived using random-effect, generic inverse variance methods. Sensitivity analysis and subgroup analysis were performed.

RESULTS

Seven studies involving 7178 participants met the inclusion criteria. The pooling showed that metformin therapy has a 27% decrease in the CRA risk (OR, 0.73; 95% CI, 0.58 - 0.90). In subgroup analysis, we detected that metformin exhibits significant chemoprevention effects in Asia region (OR, 0.68; 95% CI, 0.48 - 0.96). Similar results were identified in both studies with adjusted ORs and high-quality studies (OR, 0.66; 95% CI, 0.50 - 0.86 and OR, 0.70; 95% CI, 0.58 - 0.84, respectively). Of note, an inverse relationship was noted that metformin therapy may result in a significant decrease in the advanced adenoma risk (OR, 0.52; 95% CI, 0.38 - 0.72). Low heterogeneity was observed, however, the results remained robust in multiple sensitivity analyses.

CONCLUSIONS

This meta-analysis indicates that metformin therapy is correlated with a significant decrease in the risk of CRA and advanced adenoma in T2D patients. Further confirmatory studies are warranted.

Effect of lifestyle interventions on glucose regulation among adults without impaired glucose tolerance or diabetes: A systematic review and meta-analysis

This study systematically assessed the effectiveness of lifestyle interventions on glycemic indicators among adults (⩾18years) without IGT or diabetes. Randomized controlled trials using physical activity (PA), diet (D), or their combined strategies (PA+D) with follow-up ⩾12months were systematically searched from multiple electronic-databases between inception and May 4, 2016. Outcome measures included fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), fasting insulin (FI), homeostasis model assessment-estimated insulin resistance (HOMA-IR), and bodyweight. Included studies were divided into low-range (FPG <5.5mmol/L or HbA1c <5.5%) and high-range (FPG ⩾5.5mmol/L or HbA1c ⩾5.5%) groups according to baseline glycemic levels. Seventy-nine studies met inclusion criteria. Random-effect models demonstrated that compared with usual care, lifestyle interventions achieved significant reductions in FPG (-0.14mmol/L [95%CI, -0.19, -0.10]), HbA1c (-0.06% [-0.09, -0.03]), FI (%change: -15.18% [-20.01, -10.35]), HOMA-IR (%change: -22.82% [-29.14, -16.51]), and bodyweight (%change: -3.99% [-4.69, -3.29]). The same effect sizes in FPG reduction (0.07) appeared among both low-range and high-range groups. Similar effects were observed among all groups regardless of lengths of follow-up. D and PA+D interventions had larger effects on glucose reduction than PA alone. Lifestyle interventions significantly improved FPG, HbA1c, FI, HOMA-IR, and bodyweight among adults without IGT or diabetes, and might reduce progression of hyperglycemia to type 2 diabetes mellitus.

Lifestyle change in the cancer setting using 'the teachable moment': protocol for a proof-of-concept pilot in a urology service

BACKGROUND

Previous research has shown diagnosis or screening for cancer may be a 'teachable moment' for prevention through lifestyle change. Previous trials have been successful but have been delivered via national programmes targeting patients being screened for colorectal cancer. This manuscript reports the protocol for a proof-of-concept study to assess the feasibility and acceptability of a lifestyle change service targeting men suspected or diagnosed with cancer of the prostate in a secondary care cancer service within the UK.

METHODS

Lifestyle change will be promoted through integration of a lifestyle change service in a urology department in one NHS Board. The service is delivered by a Health Psychologist and uses motivational interviewing and behavioural change techniques to motivate and support patients to consider and address topics such as increasing physical activity and a healthy diet, smoking cessation, alcohol reduction and weight loss. A service evaluation will assess feasibility and acceptability via a patient experience survey, a survey exploring staff knowledge, attitudes and practice, pre- and post-intervention lifestyle behaviour survey and an audit of routine patient database.

