Goal achievement and adaptive goal adjustment in a behavioral intervention for participants with prediabetes.

Participants with prediabetes were supported to achieve and maintain weight loss with a stage-based behavior change group program named PREview behavior Modification Intervention Toolbox (PREMIT). The tendency to engage in a process of goal adjustment was examined in relation to PREMIT attendance. Analyses were based on 1857 participants who had achieved ⩾8percent weight loss. Tendency to engage in a process of goal adjustment appeared not to be influenced by PREMIT attendance. Instead, results suggested that when unsure about reaching an intervention goal, participants were more likely to engage in a process of goal adjustment, possibly lessening distress due to potentially unachievable goals, either weight loss or maintenance.

Sociocognitive factors associated with lifestyle intervention attrition after successful weight loss among participants with prediabetes-The PREVIEW study.

INTRODUCTION: Major risk factors for type 2 diabetes are lifestyle choices such as lack of physical activity (PA) and poor diet. Many individuals either do not take part or struggle to complete interventions supporting lifestyle changes. Demographic and theory-based sociocognitive factors associated with PREVIEW intervention attrition after successful weight loss were examined. METHODS: Participants (1,856) who started the weight maintenance phase after completion of low-energy diet were retrospectively divided into three clusters depending on the point they left the trial. Discriminant analysis examined which demographic and theory-based sociocognitive variables were associated with cluster membership. RESULTS: Most of the participants were women and well-educated. Two discriminant functions were calculated (χ2 (24) = 247.0, p ≥ .05, d = 0.78). The demographic variables, such as age and ethnicity, and the social cognitive variable outcome expectancies on the other side were associated with cluster membership. Older age, Caucasian ethnicity, and fewer expected disadvantages of PA were associated with high success. DISCUSSION: The discriminant model gave insight into some factors associated with early attrition. For practitioners planning interventions it underlines the necessity to take extra attention to younger participants and to those being afraid that being physically active causes unpleasant ramifications.

PREVIEW study-influence of a behavior modification intervention (PREMIT) in over 2300 people with pre-diabetes: intention, self-efficacy and outcome expectancies during the early phase of a lifestyle intervention.

PURPOSE: Onset of type 2 diabetes (T2D) is often gradual and preceded by impaired glucose homeostasis. Lifestyle interventions including weight loss and physical activity may reduce the risk of developing T2D, but adherence to a lifestyle change is challenging. As part of an international T2D prevention trial (PREVIEW), a behavior change intervention supported participants in achieving a healthier diet and physically active lifestyle. Here, our aim was to explore the influence of this behavioral program (PREMIT) on social-cognitive variables during an 8-week weight loss phase. METHODS: PREVIEW consisted of an initial weight loss, Phase I, followed by a weight- maintenance, Phase II, for those achieving the 8-week weight loss target of ≥ 8% from initial bodyweight. Overweight and obese (BMI ≥25 kg/m2) individuals aged 25 to 70 years with confirmed pre-diabetes were enrolled. Uni- and multivariate statistical methods were deployed to explore differences in intentions, self-efficacy, and outcome expectancies between those who achieved the target weight loss ("achievers") and those who did not ("non-achievers"). RESULTS: At the beginning of Phase I, no significant differences in intentions, self-efficacy and outcome expectancies between "achievers" (1,857) and "non-achievers" (163) were found. "Non-achievers" tended to be younger, live with child/ren, and attended the PREMIT sessions less frequently. At the end of Phase I, "achievers" reported higher intentions (healthy eating χ2(1)=2.57; P <0.008, exercising χ2(1)=0.66; P <0.008), self-efficacy (F(2; 1970)=10.27, P <0.005), and were more positive about the expected outcomes (F(4; 1968)=11.22, P <0.005). CONCLUSION: Although statistically significant, effect sizes observed between the two groups were small. Behavior change, however, is multi-determined. Over a period of time, even small differences may make a cumulative effect. Being successful in behavior change requires that the "new" behavior is implemented time after time until it becomes a habit. Therefore, having even slightly higher self-efficacy, positive outcome expectancies and intentions may over time result in considerably improved chances to achieve long-term lifestyle changes.

Men and women respond differently to rapid weight loss: Metabolic outcomes of a multi-centre intervention study after a low-energy diet in 2500 overweight, individuals with pre-diabetes (PREVIEW).

