Impact of a diabetes prevention program on body size, physical activity, and diet among Kanien'keha:ka (Mohawk) children 6 to 11 years old: 8-year results from the Kahnawake Schools Diabetes Prevention Project

OBJECTIVES

Report the 8-year impact on body size, physical activity, and diet of a community-based diabetes prevention program for elementary-school children in a Kanien'keha:ka (Mohawk) community in Canada.

METHODS

Follow-up (1994-1996) of subjects in the intervention and comparison community and repeat cross-sectional measurements in the intervention community alone from 1994 to 2002. Measures included triceps and subscapular skinfold thicknesses, body mass index (BMI), weekly number of 15-minute episodes of physical activity, run/walk test times, television watching, and consumption of sugared foods, fatty foods, and fruits and vegetables.

RESULTS

The longitudinal data of 1994-1996 showed some early positive effects of the program on skinfold thickness but not on BMI, physical activity, fitness, or diet. Repeat cross-sectional measures from 1994 to 2002 showed increases in skinfold thickness and BMI. Physical activity, fitness, and television watching showed favorable trends from 1994 to 1999 that were not sustained in 2002. Key high-fat and high-sugar foods consumption decreased, as did consumption of fruits and vegetables.

CONCLUSIONS

Although early results showed some successes in reducing risk factors for type 2 diabetes, these benefits were not maintained over 8 years.

Who succeeds in maintaining weight loss? A conceptual review of factors associated with weight loss maintenance and weight regain

Weight loss is difficult to achieve and maintaining the weight loss is an even greater challenge. The identification of factors associated with weight loss maintenance can enhance our understanding for the behaviours and prerequisites that are crucial in sustaining a lowered body weight. In this paper we have reviewed the literature on factors associated with weight loss maintenance and weight regain. We have used a definition of weight maintenance implying intentional weight loss that has subsequently been maintained for at least 6 months. According to our review, successful weight maintenance is associated with more initial weight loss, reaching a self-determined goal weight, having a physically active lifestyle, a regular meal rhythm including breakfast and healthier eating, control of over-eating and self-monitoring of behaviours. Weight maintenance is further associated with an internal motivation to lose weight, social support, better coping strategies and ability to handle life stress, self-efficacy, autonomy, assuming responsibility in life, and overall more psychological strength and stability. Factors that may pose a risk for weight regain include a history of weight cycling, disinhibited eating, binge eating, more hunger, eating in response to negative emotions and stress, and more passive reactions to problems.

The Wenckebach phenomenon

Background

The introduction of new medical technologies such as sensors has accelerated the process of collecting patient data for relevant clinical decisions, which has led to the introduction of a new technology known as digital biomarkers.

Objective

This study aims to assess the methodological quality and quality of evidence from meta-analyses of digital biomarker–based interventions.

Methods

This study follows the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guideline for reporting systematic reviews, including original English publications of systematic reviews reporting meta-analyses of clinical outcomes (efficacy and safety endpoints) of digital biomarker–based interventions compared with alternative interventions without digital biomarkers. Imaging or other technologies that do not measure objective physiological or behavioral data were excluded from this study. A literature search of PubMed and the Cochrane Library was conducted, limited to 2019-2020. The quality of the methodology and evidence synthesis of the meta-analyses were assessed using AMSTAR-2 (A Measurement Tool to Assess Systematic Reviews 2) and GRADE (Grading of Recommendations, Assessment, Development, and Evaluations), respectively. This study was funded by the National Research, Development and Innovation Fund of Hungary.

Results

A total of 25 studies with 91 reported outcomes were included in the final analysis; 1 (4%), 1 (4%), and 23 (92%) studies had high, low, and critically low methodologic quality, respectively. As many as 6 clinical outcomes (7%) had high-quality evidence and 80 outcomes (88%) had moderate-quality evidence; 5 outcomes (5%) were rated with a low level of certainty, mainly due to risk of bias (85/91, 93%), inconsistency (27/91, 30%), and imprecision (27/91, 30%). There is high-quality evidence of improvements in mortality, transplant risk, cardiac arrhythmia detection, and stroke incidence with cardiac devices, albeit with low reporting quality. High-quality reviews of pedometers reported moderate-quality evidence, including effects on physical activity and BMI. No reports with high-quality evidence and high methodological quality were found.