DISCUSSION

This pilot will assess the viability of using cancer testing and diagnosis as a teachable moment for lifestyle change in a unique population (i.e. men with suspected cancer of the prostate). If successful, this approach offers potential for preventative services to enhance routine and person-centred clinical cancer care provided within secondary care settings.

Can a lifestyle intervention be offered through NHS breast cancer screening? Challenges and opportunities identified in a qualitative study of women attending screening

Background

Around one third of breast cancers in post-menopausal women could be prevented by decreasing body fatness and alcohol intake and increasing physical activity. This study aimed to explore views and attitudes on lifestyle intervention approaches in order to inform the proposed content of a lifestyle intervention programme amongst women attending breast cancer screening.

Methods

Women attending breast cancer screening clinics in Dundee and Glasgow, were invited to participate in focus group discussions (FGD) by clinic staff. The groups were convened out with the clinic setting and moderated by an experienced researcher who attained brief details on socio-demographic background and audio-recorded the discussions. Data analysis was guided by the framework approach. The main topics of enquiry were: Understanding of risk of breast cancer and its prevention, views on engaging with a lifestyle intervention programme offered through breast cancer screening and programme design and content.

Results

Thirty one women attended 5 focus groups. Participant ages ranged from 51 to 78 years and 38 % lived in the two most deprived quintiles of residential areas. Women were generally positive about being offered a programme at breast cancer screening but sceptical about lifestyle associated risk, citing genetics, bad luck and knowing women with breast cancer who led healthy lifestyles as reasons to query the importance of lifestyle. Engagement via clinic staff and delivery of the programme by lifestyle coaches out with the screening setting was viewed favourably. The importance of body weight, physical activity and alcohol consumption with disease was widely known although most were surprised at the association with breast cancer. They were particularly surprised about the role of alcohol and resistant to thinking about themselves having a problem. They expressed frustration that lifestyle guidance was often conflicting and divergent over time. The concept of focussing on small lifestyle changes, which were personalised, supported socially and appropriate to age and ability were welcomed.

Conclusions

Offering access to a lifestyle programme through breast screening appears acceptable. Explaining the relevance of the target behaviours for breast cancer health, endorsing and utilising consistent messages and identifying personalised, mutually agreed, behaviour change goals provides a framework for programme development.

Awareness of Lifestyle and Colorectal Cancer Risk: Findings from the BeWEL Study

It is estimated that 47% of colorectal cancers (CRC) could be prevented by appropriate lifestyles. This study aimed to identify awareness of the causes of CRC in patients who had been diagnosed with a colorectal adenoma through the Scottish Bowel Screening Programme and subsequently enrolled in an intervention trial (using diet and physical activity education and behavioural change techniques) (BeWEL). At baseline and 12-month follow-up, participants answered an open-ended question on factors influencing CRC development. Of the 329 participants at baseline, 40 (12%) reported that they did not know any risk factors and 36 (11%) failed to identify specific factors related to diet and activity. From a potential knowledge score of 1 to 6, the mean score was 1.5 (SD 1.1, range 0 to 5) with no difference between intervention and control groups. At follow-up, the intervention group had a significantly greater knowledge score and better weight loss, diet, and physical activity measures than the control group. Awareness of relevant lifestyle factors for CRC remains low in people at increased risk of the disease. Opportunities within routine NHS screening to aid the capability (including knowledge of risk factors) of individuals to make behavioural changes to reduce CRC risk deserve exploration.

Colorectal adenomas and diabetes: implications for disease prevention

AIM

This study assessed the baseline type II diabetes mellitus (T2DM) risk status among overweight patients with screen-detected colorectal adenomas and explored the implications of the findings for preventative practice.

METHOD

Participants aged between 50 and 74 years (73% of whom were men) were recruited from four Scottish health boards and assessed for diabetes risk. Participants were categorized as at 'high' diabetes risk if glycated haemoglobin (HbA1c) was between 6.0 and 6.4% or fasting plasma glucose (FPG) was between 5.5 and 6.9 mmol/l and as potentially undiagnosed T2DM when HbA1c ≥ 6.5% or FPG ≥ 7 mmol/l. Secondary outcome measures included anthropometric measurements, blood pressure and the plasma lipid profile. The tests were repeated at 12 months and diabetes risk categories were reassessed following intervention procedures.