AIMS: The PREVIEW lifestyle intervention study (ClinicalTrials.gov Identifier: NCT01777893) is, to date, the largest, multinational study concerning prevention of type-2 diabetes. We hypothesized that the initial, fixed low-energy diet (LED) would induce different metabolic outcomes in men vs women. MATERIALS AND METHODS: All participants followed a LED (3.4 MJ/810 kcal/daily) for 8 weeks (Cambridge Weight Plan). Participants were recruited from 8 sites in Europe, Australia and New Zealand. Those eligible for inclusion were overweight (BMI ≥ 25 kg/m2 ) individuals with pre-diabetes according to ADA-criteria. Outcomes of interest included changes in insulin resistance, fat mass (FM), fat-free mass (FFM) and metabolic syndrome Z-score. RESULTS: In total, 2224 individuals (1504 women, 720 men) attended the baseline visit and 2020 (90.8%) completed the follow-up visit. Following the LED, weight loss was 16% greater in men than in women (11.8% vs 10.3%, respectively) but improvements in insulin resistance were similar. HOMA-IR decreased by 1.50 ± 0.15 in men and by 1.35 ± 0.15 in women (ns). After adjusting for differences in weight loss, men had larger reductions in metabolic syndrome Z-score, C-peptide, FM and heart rate, while women had larger reductions in HDL cholesterol, FFM, hip circumference and pulse pressure. Following the LED, 35% of participants of both genders had reverted to normo-glycaemia. CONCLUSIONS: An 8-week LED induced different effects in women than in men. These findings are clinically important and suggest gender-specific changes after weight loss. It is important to investigate whether the greater decreases in FFM, hip circumference and HDL cholesterol in women after rapid weight loss compromise weight loss maintenance and future cardiovascular health.

Weight loss decreases self-reported appetite and alters food preferences in overweight and obese adults: Observational data from the DiOGenes study.

People with obesity often struggle to maintain their weight loss after a weight loss period. Furthermore, the effect of weight loss on appetite and food preferences remains unclear. Hence this study investigated the effect of weight loss on subjective appetite and food preferences in healthy, overweight and obese volunteers. A subgroup of adult participants (n = 123) from the Diet Obesity and Genes (DiOGenes) study (subgroup A) was recruited from across six European countries. Participants lost ≥8% of initial body weight during an 8-week low calorie diet (LCD). Subjective appetite and food preferences were measured before and after the LCD, in response to a standardized meal test, using visual analogue rating scales (VAS) and the Leeds Food Choice Questionnaire (FCQ). After the LCD, participants reported increased fullness (p < 0.05), decreased desire to eat (p < 0.05) and decreased prospective consumption (p < 0.05) after consuming the test meal. An interaction effect (visit x time) was found for hunger ratings (p < 0.05). Area under the curve (AUC) for hunger, desire to eat and prospective consumption was decreased by 18.1%, 20.2% and 21.1% respectively whereas AUC for fullness increased by 13.9%. Preference for low-energy products measured by the Food Preference Checklist (FPC) decreased by 1.9% before the test meal and by 13.5% after the test meal (p < 0.05). High-carbohydrate and high-fat preference decreased by 11.4% and 16.2% before the test meal and by 17.4% and 22.7% after the meal (p < 0.05). No other effects were observed. These results suggest that LCD induced weight loss decreases the appetite perceptions of overweight volunteers whilst decreasing their preference for high-fat-, high-carbohydrate-, and low-energy products.

Long-term weight-loss maintenance in obese patients with knee osteoarthritis: a randomized trial.

