Screen time and the risk of metabolic syndrome among children and adolescents: A systematic review and dose-response meta-analysis.

AIMS: The metabolic syndrome (MetS) and its consequences are one of the main public health challenges worldwide. We conducted a systematic review and dose-response meta-analysis of studies that examined the association between screen time and the MetS among children and adolescents. DATA SYNTHESIS: A systematic search was conducted using electronic databases, including PubMed, Scopus, ProQuest, and Cochrane Library, for studies published from 1963 up to 2 May 2022. In this systematic review and meta-analysis, observational studies with cross-sectional, case-control, and cohort design evaluating the association between screen time and MetS were included. Random effects models and linear and nonlinear dose-response meta-analyses were used to pool study results. RESULTS: Seven studies were included in the meta-analysis. The summary OR of MetS among children and adolescents for the highest vs. lowest time of screen time was 1.64 (95% CI: 1.32-2.03, with little evidence of heterogeneity, I2 = 9.3%, P-heterogeneity = 0.35, n = 7 studies) and 1.64 (95% CI: 1.27-2.12, I2 = 27.7%, n = 6) for cross-sectional studies. Results persisted across several additional subgroup analyses. There was a linear positive association between screen time and the risk of MetS (P dose-response <0.0001; P nonlinearity = 0.64) with an OR of 1.29 (95% CI: 1.12-1.46) per 2 h/day increment in screen time. CONCLUSION: The current dose-response meta-analysis suggested that increased screen time is associated with an increased risk of MetS among children and adolescents. Public health strategies may target unhealthy screen-based related behaviors to halt the development of MetS among children and adolescents.

CARDIO-RENAL METABOLIC SYNDROME AND PRO-INFLAMMATORY FACTORS: THE DIFFERENTIAL EFFECTS OF DIETARY CARBOHYDRATE AND FAT.

BACKGROUND: We aimed to evaluate whether a high carbohydrate or a high fat diet differs in alteration of the inflammatory and metabolic risk factors in cardio-renal metabolic syndrome in rats. METHODS: Twelve male Wister rats were randomly divided into two groups: one received diet 1 standard pellet rat diet (D1) containing 10% fat, 50% carbohydrate, 25% protein and another group received diet 2 (D2) containing 59% fat, 30% carbohydrate and 11% protein for 16 weeks. Weight was recorded weekly. FSG and insulin levels were measured using an enzymatic spectrophotometric and a standard ELISA kit respectively. Inflammatory parameters including TGF-ß, MCP-1, TNF-α, IL-1ß, IL-6 in the renal and cardiac tissues of rats were evaluated by ELISA technique. RESULT: Food intake in D1 and D2 groups increased in the study period, however food intake in D2 group was significantly higher compared with D1 group. FSG, HOMA and TG concentrations in D2 group were significantly higher compared to D1 group. Moreover, TGF-ß and MCP-1 concentrations in the renal tissues of D2 group and TNF-α in the cardiac tissues of D1 group were significantly higher compared with D1 group (P<0.05). Positive associations between IL-1ß and TG and between HOMA, FSG with TGF-ß and MCP-1 in the renal tissue of animals were also identified.

The effectiveness of theory- and model-based lifestyle interventions on HbA1c among patients with type 2 diabetes: a systematic review and meta-analysis.

OBJECTIVES: The prevalence of type 2 diabetes is rising rapidly around the world. A number of systematic reviews have provided evidence for the effectiveness of lifestyle interventions on diabetic patients. The effectiveness of theory- and model-based education-lifestyle interventions for diabetic patients are unclear. The systematic review and meta-analysis aimed to evaluate and quantify the impact of theory-based lifestyle interventions on type 2 diabetes. STUDY DESIGN: A literature search of authentic electronic resources including PubMed, Scopus, and Cochrane collaboration was performed to identify published papers between January 2002 and July 2016. METHODS: The PICOs (participants, intervention, comparison, and outcomes) elements were used for the selection of studies to meet the inclusion and exclusion criteria. Mean differences and standard deviations of hemoglobin A1c (HbA1c [mmol/mol]) level in baseline and follow-up measures of studies in intervention and control groups were considered for data synthesis. A random-effects model was used for estimating pooled effect sizes. To investigate the source of heterogeneity, predefined subgroup analyses were performed using trial duration, baseline HbA1c (mmol/mol) level, and the age of participants. Meta-regression was performed to examine the contribution of trial duration, baseline HbA1c (mmol/mol) level, the age of participants, and mean differences of HbA1c (mmol/mol) level. The significant level was considered P < 0.05. RESULTS: Eighteen studies with 2384 participants met the inclusion criteria. The pooled main outcomes by random-effects model showed significant improvements in HbA1c (mmol/mol) -5.35% (95% confidence interval = -6.3, -4.40; P < 0.001) with the evidence of heterogeneity across studies. CONCLUSION: The findings of this meta-analysis suggest that theory- and model-based lifestyle interventions have positive effects on HbA1c (mmol/mol) indices in patients with type 2 diabetes. Health education theories have been applied as a useful tool for lifestyle change among people with type 2 diabetes.

