Transtheoretical model for change in obese adolescents: MERC randomized clinical trial

The Effect of a Physical Activity Program Using WhatsApp on Adolescents' Exercise Behavior

This study aims to demonstrate the effect of a transtheoretical model (TTM)-based physical activity program on the exercise behavior of adolescents using WhatsApp. The study was conducted with high school students (N = 185) in a pre-/posttest, quasi-experimental design. TTM-based text messages were sent to the intervention group (n = 95) over WhatsApp every day for 8 weeks. The intervention group demonstrated more statistically significant progression in the exercising stages of change compared to the control group (n = 90) (χ2 = 20.10; p = .00). It was also found that this group had a higher exercising self-efficacy score (t = 2.647; p = .009) and a higher physical activity total metabolic equivalent of task score (Z = -3.521; p = .000). There was no significant difference in BMI and perception of pros and cons (p > .05). The program was found to be effective in terms of recording progress in the exercising stages of change, increasing exercising self-efficacy, and maintaining a physical activity program.

Impact of sports participation on components of metabolic syndrome in adolescents: ABCD growth study

OBJECTIVES

This study aimed to analyze the impact of sports participation (12 months of practice) on the components of metabolic syndrome (MetS) in both sexes.

METHODS

This is an observational longitudinal study, a part of which is entitled "Analysis of Behaviors of Children During Growth" (ABCD Growth Study), Presidente Prudente, São Paulo, Brazil. The sample was composed of 171 adolescents (112 boys and 59 girls), divided into non-sports and sports groups. High-density lipoprotein-cholesterol (HDL-c), triglycerides, and glucose were analyzed by the colorimetric method of dry chemistry and processed biochemically. Systolic blood pressure and diastolic blood pressure were measured using an automatic device. Body fat was estimated using a densitometry scanner.

RESULTS

Adolescents who practiced sports were younger (p-value=0.001) and had a lower peak height velocity (p-value=0.001) than the non-sports group. The differences (Δ) after 12 months were of greater magnitude for the sports group when compared to the non-sports group (p-value=0.013), glucose (moderate magnitude in favor of the sports group; p-value=0.001), HDL-c (small magnitude in favor of the sports group; p-value=0.0015), and MetS (moderate magnitude in favor of the sports group; p-value=0.001).

CONCLUSIONS

The practice of sports in adolescents had a protective effect on the metabolic components of MetS.

Transtheoretical model-based nutritional interventions in adolescents: a systematic review

BACKGROUND

Literature has shown a tendency of inadequate dietary intake among youth, consequently, nutritional interventions are required. The transtheoretical model (TTM) classifies individuals based on their readiness to change. This model is widely used for health education interventions with proven efficacy.

PURPOSE

This review aimed to weigh the strength of evidence about the TTM usage in nutritional interventions for adolescents and its effectiveness regarding dietary intake.

METHODS

This study followed the PRISMA guidelines. Eligible studies were input into Mendeley software. The Adolec, Google Scholar, LILACS, PsycINFO, PubMed, Science Direct and Web of Science databases were searched. Only full original articles written in English, Spanish or Portuguese on randomized controlled trials and quasi-experimental designs that applied the TTM in the design of nutritional interventions targeting adolescents were included, with no restrictions on publication date. The quality and risk of bias was evaluated with the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies.

RESULTS

The initial search yielded 3779 results. Three studies were rated as strong, six as moderate and five as weak. The final sample of 14 articles included adolescents that were mostly recruited from schools, with interventions ranging from one month to three years. The TTM was used alone or combined with other behavior-change theories and most of the interventions involved digital technology. The nutritional topics covered included fruit and vegetable consumption, low-fat diet, and cooking skills. Four studies presented improvement in fruit and vegetable consumption and four progressed through stages of change. Participants from two interventions reduced fat intake. At the end of one intervention, all the participants were in action and maintenance stages.

CONCLUSION

The TTM seems to be a successful strategy for nutritional intervention aiming at improving dietary intake in adolescents. Its application in different contexts shows that the TTM is flexible and possible to be implemented in many settings. The use of the model is shown to be restricted to the stage of change' construct. Further studies should use all constructs of the TTM in the design and compare the TTM with other behavior-change theories to better understand its effectiveness.

