Cognitive Training Therapy Improves the Effect of Hypocaloric Treatment on Subjects with Overweight/Obesity: A Randomised Clinical Trial

Dropout in cognitive behavioral treatment in adults living with overweight and obesity: a systematic review

Obesity is a chronic, complex, and multifactorial disease resulting from the interaction of genetic, environmental, and behavioral factors. It is characterized by excessive fat accumulation in adipose tissue, which damages health and deteriorates the quality of life. Although dietary treatment can significantly improve health, high attrition is a common problem in weight loss interventions with serious consequences for weight loss management and frustration. The strategy used to improve compliance has been combining dietary prescriptions and recommendations for physical activity with cognitive behavioral treatment (CBT) for weight management. This systematic review determined the dropout rate and predictive factors associated with dropout from CBT for adults with overweight and obesity. The data from the 37 articles selected shows an overall dropout rate between 5 and 62%. The predictive factors associated with attrition can be distinguished by demographics (younger age, educational status, unemployed status, and ethnicity) and psychological variables (greater expected 1-year Body Mass Index loss, previous weight loss attempts, perceiving more stress with dieting, weight and shape concerns, body image dissatisfaction, higher stress, anxiety, and depression). Common reasons for dropping out were objective (i.e., long-term sickness, acute illness, and pregnancy), logistical, poor job conditions or job difficulties, low level of organization, dissatisfaction with the initial results, lack of motivation, and lack of adherence. According to the Mixed Methods Appraisal quality analysis, 13.5% of articles were classified as five stars, and none received the lowest quality grade (1 star). The majority of articles were classified as 4 stars (46%). At least 50% of the selected articles exhibited a high risk of bias. The domain characterized by a higher level of bias was that of randomization, with more than 60% of the articles having a high risk of bias. The high risk of bias in these articles can probably depend on the type of study design, which, in most cases, was observational and non-randomized. These findings demonstrate that CBT could be a promising approach for obesity treatment, achieving, in most cases, lower dropout rates than other non-behavioral interventions. However, more studies should be conducted to compare obesity treatment strategies, as there is heterogeneity in the dropout assessment and the population studied. Ultimately, gaining a deeper understanding of the comparative effectiveness of these treatment strategies is of great value to patients, clinicians, and healthcare policymakers. Systematic review registration: PROSPERO 2022 CRD42022369995 Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022369995.

Effectiveness of cognitive retraining intervention on weight loss and lifestyle-related behaviours among adults: A systematic review and meta-analysis

INTRODUCTION

The review explores the potential benefits of cognitive retraining interventions in improving healthy lifestyle-related behaviours, and its possible use as an alternative or complementary approach to traditional weight loss interventions.

METHOD

Studies were selected using different electronic databases (PubMed, Web of Science, Scopus, Embase), to identify RCTs published in the last 23 years on cognitive retraining interventions for weight loss. A total of 12 studies were finalized for systematic review and six for meta-analysis based on the inclusion criteria. The risk of bias was assessed by the two reviewers independently using the criteria outlined in the Joanna Briggs Institute Critical Appraisal Tool for RCTs. The R software was used to perform meta-analysis.

RESULT

The overall effect estimates slightly favoured the intervention group, with a standardised mean difference (SMD) of -0.26 [95% CI (-0.58- 0.06) P < 0.05; I2 = 0.00%]. This suggests that although the effect was not statistically significant, cognitive retraining interventions may have a small effect on weight loss. The findings of the systematic review revealed that cognitive retraining interventions may be effective in modifying lifestyle behaviours and these changes may contribute in achieving and maintaining weight loss in the long run.

CONCLUSION

Interventions exhibited a positive effect on weight loss. These interventions demonstrated promise in modifying lifestyle behaviours, suggesting a potential role in achieving and sustaining long-term weight loss. Further research is warranted to refine and validate these findings.

Supplementing a widely available weight loss program with gamified inhibitory control training: A randomized pilot study

Background

Increasing evidence suggests that targeting self-regulatory processes may improve obesity treatment outcomes. Incorporating gamification principles in inhibitory control training may promote sustained training adherence and resulting benefits. This pilot study evaluated the preliminary efficacy of supplementing an evidence-based weight management program (WW) with sustained gamified inhibitory control training (PolyRules!) on change in Body Mass Index (BMI) among adults with overweight/obesity.

Methods

30 adults with overweight/obesity (M age 49.9 ± 12.4, 86.7% female; 23.3% Hispanic, mean BMI 35.3 ± 6.3) were randomly assigned to receive WW with or without PolyRules! for 12 weeks. The primary outcome was change in BMI from baseline to post-intervention across study arms. Implementation and process indicators were captured to inform larger trials.