RESULTS

Forty-seven (14.3%) of the 329 participants had a preexisting diagnosis of T2DM. Of the remainder with complete biochemistry results (n = 250), 19 (7.6%) were classified as having potentially undiagnosed T2DM and 125 (50.0%) as being at high risk of developing diabetes. More than a quarter of participants in all categories had raised waist circumference, hypertension and plasma lipids, indicative of raised cardiovascular risk. At 12 months' follow-up, the diabetes risk category diminished in 20% of the intervention group vs 11% in the controls [OR 2.26 (95% CI 1.03-4.96)].

CONCLUSION

Our results suggest that a diagnosis of adenoma in overweight patients provides a health service opportunity for diabetes assessment, prevention and management in a high-risk population at a potentially teachable moment.

Why are some people more successful at lifestyle change than others? Factors associated with successful weight loss in the BeWEL randomised controlled trial of adults at risk of colorectal cancer

BACKGROUND

The BeWEL (BodyWEight and physicaL activity) randomised controlled trial demonstrated that a weight management programme offered in the colorectal cancer screening setting was effective. However, the differential responses of participants to the programme were notable. This study aimed to explore the factors associated with success and to identify implications for future programme design.

METHODS

Analyses were conducted of quantitative data (n = 148) from the BeWEL intervention group to compare demographic and psychosocial characteristics and lifestyle changes in those who met and exceeded the target 7% weight loss ('super-achievers') with those who achieved only 'moderate' or 'low' amounts of weight loss (2-7% loss, or <2% loss, respectively). In-depth qualitative interviews (n = 24) explored in detail the motivations, actions, pathways to weight loss and circumstances of study participants.

RESULTS

Over the 12 month intervention period, mean percentage weight loss of super-achievers (n = 33) was 11.5%, compared with moderate-achievers (n = 58) who lost 4.2%, and low-achievers (n = 57) who gained 0.8%. Compared to other groups, super- achievers increased their fruit and vegetable intake (p < 0.01) and physical activity (step count, p < 0.01). 'Super-achievers' did not differ in baseline demographic characteristics from other participants. However, significantly fewer reported that their activities were limited by physical and emotional health and they were more likely to perceive their current diet as harmful. Qualitative analyses found no consistent patterns among super-achievers in relation to some factors identified as important in previous studies, such as social support. However, super-achievers shared several characteristics such as determination and consistency in their engagement with the intervention, receptivity to new information and prompts, previous positive experience of changing health behaviours, being motivated by early success, making changes routine, and an ability to devise and apply strategies for dealing with setback and 'relapse' triggers.

CONCLUSIONS

Successful lifestyle change depends on active engagement as well as effective intervention ingredients. Weight loss interventions are likely to be more effective where they can adapt to participants' differing characteristics and needs, while also providing core elements likely to build success.

The impact of a bodyweight and physical activity intervention (BeWEL) initiated through a national colorectal cancer screening programme: randomised controlled trial

OBJECTIVE

To evaluate the impact of a diet and physical activity intervention (BeWEL) on weight change in people with a body mass index >25 weight (kg)/height (m)(2) at increased risk of colorectal cancer and other obesity related comorbidities.

DESIGN

Multicentre, parallel group, randomised controlled trial.

SETTING

Four Scottish National Health Service health boards.

PARTICIPANTS

329 overweight or obese adults (aged 50 to 74 years) who had undergone colonoscopy after a positive faecal occult blood test result, as part of the national bowel screening programme, and had a diagnosis of adenoma confirmed by histopathology. 163 were randomised to intervention and 166 to control.