Conclusions

Researchers in this field should consider the AMSTAR-2 criteria and GRADE to produce high-quality studies in the future. In addition, patients, clinicians, and policymakers are advised to consider the results of this study before making clinical decisions regarding digital biomarkers to be informed of the degree of certainty of the various interventions investigated in this study. The results of this study should be considered with its limitations, such as the narrow time frame.

International Registered Report Identifier (IRRID)

RR2-10.2196/28204

In vitro killing of schistosomula of Schistosoma mansoni by BCG and C. parvum-activated macrophages

Resistance to Schistosoma mansoni infection in the mouse has been induced either specifically by a primary infection with this parasite or nonspecifically by a variety of immunostimulants such as BCG. In the present study we developed an in vitro system to examine the effector mechanism of nonspecifically induced resistance. Activated macrophage monolayers obtained from BCG- or Corynebacterium parvum treated mice killed a respective mean 32 +/- 6% and 48 +/- 5% of schistosomula after 24 hr incubation. The killing of the parasites was verified by their inability to mature to adult worms upon injection into normal mice. The activated macrophage-mediated killing was related to cell:parasite ratio, and was partially lost if the macrophage monolayers were kept in cultures for 24 hr before incubation with the organism. Supernatants of macrophages cultured in the presence of schistosomula killed a mean of 51 +/- 3% of the organisms whereas those from cells cultured alone resulted in a mean killing of 25 +/- 3%. Furthermore, toxic supernatants could be generated equally well on incubation with S. mansoni schistosomula or Trichinella spiralis larvae. Our data show that activated macrophage monolayers through soluble mediators destroy a significant proportion of the multicellular parasite S. mansoni schistosomula in vitro.

[François Lepage (1905--1978)]

Background

Overweight and obesity have been linked to several serious health problems and medical conditions. With more than a quarter of the young population having weight problems, the impacts of overweight and obesity on this age group are particularly critical. Mobile health (mHealth) apps that support and encourage positive health behaviors have the potential to achieve better health outcomes. These apps represent a unique opportunity for young people (age range 10-24 years), for whom mobile phones are an indispensable part of their everyday living. However, despite the potential of mHealth apps for improved engagement in health interventions, user adherence to these health interventions in the long term is low.

Objective

The aims of this research were to (1) review and analyze mHealth apps targeting obesity and overweight and (2) propose guidelines for the inclusion of user interface design patterns (UIDPs) in the development of mHealth apps for obese young people that maximizes the impact and retention of behavior change techniques (BCTs).

Methods

A search for apps was conducted in Google Play Store using the following search string: [“best weight loss app for obese teens 2020”] OR [“obesity applications for teens”] OR [“popular weight loss applications”]. The most popular apps available in both Google Play and Apple App Store that fulfilled the requirements within the inclusion criteria were selected for further analysis. The designs of 17 mHealth apps were analyzed for the inclusion of BCTs supported by various UIDPs. Based on the results of the analysis, BCT-UI design guidelines were developed. The usability of the guidelines was presented using a prototype app.

Results

The results of our analysis showed that only half of the BCTs are implemented in the reviewed apps, with a subset of those BCTs being supported by UIDPs. Based on these findings, we propose design guidelines that associate the BCTs with UIDPs. The focus of our guidelines is the implementation of BCTs using design patterns that are impactful for the young people demographics. The UIDPs are classified into 6 categories, with each BCT having one or more design patterns appropriate for its implementation. The applicability of the proposed guidelines is presented by mock-ups of the mHealth app “Morphe,” intended for young people (age range 10-24 years). The presented use cases showcase the 5 main functionalities of Morphe: learn, challenge, statistics, social interaction, and settings.

Conclusions

The app analysis results showed that the implementation of BCTs using UIDPs is underutilized. The purposed guidelines will help developers in designing mHealth apps for young people that are easy to use and support behavior change. Future steps involve the development and deployment of the Morphe app and the validation of its usability and effectiveness.