How is obesity associated with happiness? Evidence from China

Happiness is a universal goal that people pursue. Studies of the relationship between obesity and happiness have shown mixed findings. It is uncertain whether an optimum BMI level exists and at what level obesity interferes or interacts with happiness. Guided by the Circle of Discontent Theory, we examined the relationship between obesity and happiness among Chinese residents using the 2014 China Family Panel Studies data. The results reveal an inverted U-shaped relationship between BMI and happiness, with obesity associated with happiness through physical appearance, health, and income. The socioeconomic conditions for the appropriate weight to achieve happiness are discussed.

Layperson-Led vs Professional-Led Behavioral Interventions for Weight Loss in Pediatric Obesity: A Systematic Review and Meta-analysis

IMPORTANCE

The appropriate approach for weight loss among children and adolescents with overweight and obesity remains unclear.

OBJECTIVE

To evaluate the difference in the treatment outcomes associated with behavioral weight loss interventions led by laypersons and professionals in comparison with unsupervised control arms among children and adolescents with overweight and obesity.

DATA SOURCES

For this systematic review and meta-analysis, the Medical Literature Analysis and Retrieval System Online (MEDLINE), Embase, the Cochrane Library, and Cumulative Index of Nursing and Allied Health Literature (CINAHL) databases were searched from January 1, 1996, to June 1, 2019.

STUDY SELECTION

Included in this study were randomized clinical trials (RCTs) of behavioral interventions lasting at least 12 weeks for children and adolescents (aged 5-18 years) with overweight and obesity. Exclusion criteria included non-RCT studies, interventions lasting less than 12 weeks, adult enrollment, participants with other medical diagnoses, pharmacological treatment use, and articles not written in English. Two of 6 reviewers independently screened all citations. Of 25 586 citations, after duplicate removal, 78 RCTs (5780 participants) met eligibility criteria.

DATA EXTRACTION AND SYNTHESIS

A bayesian framework and Markov chain Monte Carlo simulation methods were used to combine direct and indirect associations. Random-effects and fixed-effect network meta-analysis models were used with the preferred model chosen by comparing the deviance information criteria. This study was registered with the International Prospective Register of Systematic Reviews (PROSPERO) and followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.

MAIN OUTCOMES AND MEASURES

The immediate and sustained changes in weight and body mass index (BMI) standardized mean difference (SMD) were primary outcomes planned before data collection began, whereas waist circumference and percent body fat were secondary outcomes. The hypothesis being tested was formulated before the data collection.

RESULTS

Of 25 586 citations retrieved, we included 78 RCTs (5780 participants), with a follow-up of 12 to 104 weeks. Compared with the control condition, random-effects models revealed that professional-led weight loss interventions were associated with reductions in weight (mean difference [MD], -1.60 kg [95% CI, -2.30 to -0.99 kg]; 68 trials; P < .001) and BMI (SMD, -0.30 [95% CI, -0.39 to -0.20]; 59 trials; P < .001) that were not sustained long term (weight MD, -1.02 kg [95% CI, -2.20 to 0.34 kg]; 21 trials; P = .06; BMI SMD, -0.12 [95% CI, -0.46 to 0.21]; 20 trials; P < .001). There was no association between layperson-led interventions and weight loss in the short-term (MD, -1.40 kg [95% CI, -3.00 to 0.26 kg]; 5 trials; P = .05) or long-term (MD, -0.98 kg [95% CI, -3.60 to 1.80 kg]; 1 trial; P = .23) compared with standard care. No difference was found in head-to-head trials (professional vs layperson MD, -0.25 kg [95% CI -1.90 to 1.30 kg]; 5 trials; P = .38).

CONCLUSIONS AND RELEVANCE

This systematic review and meta-analysis found that professional-led weight loss interventions were associated with short-term but not sustained weight reduction among children and adolescents with overweight or obesity, and the evidence for layperson-led approaches was insufficient to draw firm conclusions.