INTERVENTION

Participants were randomised to a control group (weight loss booklet only) or 12 month intervention group (three face to face visits with a lifestyle counsellor plus monthly 15 minute telephone calls). A goal of 7% reduction in body weight was set and participants received a personalised energy prescription (2508 kJ (600 kcal) below that required for weight maintenance) and bodyweight scales. Motivational interviewing techniques explored self assessed confidence, ambivalence, and personal values concerning weight. Behavioural strategies included goal setting, identifying intentions of implementation, self monitoring of body weight, and counsellor feedback about reported diet, physical activity, and weight change.

MAIN OUTCOME MEASURES

The primary outcome was weight change over 12 months. Secondary outcomes included changes in waist circumference, blood pressure, fasting cardiovascular biomarkers, and glucose metabolism variables, physical activity, diet, and alcohol consumption.

RESULTS

At 12 months, data on the primary outcome were available for 148 (91%) participants in the intervention group and 157 (95%) in the control group. Mean weight loss was 3.50 kg (SD 4.91) (95% confidence interval 2.70 to 4.30) in the intervention group compared with 0.78 kg (SD 3.77) (0.19 to 1.38) in the control group. The group difference was 2.69 kg (95% confidence interval 1.70 to 3.67). Differences between groups were significant for waist circumference, body mass index, blood pressure, blood glucose level, diet, and physical activity. No reported adverse events were considered to be related to trial participation.

CONCLUSIONS

Significant weight loss can be achieved by a diet and physical activity intervention initiated within a national colorectal cancer screening programme, offering considerable potential for risk reduction of disease in older adults.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN53033856.

Transtheoretical model stages of change for dietary and physical exercise modification in weight loss management for overweight and obese adults

BACKGROUND

Obesity is a global public health threat. The transtheoretical stages of change (TTM SOC) model has long been considered a useful interventional approach in lifestyle modification programmes, but its effectiveness in producing sustainable weight loss in overweight and obese individuals has been found to vary considerably. 

OBJECTIVES

To assess the effectiveness of dietary intervention or physical activity interventions, or both, and other interventions based on the transtheoretical model (TTM) stages of change (SOC) to produce sustainable (one year and longer) weight loss in overweight and obese adults.

SEARCH METHODS

Studies were obtained from searches of multiple electronic bibliographic databases. We searched The Cochrane Library, MEDLINE, EMBASE and PsycINFO. The date of the last search, for all databases, was 17 December 2013.

SELECTION CRITERIA

Trials were included if they fulfilled the criteria of randomised controlled clinical trials (RCTs) using the TTM SOC as a model, that is a theoretical framework or guideline in designing lifestyle modification strategies, mainly dietary and physical activity interventions, versus a comparison intervention of usual care; one of the outcome measures of the study was weight loss, measured as change in weight or body mass index (BMI); participants were overweight or obese adults only; and the intervention was delivered by healthcare professionals or trained lay people at the hospital and community level, including at home.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data, assessed studies for risk of bias and evaluated overall study quality according to GRADE (Grading of Recommendations Assessment, Development and Evaluation). We resolved disagreements by discussion or consultation with a third party. A narrative, descriptive analysis was conducted for the systematic review.

MAIN RESULTS

A total of three studies met the inclusion criteria, allocating 2971 participants to the intervention and control groups. The total number of participants randomised to the intervention groups was 1467, whilst 1504 were randomised to the control groups. The length of intervention was 9, 12 and 24 months in the different trials. The use of TTM SOC in combination with diet or physical activity, or both, and other interventions in the included studies produced inconclusive evidence that TTM SOC interventions led to sustained weight loss (the mean difference between intervention and control groups varied from 2.1 kg to 0.2 kg at 24 months; 2971 participants; 3 trials; low quality evidence). Following application of TTM SOC there were improvements in physical activity and dietary habits, such as increased exercise duration and frequency, reduced dietary fat intake and increased fruit and vegetable consumption (very low quality evidence). Weight gain was reported as an adverse event in one of the included trials. None of the trials reported health-related quality of life, morbidity, or economic costs as outcomes. The small number of studies and their variable methodological quality limit the applicability of the findings to clinical practice. The main limitations include inadequate reporting of outcomes and the methods for allocation, randomisation and blinding; extensive use of self-reported measures to estimate the effects of interventions on a number of outcomes, including weight loss, dietary consumption and physical activity levels; and insufficient assessment of sustainability due to lack of post-intervention assessments.