Results

Average change in BMI was -0.9 in the WW arm and -1.2 in the WW + PolyRules! arm (Cohen's d = 0.26). In the WW + PolyRules! arm, increased training was associated with greater decreases in BMI (r = -0.506, p = 0.0454). WW + PolyRules! participants completed an average of 60.4% sessions and reported positive experiences. There was no difference in frequency of food (d = -0.02) and weight tracking (d = -0.19) between arms.

Conclusions

Studies in larger samples should evaluate training-related effects on weight. Supplementing WW with gamified inhibitory training appears feasible, with no detrimental effect on engagement.

The critical issue linking lipids and inflammation: Clinical utility of stopping oxidative stress

The formation of an atheroma begins when lipoproteins become trapped in the intima. Entrapped lipoproteins become oxidized and activate the innate immune system. This immunity represents the primary association between lipids and inflammation. When the trapping continues, the link between lipids and inflammation becomes chronic and detrimental, resulting in atherosclerosis. When entrapment ceases, the association between lipids and inflammation is temporary and healthy, and the atherogenic process halts. Therefore, the link between lipids and inflammation depends upon lipoprotein retention in the intima. The entrapment is due to electrostatic forces uniting apolipoprotein B to polysaccharide chains on intimal proteoglycans. The genetic transformation of contractile smooth muscle cells in the media into migratory secretory smooth muscle cells produces the intimal proteoglycans. The protein, platelet-derived growth factor produced by activated platelets, is the primary stimulus for this genetic change. Oxidative stress is the main stimulus to activate platelets. Therefore, minimizing oxidative stress would significantly reduce the retention of lipoproteins. Less entrapment decreases the association between lipids and inflammation. More importantly, it would halt atherogenesis. This review will analyze oxidative stress as the critical link between lipids, inflammation, and the pathogenesis of atherosclerosis. Through this perspective, we will discuss stopping oxidative stress to disrupt a harmful association between lipids and inflammation. Numerous therapeutic options will be discussed to mitigate oxidative stress. This paper will add a new meaning to the Morse code distress signal SOS-stopping oxidative stress.

Dietary intakes among people with vs without food addiction: A systematic review and meta-analysis

BACKGROUND & AIMS

Individuals with food addiction (FA) may experience addictive behaviours like those observed in other substances of abuse, which may affect their dietary intake habits. In fact, previous studies have reported associations between FA and dietary patterns, but this evidence has not been quantitatively summarised before. Therefore, this study aimed to explore differences in dietary intakes among adults with vs without food addiction.

METHODS

A systematic-review and meta-analysis was conducted. Interventional or observational studies evaluating dietary intakes associated with FA that used the Yale Food Addiction Scale (YFAS) were explored. PubMed, WoS and SCOPUS databases were searched up to September 2021, and selected articles were confirmed manually. Potentially eligible studies were checked independently by two researchers. YFAS and dietary habits were obtained from the studies selected by the search protocol. Standardized mean differences were retrieved and random effects meta-analyses were used for those studies reporting quantitative data.

RESULTS

From 162 potentially appropriate studies, 16 studies were finally included, all of which used cross-sectional designs. FA was generally related to higher intakes of total fat, proteins, sugar, and processed/energy-dense foods. The meta-analysis revealed that this association was only statistically significant in overweighted/obese individuals (P < 0.001 in all cases), while in those studies that included the general population (all weight categories), this association was not evident (p = 0.18).

CONCLUSIONS

Being addicted to food was not associated with a higher energy intake in the general population. However, among those with overweight or obesity, FA was associated with higher energy and nutrient consumption. This provides evidence on the influence of addictive behaviours on dietary intake patterns of people with excess body weight and reinforces the concept of food addiction and its influence in the development of obesity.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42020212866.

The additive effects of exercise and essential amino acid on muscle mass and strength in community-dwelling older Japanese women with muscle mass decline, but not weakness and slowness: a randomized controlled and placebo trial

BACKGROUND

Exercise and essential amino acid supplementation have been separately shown to improve muscle mass in elderly people, however, the combined, added effects of both interventions have yielded inconsistent results on muscle mass, strength, and physical function improvement.

AIMS

To investigate the additive effects of exercise and essential amino acid supplementation on muscle mass, strength, and walking ability in older Japanese women with muscle mass decline, but not weakness and slowness.

METHODS

One hundred thirty women over 65 years of age were defined as having muscle decline and randomly assigned into two groups; exercise and amino acid supplementation (n = 65) or exercise and placebo supplementation (n = 65). The exercise group attended a 60-min comprehensive training program once a week and were encouraged to perform a home-based exercise program. The amino acid or placebo group ingested a 3 g supplement daily for 3-month. Body composition was determined by bioelectrical impedance analysis. Interview data and functional fitness measurements, such as muscle strength and walking ability were collected at baseline and after the 3-month intervention.

