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To investigate the role of potential shared mediators in the association of TV-viewing and frequency of ultra-processed food consumption with anxiety-induced sleep disturbance.
Data from the Adolescent School-based Health Survey, a Brazilian nationally representative survey of 9th grade adolescents conducted in 2015 were used.
99,791 adolescents (52,015 girls) with a mean age of 14.3 years (range: 11–19 years) participated. All variables were collected through a self-reported questionnaire based on the Global School-based Student Health Survey. Anxiety-induced sleep disturbance was the outcome. More than 4h/day of TV-viewing and daily consumption of ultra-processed foods were the exposures. Body satisfaction, loneliness, self-rated health and eating while watching TV or studying were mediators. Age, ethnicity, food insecurity, type of city (capital or interior), country region, and physical activity were covariates. Logistic regression and mediation models (Karlsson-Holm-Breen method) assessed associations.
Both daily ultra-processed food consumption [boys:OR:1.48(95%CI:1.30-1.70); girls:1.46(1.34-1.60)] and TV-viewing [boys:1.24(1.08-1.43); girls:1.09(1.00-1.19)] were associated with higher odds for anxiety-induced sleep disturbance. Loneliness and eating while watching TV or studying consistently mediated the association of both daily ultra-processed food consumption (loneliness: boys: 17.4%, girls: 23.4%; eat while watching TV or studying: girls: 6.8%) and TV-viewing (loneliness: boys: 22.9%, girls: 45.8%; eat while watching TV or studying: boys: 6.7%, girls: 17.9%) with anxiety-induced sleep disturbance.
Daily ultra-processed food consumption and TV-viewing share mediators and can act in synergic mechanisms in the association with anxiety-induced sleep disturbance. Therefore, future interventions should focus in the reduction of both behaviors in combination.
Our aim was to analyse the association of change patterns on TV-viewing and computer/tablet use and incidence of elevated consumption of ultra-processed food consumption and lower consumption of fruits and vegetables during the COVID-19 pandemic.
Data of 39 208 Brazilian adults from a Behaviour Web Survey were used. Unhealthy nutrition habits were eating fruits or vegetables for <5 d/week and ultra-processed food (sugary foods, snacks, ready-to-eat frozen foods and embedded foods) for ≥5 d/week. For incidence indicators, we only considered participants without unhealthy behaviour before the quarantine. We created four categories of change in TV-viewing and computer/tablet use, considering a cut-off point of 4 h/d for each behaviour (1 – consistently low, 2 – become low during the quarantine, 3 – become high during the quarantine or 4 – consistently high). Analyses were adjusted for sex, age group, highest academic achievement, per capita income, working status during the quarantine, skin colour and adherence to the quarantine.
Brazilian adults (nationally representative).
Logistic regression models revealed that high TV-viewing and computer/tablet use incidence were associated with higher odds for elevated frequency of ultra-processed food consumption (TV-viewing: OR 1·70; 95 % CI 1·37, 2·12; computer/tablet: OR 1·73; 95 % CI 1·31, 2·27) and low consumption of fruit and vegetables (TV-viewing: OR 1·70; 95 % CI 1·29, 2·23; computer/tablet: OR 1·53; 95 % CI 1·08, 2·17) incidence. Consistent high computer/tablet use also presented higher odds for incidence of elevated frequency of ultra-processed food consumption.
Participants with incidence of sedentary behaviours were also more likely to present incidence of unhealthy diet during the COVID-19 pandemic quarantine.
To analyse the relationship between different heart rate variability indices, resting heart rate, and cardiovascular markers in adolescents.
A cross-sectional study was carried out with information from an ongoing cohort study. The sample was composed of 99 adolescents who complied with the following inclusion criteria: aged between 11 and 14 years; enrolled in a school unit of elementary education; absence of any known diseases; no drug consumption; and a formal consent signed by the parents or legal guardians. Weight, height, heart rate variability, lipid profile, inflammatory markers, blood pressure, resting heart rate, intima-media thickness, blood flow, and trunk fatness were measured. Partial correlation and linear regression (expressed by β and 95% confidence intervals [95%CI]) analyses were used to analyse the relationships between the variables.
In the linear regression analysis, even after adjustments for sex, age, trunk fatness, and somatic maturation, parasympathetic activity presented significant correlations with maximum carotid artery blood flow (β=−0.111 [95%CI=−0.216; −0.007]), systolic blood pressure (β=−0.319 [95%CI=−0.638; −0.001]), and resting heat rate (β=−0.005 [95%CI=−0.009; −0.002]).
Parasympathetic activity at rest is inversely related to maximum and minimum blood flow, triacylglycerol levels, and systolic blood pressure. These findings suggest that heart rate variability has the potential to discriminate pre-pubertal adolescents at increased risk.
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