AUTHORS' CONCLUSIONS

The evidence to support the use of TTM SOC in weight loss interventions is limited by risk of bias and imprecision, not allowing firm conclusions to be drawn. When combined with diet or physical activity, or both, and other interventions we found very low quality evidence that it might lead to better dietary and physical activity habits. This systematic review highlights the need for well-designed RCTs that apply the principles of the TTM SOC appropriately to produce conclusive evidence about the effect of TTM SOC lifestyle interventions on weight loss and other health outcomes.

Meeting the challenges of recruitment to multicentre, community-based, lifestyle-change trials: a case study of the BeWEL trial

Background

Recruiting participants to multicentre, community-based trials is a challenge. This case study describes how this challenge was met for the BeWEL trial, which evaluated the impact of a diet and physical activity intervention on body weight in people who had had pre-cancerous bowel polyps.

Methods

The BeWEL trial was a community-based trial, involving centres linked to the Scottish National Health Service (NHS) colorectal cancer screening programme. BeWEL had a recruitment target of 316 and its primary recruitment route was the colonoscopy clinics of the Scottish Bowel Screening Programme.

Results

BeWEL exceeded its recruitment target but needed a 6-month no-cost extension from the funder to achieve this. The major causes of delay were lower consent rates (49% as opposed to 70% estimated from earlier work), the time taken for NHS research and development department approvals and the inclusion of two additional sites to increase recruitment, for which there were substantial bureaucratic delays. A range of specific interventions to increase recruitment, for example, telephone reminders and a shorter participant information leaflet, helped to increase the proportion of eligible individuals consenting and being randomized.

Conclusions

Recruitment to multicentre trials is a challenge but can be successfully achieved with a committed team. In a UK context, NHS research and development approval can be a substantial source of delay. Investigators should be cautious when estimating consent rates. If consent rates are less than expected, qualitative analysis might be beneficial, to try and identify the reason. Finally, investigators should select trial sites on the basis of a formal assessment of a site’s past performance and the likelihood of success in the trial being planned.

Trial registration

Current Controlled Trials ISRCTN53033856

Process evaluations for cluster-randomised trials of complex interventions: a proposed framework for design and reporting

BACKGROUND

Process evaluations are recommended to open the 'black box' of complex interventions evaluated in trials, but there is limited guidance to help researchers design process evaluations. Much current literature on process evaluations of complex interventions focuses on qualitative methods, with less attention paid to quantitative methods. This discrepancy led us to develop our own framework for designing process evaluations of cluster-randomised controlled trials.

METHODS

We reviewed recent theoretical and methodological literature and selected published process evaluations; these publications identified a need for structure to help design process evaluations. We drew upon this literature to develop a framework through iterative exchanges, and tested this against published evaluations.

RESULTS

The developed framework presents a range of candidate approaches to understanding trial delivery, intervention implementation and the responses of targeted participants. We believe this framework will be useful to others designing process evaluations of complex intervention trials. We also propose key information that process evaluations could report to facilitate their identification and enhance their usefulness.

CONCLUSION

There is no single best way to design and carry out a process evaluation. Researchers will be faced with choices about what questions to focus on and which methods to use. The most appropriate design depends on the purpose of the process evaluation; the framework aims to help researchers make explicit their choices of research questions and methods.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01425502.

Designing an intervention to help people with colorectal adenomas reduce their intake of red and processed meat and increase their levels of physical activity: a qualitative study

Background

Most cases of colorectal cancer (CRC) arise from adenomatous polyps and malignant potential is greatest in high risk adenomas. There is convincing observational evidence that red and processed meat increase the risk of CRC and that higher levels of physical activity reduce the risk. However, no definitive randomised trial has demonstrated the benefit of behaviour change on reducing polyp recurrence and no consistent advice is currently offered to minimise patient risk. This qualitative study aimed to assess patients’ preferences for dietary and physical activity interventions and ensure their appropriate and acceptable delivery to inform a feasibility trial.