RESULTS

There were no significant group × time interactions in primary outcomes such as muscle mass and strength. However, interactions were observed in the degree of low back discomfort (P = 0.014). Percent change of low back discomfort was significantly greater in exercise + amino acid group compared with exercise + placebo group.

CONCLUSIONS

The combination of exercise and amino acid supplementation had a beneficial effect on low back discomfort. However, additional effects were not observed in primary outcomes including muscle mass and strength in this population.

Effect of glucose and sucrose on cognition in healthy humans: a systematic review and meta-analysis of interventional studies

CONTEXT

Evidence suggests that plasma glucose levels may influence cognitive performance, but this has not been systematically reviewed and quantified.

OBJECTIVE

The aim of this review was to investigate the potential effects of glucose and sucrose, compared with placebo, on cognition in healthy humans.

DATA SOURCES

The electronic databases PubMed and Web of Science were searched up to December 2019. Reference lists of selected articles were checked manually.

STUDY SELECTION

Randomized controlled trials or crossover trials that compared glucose or sucrose with placebo for effects on cognition were eligible.

DATA EXTRACTION

Potentially eligible articles were selected independently by 2 authors. Risk of bias was assessed through the Cochrane Collaboration tool. Standardized mean differences (SMDs) were obtained from random-effects meta-analyses for a subsample of studies that reported the same outcomes.

RESULTS

Thirty-seven trials were identified, of which 35 investigated the effect of glucose consumption compared with placebo on cognition. Two studies found no effect of glucose on cognition, while the others found mixed results. Only 3 of the 37 studies investigated the effects of sucrose intake, reporting mixed results. Meta-analyses revealed a significantly positive effect of glucose compared with control, but only when a verbal performance test (immediate word recall) was used in parallel-design studies (SMD = 0.61; 95%CI, 0.20-1.02; I2 = 0%). Twenty-four studies were classified as having high risk of bias for the selection procedure.

CONCLUSIONS

A limited body of evidence shows a beneficial effect of glucose in individuals performing immediate verbal tasks. High-quality trials with standardized cognitive measurements are needed to better establish the effect of glucose or sucrose on cognition.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42019122939.

Executive Functions in Predicting Weight Loss and Obesity Indicators: A Meta-Analysis

While previous studies have suggested that there exists a relationship between obesity and executive function (EF), the mechanisms and causal relationship between them remain unclear. There are important clinical implications of determining whether EF can predict and treat obesity. We conducted a multilevel meta-analysis of randomized controlled trials (RCTs) and longitudinal studies. Specifically, we investigate (a) whether EF interventions have an effect on weight loss, (b) whether baseline EF can be a predictor of future weight loss through obesity intervention, and (c) whether early-life EF can predict future weight loss. Eight RCTs and 17 longitudinal studies with a total of 11,393 participants were identified. We found that (a) EF interventions may not have an effect on weight loss, (b) baseline inhibition (β = 0.259, p = 0.03) and delay discounting (β = −0.17, p = 0.04) significantly predict future weight loss through obesity intervention, (c) age (F = 13.666, p = 0.005) moderates the relationship between working memory and weight loss through intervention, but not weight status, type of intervention, and percentage of female, and (d) early life inhibition (β = 0.185, p = 0.07) is a marginally significant predictor of future weight loss. Our results seem to support the assumption that the relationship between EF and obesity is not direct, and a higher-order factor, such as genes, may link obesity and EF. Building on the preliminary findings, further studies focusing on EF and obesity are needed in the future.

Moderate Weight Loss Modifies Leptin and Ghrelin Synthesis Rhythms but Not the Subjective Sensations of Appetite in Obesity Patients

Obesity is characterized by a resistance to appetite-regulating hormones, leading to a misalignment between the physiological signals and the perceived hunger/satiety signal. A disruption of the synthesis rhythm may explain this situation. The aim of this study was to evaluate the effect of dietary-induced weight loss on the daily rhythms of leptin and ghrelin and its influence on the daily variability of the appetite sensations of patients with obesity. Twenty subjects with obesity underwent a hypocaloric dietary intervention for 12 weeks. Plasma leptin and ghrelin were analyzed at baseline and at the end of the intervention and in 13 normal-weight controls. Appetite ratings were analyzed. Weight loss decreased leptin synthesis (pauc < 0.001) but not the rhythm characteristics, except the mean variability value (pmesor = 0.020). By contrast, the mean ghrelin level increased after weight loss. The rhythm characteristics were also modified until a rhythm similar to the normal-weight subjects was reached. The amount of variability of leptin and ghrelin was correlated with the effectiveness of the dietary intervention (p < 0.020 and p < 0.001, respectively). Losing weight partially restores the daily rhythms of leptin and modifies the ghrelin rhythms, but appetite sensations are barely modified, thus confirming that these hormones cannot exercise their physiological function properly.