Background: A formula low-energy diet (LED) reduces weight effectively in obese patients with knee osteoarthritis, but the role of LED in long-term weight-loss maintenance is unclear.Objective: We aimed to determine the effect of intermittent LED compared with daily meal replacements on weight-loss maintenance and number of knee replacements over 3 y.Design: The design was a randomized trial with participants aged >50 y who had knee osteoarthritis and a body mass index [BMI (in kg/m2)] ≥30. Participants were recruited from the osteoarthritis outpatient clinic at Copenhagen University Hospital in Frederiksberg, Denmark; they had previously completed a 68-wk lifestyle intervention trial and achieved an average weight loss of 10.5 kg (10% of initial body weight). Participants were randomly assigned to either the intermittent treatment (IN) group with LED for 5 wk every 4 mo for 3 y or to daily meal replacements of 1-2 meals for 3 y [regular (RE) group]. Attention by dietitians and the amount of formula products were similar. Primary outcomes were changes in body weight and proportion of participants receiving knee replacements. Outcomes were analyzed on the intention-to-treat-population with the use of baseline-carried-forward imputation for missing data.Results: A total of 153 participants (means ± SDs: BMI: 33.3 ± 4.6; age: 63.8 ± 6.3 y; 83% women) were recruited between June and December 2009 and randomly assigned to the IN (n = 76) or RE (n = 77) group. A total of 53 and 56 participants, respectively, completed the trial. Weight increased by 0.68 and 1.75 kg in the IN and RE groups, respectively (mean difference: -1.06 kg; 95% CI: -2.75, 0.63 kg; P = 0.22). Alloplasty rates were low and did not differ (IN group: 8 of 76 participants; RE group: 12 of 77 participants; P = 0.35).Conclusions: After a mean 10% weight-loss and 1-y maintenance, additional use of daily meal replacements or intermittent LED resulted in weight-loss maintenance for 3 y. These results challenge the commonly held assumption that weight regain in the long term is inevitable. This trial was registered at clinicaltrials.gov as NCT00938808.

PREVIEW Behavior Modification Intervention Toolbox (PREMIT): A Study Protocol for a Psychological Element of a Multicenter Project.

BACKGROUND: Losing excess body weight and preventing weight regain by changing lifestyle is a challenging but promising task to prevent the incidence of type-2 diabetes. To be successful, it is necessary to use evidence-based and theory-driven interventions, which also contribute to the science of behavior modification by providing a deeper understanding of successful intervention components. OBJECTIVE: To develop a physical activity and dietary behavior modification intervention toolbox (PREMIT) that fulfills current requirements of being theory-driven and evidence-based, comprehensively described and feasible to evaluate. PREMIT is part of an intervention trial, which aims to prevent the onset of type-2 diabetes in pre-diabetics in eight clinical centers across the world by guiding them in changing their physical activity and dietary behavior through a group counseling approach. METHODS: The program development took five progressive steps, in line with the Public Health Action Cycle: (1) Summing-up the intervention goal(s), target group and the setting, (2) uncovering the generative psychological mechanisms, (3) identifying behavior change techniques and tools, (4) preparing for evaluation and (5) implementing the intervention and assuring quality. RESULTS: PREMIT is based on a trans-theoretical approach referring to valid behavior modification theories, models and approaches. A major "product" of PREMIT is a matrix, constructed for use by onsite-instructors. The matrix includes objectives, tasks and activities ordered by periods. PREMIT is constructed to help instructors guide participants' behavior change. To ensure high fidelity and adherence of program-implementation across the eight intervention centers standardized operational procedures were defined and "train-the-trainer" workshops were held. In summary PREMIT is a theory-driven, evidence-based program carefully developed to change physical activity and dietary behaviors in pre-diabetic people.

Atkins and other low-carbohydrate diets: hoax or an effective tool for weight loss?

CONTEXT: The Atkins diet books have sold more than 45 million copies over 40 years, and in the obesity epidemic this diet and accompanying Atkins food products are popular. The diet claims to be effective at producing weight loss despite ad-libitum consumption of fatty meat, butter, and other high-fat dairy products, restricting only the intake of carbohydrates to under 30 g a day. Low-carbohydrate diets have been regarded as fad diets, but recent research questions this view. STARTING POINT: A systematic review of low-carbohydrate diets found that the weight loss achieved is associated with the duration of the diet and restriction of energy intake, but not with restriction of carbohydrates. Two groups have reported longer-term randomised studies that compared instruction in the low-carbohydrate diet with a low-fat calorie-reduced diet in obese patients (N Engl J Med 2003; 348: 2082-90; Ann Intern Med 2004; 140: 778-85). Both trials showed better weight loss on the low-carbohydrate diet after 6 months, but no difference after 12 months. WHERE NEXT?: The apparent paradox that ad-libitum intake of high-fat foods produces weight loss might be due to severe restriction of carbohydrate depleting glycogen stores, leading to excretion of bound water, the ketogenic nature of the diet being appetite suppressing, the high protein-content being highly satiating and reducing spontaneous food intake, or limited food choices leading to decreased energy intake. Long-term studies are needed to measure changes in nutritional status and body composition during the low-carbohydrate diet, and to assess fasting and postprandial cardiovascular risk factors and adverse effects. Without that information, low-carbohydrate diets cannot be recommended.