Methods

Patients aged 60–74 included in the National Health Service Bowel Cancer Screening Programme (NHSBCSP) were selected from a patient tracking database. After a positive faecal occult blood test (FOBt), all had been diagnosed with an intermediate or high risk adenoma (I/HRA) at colonoscopy between April 2008 and April 2010. Interested patients and their partners were invited to attend a focus group or interview in July 2010. A topic guide, informed by the objectives of the study, was used. A thematic analysis was conducted in which transcripts were examined to ensure that all occurrences of each theme had been accounted for and compared.

Results

Two main themes emerged from the focus groups: a) experiences of having polyps and b) changing behaviour. Participants had not associated polyp removal with colorectal cancer and most did not remember being given any information or advice relating to this at the time. Heterogeneity of existing diet and physical activity levels was noted. There was a lack of readiness to change behaviour in many people in the target population.

Conclusions

This study has confirmed and amplified recently published factors involved in developing interventions to change dietary and physical activity behaviour in this population. The need to tailor the intervention to individuals, the lack of knowledge about the aetiology of colon cancer and the lack of motivation to change behaviour are critical factors.

Trial registration

Current Controlled Trials ISRCTN03320951

Population based cancer screening programmes as a teachable moment for primary prevention interventions. A review of the literature

Background and aim: Unhealthy diet, physical inactivity, and smoking are key risk factors for the major non-communicable diseases such as cancer, cardiovascular diseases, and diabetes. The screening procedure may represent an ideal setting for promoting healthy lifestyles as it represents a time when subjects are probably more inclined to consider a relationship between their own habits and their effects on health. The aim of this study is to review available evidence concerning interventions combining screening and primary prevention interventions, aimed at promoting the adoption of healthy lifestyles. Methods: We searched the MEDLINE and Cochrane library electronic databases for intervention studies of primary prevention interventions implemented in the context of established screening programmes, or of pilot screening projects, where the study design included a comparison group. Results: Comprehensive interventions are acceptable for asymptomatic subjects targeted for cancer screening, can result in improvements and may be cost–effective. A positive impact of these interventions in favoring the adoption of cancer protective dietary behaviors was observed in all studies. Conflicting results were instead reported with respect to physical activity, while no impact could be observed for interventions aimed to favor smoking cessation. Conclusions: The retrieved studies suggest that the screening setting may offer valuable opportunities to provide credible, potentially persuasive life style advice, reaching a wide audience. A multiple risk factor approach may maximize the benefit of behavioral change, as the same health related habits are associated not only with cancers targeted by screening interventions, but also with other cancers, coronary artery disease, and other chronic conditions, while unhealthy behaviors may be mutually reinforcing. In order to cover a maximum number of possibilities, health education programmes should include multiple strategies, integrating and combining models of individual, social, and environmental change.

Monosodium glutamate-induced diabetic mice are susceptible to azoxymethane-induced colon tumorigenesis

Obese people and diabetic patients are known to be high risk of colorectal cancer (CRC), suggesting need of a new preclinical animal model, by which to extensively study the diverse mechanisms, therapy and prevention. The present study aimed to determine whether experimental obese and diabetic mice produced by monosodium glutamate (MSG) treatment are susceptible to azoxymethane (AOM)-induced colon tumorigenesis using early biomarkers, aberrant crypts foci (ACF) and β-catenin-accumulated crypts (BCACs), of colorectal carcinogenesis. Male Crj:CD-1 (ICR) newborns were daily given four subcutaneous injections of MSG (2 mg/g body wt) to induce diabetes and obesity. They were then given four intraperitoneal injections of AOM (15 mg/kg body wt) or saline (0.1 ml saline/10 g body wt). Ten weeks after the last injection of AOM, the MSG-AOM mice had a significant increase in the multiplicity of BCAC (13.83 ± 7.44, P < 0.002), but not ACF (78.00 ± 11.20), when compare to the Saline-AOM mice (5.45 ± 1.86 of BCAC and 69.27 ± 8.06 of ACF). Serum biochemical profile of the MSG-treated mice with or without AOM showed hyperinsulinemia, hypercholesteremia and hyperglycemia. The mRNA expression of insulin-like growth factor-1 receptor (IGF-1R, P<0.01) was increased in the MSG-AOM mice, when compared with the mice given AOM alone. IGF-1R was immunohistochemically expressed in the BCAC, but not ACF, in the AOM-treated mice. Our findings suggest that the MSG mice are highly susceptible to AOM-induced colorectal carcinogenesis, suggesting potential utility of our MSG-AOM mice for further investigation of the possible underlying events that affect the positive association between obese/diabetes and CRC.

