Acceptability and use of waist-worn physical activity monitors in Jamaican adolescents: lessons from the field

OBJECTIVE

We report our experience with a validated waist-worn activity monitor in Jamaican adolescents attending urban high schools. Seventy-nine adolescents from the Global Diet and Activity Research (GDAR) study, recruited from 5 urban Jamaican high schools (two coeducational (n = 37), two all-female schools (n = 32) and one all-boys school (n = 10)) were asked to wear Actigraph wGT3X-BT accelerometers for 7 days (24-h), removing the device only when bathing or swimming. They also logged wake up and bed times in an activity diary. Accelerometry was considered valid if at least 4 days with ≥ 10-h monitor wear were recorded. Validity was compared by adolescent demographic and school characteristics. We also reviewed the students' written feedback on objective physical activity measurement.

RESULTS

Participants, 80.5% female, had a mean age of 15.5 ± 0.8 years with 60% attending schools in low-income communities. Accelerometer return rates were > 98% with 84% providing valid data. Validity did not vary by age group, sex and school setting. While participants were excited about participating in the accelerometer sub-study, commonly reported challenges included monitor discomfort during sleep and maintaining the study diary. Objective measurement of physical activity using 24-h waist-worn accelerometers is feasible and acceptable in Jamaican adolescents.

Use of green spaces, self-satisfaction and social contacts in adolescents: A population-based CASPIAN-V study

BACKGROUND

A growing body of evidence has associated contact with green spaces with improved mental health and wellbeing in adults. Social contacts has been postulated as a potential mechanism underlying such effects. However, the available evidence on the association between green spaces and self-satisfaction and also the mediatory role of social contacts in health benefits of green spaces in adolescents is still very scarce. We aimed to evaluate the association of time spent in different types of green spaces with self-satisfaction and social contacts in adolescents. We also investigated the mediatory role of social contacts in the association of green space use and self-satisfaction.

METHODS

This cross-sectional study was based on a population-representative sample of 10,856 adolescents (10-18 years old) living in urban and rural districts across 30 provinces of Iran (2015). Data on the time spent in green spaces (separately for parks, forests and private gardens), self-satisfaction, social contacts (number of friends and time spent with friends), and socio-demographic characteristics were obtained through questionnaires from parents and children. Logistic mixed effects models with recruitment centre as the random effect were developed to estimate associations adjusted for relevant covariates.

RESULTS

More time spent in green spaces was associated with improved self-satisfaction and social contacts. While for the self-satisfaction, there was no indication for effect modification by sex, socioeconomic status (SES), and urbanity, we observed stronger associations for older adolescents (> 14 years old). For social contacts, we found indications for stronger associations for boys, older adolescents, those residing in rural areas, and those from lowest and highest SES groups. Social contacts could explain more than half of the association between green spaces use and self-satisfaction.

CONCLUSIONS

Our observed enhanced self-satisfaction and social contacts associated with more time spent in green spaces could provide policymakers with measures to improve mental wellbeing of adolescents. Further studies are required to replicate our findings in other populations with different climates, cultures and lifestyles.

Association of parental obesity with cardiometabolic risk factors in their children: The CASPIAN-V study

BACKGROUND

The family environment has a crucial role in the development of childhood obesity and related cardiometabolic disorders. This study aims to investigate the association of parental obesity and cardiometabolic risk factors in their children.

METHODS

This multicentric cross-sectional study was performed on 14400 students (aged 7-18 years) and one of their parents. Students were recruited by multistage, stratified cluster sampling from urban and rural areas of 30 provinces of Iran. Fasting venous blood was obtained from a random sample of 4200 students. Demographic, anthropometric and clinical variables were collected.

RESULTS

Data of 14002 students and results of blood samples of 3483 of them were complete and included in the current study. The prevalence of obesity in children, fathers, and mothers was 11.4%, 10.6%, and 24.2%, respectively. In students, the most commonly observed metabolic abnormality was low HDL-C (29.5%); the prevalence of metabolic syndrome and dyslipidemia was 5% and 55.7%, respectively. Significant correlations were observed between the body mass index (BMI) and waist circumference of parents and weight, height, BMI, and waist circumference, as well as systolic and diastolic blood pressure (BP) of their children (P< 0.05). In the multivariate model, the risk of excess weight (OR: 1.30, 95%CI: 1.17-1.44), obesity (OR: 1.36, 95%CI: 1.18-1.59), abdominal obesity (OR: 1.16, 95%CI: 1.05-1.29) and elevated BP (OR: 1.17, 95%CI: 1.04-1.31) were higher in those students whose parents had excess weight compared with other students. Parental obesity did not have significant association with metabolic syndrome and dyslipidemia in their children.

CONCLUSIONS

Parental history of obesity could be used as a practical approach for the early preventive measures and identification of children at risk of cardiometabolic complications.

A Systematic Review on the Prevalence of Overweight and Obesity, in Iranian Children and Adolescents

Context

Obesity has now become a common health problem worldwide. To gain insight into the epidemiology of the problem in Iran, we systematically reviewed all available studies on the prevalence of overweight and obesity in the Iranian pediatric population.

Evidence Acquisition

We systematically searched PubMed, ISI, SCOPUS, as well as Iranmedex, Irandoc, and Scientific Information Database (SID) databases.All studies on mean and standard deviation or percentile categories of BMI, WC, WHR, or WHtR or prevalence of obesity/overweight in Iranian child and adolescence, were performed from January 1990 to the end of December 2013. Refining processes were conducted by two independent reviewers. Quality assessment and data extraction followed based on validated form. As, these data were heterogeneous, meta-analysis was not performed.