Vitamin D administration, cognitive function, BBB permeability and neuroinflammatory factors in high-fat diet-induced obese rats.

OBJECTIVES: The purpose of this research was to investigate the effects of vitamin D administration on cognitive function, nuclear factor-κB (NF-κB), brain-derived neurotrophic factor (BDNF) concentration in the hippocampus and blood-brain barrier (BBB) permeability in high-fat diet (HFD)-induced obese rats. METHODS: Male Wistar rats were fed either a control diet or HFD for 16 weeks (n=20); then, each group was randomized into two subgroups supplemented orally with 500 IU kg-1 vitamin D for 5 weeks. A Morris water maze (MWM) test was performed at the 21st week to examine cognitive function. BBB permeability was characterized by Evans blue dye in the hippocampus. BDNF and NF-κB concentrations in the hippocampus and serum vitamin D concentrations were also measured. RESULTS: HFD led to a significant delay in escape latency time and reduced time of MWM probe test because of increased NF-κB and decreased BDNF concentrations in the hippocampus. Vitamin D supplementation in the HFD group significantly reduced body weight, NF-κB concentrations, BBB permeability and increased BDNF concentrations in the hippocampus. CONCLUSIONS: Vitamin D reversed HFD-induced cognitive impairments by reduction of the NF-κB and elevation of BDNF concentrations and modulation of the BBB permeability in rats' hippocampus.

An interactive web-based intervention on nutritional status, physical activity and health-related quality of life in patient with metabolic syndrome: a randomized-controlled trial (The Red Ruby Study).

BACKGROUND/OBJECTIVES: Physical inactivity and unhealthy nutritional behaviors are recognized as the key factors in the cause and management of metabolic syndrome (MetS). The effectiveness of interactive web-based interventions on dietary intakes, physical activity and health-related quality of life (HRQOL) among people with MetS is currently unknown. METHODS: The two-arm randomized-controlled trial was conducted for patients with MetS from June through December 2012 in Tehran, Iran. Participants (n=160) were recruited through online registration on the study website. After free clinical assessments of eligible participants for MetS, they were randomly assigned to intervention and control groups (n=80). All participants received general information about cardiovascular diseases and MetS risk factors via the website. The intervention group logged in to interactive part including My Healthy Heart Profile, received tailored calorie-restricted diet and used all parts of the interactive prevention program. Anthropometric measures, glycemic status, lipid profile, physical activity and food intake were evaluated at the beginning and after 6-month follow-up. HRQOL was assessed at beginning, 3- and 6-month follow-up. RESULTS: There were no significant differences between the intervention and control groups on age, gender, education and MetS factors. In comparison with control group, the intervention group showed significant changes in moderate physical activity 260.3±473.6 vs 101.6±213.1 MET-min/week, walking 505.2±505.3 vs 321±884 MET-min per week, cholesterol intake -88.4±158.7 vs -8.3±6 mg per day, total calories -430.2±957.5 vs -392.9±34.7 kcal per day and sodium 1336.9±2467 vs 1342±3200.4 mmol per day. With regard to HRQOL, the intervention group showed greater improvement in general health and vitality (P<0.05 for all). CONCLUSION: These results indicate the positive impact of a lifestyle intervention by a web-based program on physical activity, dietary intake and several dimension of QoL. The use of web-based approaches is a great interest to manage patients at high cardiovascular risk, especially where the prevalence of obesity, MetS and diabetes is increasing.