Detailed protocol for the lifestyle intervention in the BeWEL randomised controlled trial of weight loss in adults who have had a colorectal adenoma

INTRODUCTION

The BeWEL study is aimed at assessing the impact of a personalised lifestyle programme on body weight in people at risk of developing colorectal adenomas. The study is a two-arm multicentre randomised controlled trial comparing the BeWEL lifestyle programme against usual care. Over 12 months, 316 people who have had a colorectal adenoma removed through the national screening programme will be randomised to provide 80% power to detect a weight loss (primary outcome) of 7% over 12 months.

METHODS

The 12-month intervention will be delivered by lifestyle counsellors via three face-to-face visits followed by nine monthly telephone support calls. Consultant endorsement for the study will be stressed. An individualised caloric prescription based on estimates for weight maintenance -600 kcal will be calculated. Motivational interviewing techniques will be used to identify personal motivations for weight change and ways to improve perceived self-efficacy. The programme will utilise personalised diet and physical activity data from baseline measures to set behavioural goals. A range of behavioural strategies will be employed to support lifestyle change including goal setting, identifying specific implementation intentions, self-monitoring and feedback. Emphasis will be placed on self-monitoring body weight, and weighing scales will be provided. Programme acceptability will be explored postintervention with indepth interviews. Compliance and impact will be assessed by baseline and follow-up measures of diet by self-report, activity by accelerometry and anthropometry.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Tayside Committee on Medical Research Ethics. Dissemination of results will focus on publications in peer-reviewed journals, presentations at national/international cancer meetings and NHS groups. In addition, the work will be communicated to the public through forums such at The Scottish Cancer Prevention Network (http://www.cancerpreventionscotland.co.uk/). The trial is registered with Current Controlled Trials (International Standard Randomised Controlled Trials No: ISRCTN53033856).

Understanding the potential and challenges of adenoma treatment as a prevention opportunity: insights from the BeWEL formative study

OBJECTIVES

To explore prevention opportunities presented by colorectal adenoma diagnosis and inform engagement strategies for the BeWEL study (body weight and physical activity lifestyle intervention for colorectal cancer screening participants who have undergone adenoma removal).

METHODS

Qualitative study comprising 4 purposively sampled focus groups conducted in urban and rural areas in Tayside, Scotland, with different deprivation levels. Participants were men and women (n=17) aged 50-74 with BMI>25 kg/m(2) with removal of adenoma detected by colorectal cancer screening.

RESULTS

Adenoma diagnosis presents both opportunities and challenges for prevention. Some patients perceived adenoma as minor and not sufficiently motivating to act as a 'teachable moment'. Patients had low awareness of the relationship between adenoma and lifestyle factors, and received little information on prevention during screening and treatment. Consequently they interpreted post-treatment 'all clear' messages as validation of existing lifestyles, and did not see the relevance of prevention advice. Receptiveness increased when the association between lifestyle, adenoma recurrence and other illness was explained.

CONCLUSION

The study illustrates the value of exploratory research into patient understanding to improve communications and health services. Without unduly worrying patients, professionals should explain how to reduce risk of adenoma, cancer and other diseases, particularly through diet, physical activity and weight reduction.