Results

From 3253 records, through three refining steps, 129 articles were found related to our study. In Iran, national studies are limited and nearly there is no comprehensive study for sub-national trends. Different age and sex groups had large variations in the prevalence of obesity and overweight (from 1% up to 16.1% and from 4.4% up to 42.3% respectively for obesity and overweight).

Conclusions

Related data are very scattered or limited to some specific subgroups in some living areas. For comparing, aggregating, and imputing the information we need more modern practical statistical methods.

A Systematic Review of Studies on Blood Pressure in Iranian Pediatric Population: First Report From the Middle East and North Africa

Context:

Blood pressure (BP) tracks from childhood to adulthood, and has ethnic variations. Therefore, it is important to assess the situation of pediatric BP in different populations. This study aims to systematically review the studies conducted on BP in Iranian children and adolescents.

Evidence Acquisition:

We conducted a systematic review on published and national data about pediatric BP in Iran, our search was conducted in Pub Med, Medline, ISI, and Scopus, as well as in national databases including Scientific Information database (SID), IranMedex and Irandoc from 1990 to 2014.

Results:

We found 1373 records in the primary search including 840 from international and 533 from national databases. After selection and quality assessment phases, data were extracted from 36 papers and four national data sources. Mean systolic BP (SBP) varied from 90.1 ± 14 mmHg (95% CI 89.25, 90.94) to 120.2 ± 12.3 (118.98, 121.41) mmHg, and for diastolic BP (DBP) from 50.7 ± 11.4 (50.01, 51.38) to 79.2 ± 12.3 (77.95, 80.44) mmHg. The frequency of elevated BP had large variation in sub-national studies with rates as low as 0.4% (0.009, 1.98) for high SBP and as high as 24.1% (20.8, 27.67) for high DBP. At national level, three surveys reported slightly raised rates of elevated BP from 2009 to 2012.

Conclusions:

The findings provide practical information on BP levels in Iranian pediatric population. Although differences exist on the findings of various studies, this review underscores the necessity of tracking BP from childhood, and implementing interventions for primordial prevention of hypertension.

Inventory of Determinants of Obesity-Related Behaviors in Adolescents: Development and Psychometric Characteristics

BACKGROUND

The rising prevalence of childhood obesity is a major health problem worldwide. Hence, there is a growing need for health professionals to become capable of assessing the factors that determine lifestyle in a culturally relevant manner.

OBJECTIVES

This study aimed to develop and assess a questionnaire for measuring determinants of obesity-related behaviors in Tehranian adolescents.

PATIENTS AND METHODS

Based on the results of a qualitative study and an extensive literature review, the 44-item "Inventory of determinants of obesity-related behaviors in adolescents (IDOBA)" with eight subscales was developed: 1) unhealthy nutrition and physical inactivity; 2) stress-related eating; 3) perceived inability; 4) perceived lack of threat; 5) perceived priority of educational achievement; 6) perceived acceptability; 7) motivation loss; and 8) lack of support. Validity of IDOBA was assessed, utilizing face, content, and construct validity methods. To confirm face validity, ten overweight/obese adolescents completed the questionnaire. To calculate content validity ratio (CVR) and content validity index (CVI), a different panel of ten experts commented independently on the necessity, relevance, clarity, and simplicity of each item. To assess construct validity using exploratory factor analysis (EFA), a total of 478 adolescents (57.7% male) aged 13 to 18 years, who were recruited from schools, participated in the study. Confirmatory factor analysis (CFA) was used to test whether the data fit the hypothesized measurement model that was derived from EFA. Test-retest and internal consistency methods were used to assess reliability of the IDOBA scale.

RESULTS

All items were perceived as relevant and comprehendible by adolescents. Content validity was confirmed by the panel of experts. The internal consistency, as measured by Cronbach's alpha coefficients, exceeded the minimum reliability standard of 0.60 for eight subscales. No ceiling effects were observed. Detected floor effects ranged from 0.2% for perceived acceptability subscale score to 18.8% for lack of threat subscale score. The EFA suggested an eight-factor construct and the results of the CFA indicated acceptable fit indices for the proposed model. All subscales demonstrated satisfactory test-retest reliability (intra-class correlation coefficient, 0.42 - 0.91) over one month.

CONCLUSIONS

Results provided initial evidence that the IDOBA is a valid and reliable instrument for measuring determinants of obesity-related behaviors in Iranian adolescents, indicating that the questionnaire can be used in future weight management programs for Tehranian adolescents.

An overview on the successes, challenges and future perspective of a national school-based surveillance program: the CASPIAN study

The Childhood and Adolescence Surveillance and PreventIon of Adult Non-communicable disease (CASPIAN) study is implemented in the Islamic Republic of Iran from 2003. The aim of this national school- based surveillance program was to provide accurate data of regular surveys of this program to be reviewing methodology, protocols, data collection and questionnaires of these surveys. Information was obtained from articles and books were published from CASPIAN studies. The CASPIAN studies were repeated every two years, with blood sampling for biochemical factors every four years. Methods and questionnaires of all surveys were similar at their core level and some optional factors added in different surveys. The results of CASPIAN studies represent the public health of Iranian children and adolescents that are useful for policy makers and based on them, intervention programs can set in national and sub-national level.

School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6 to 18

BACKGROUND

The World Health Organization (WHO) estimates that 1.9 million deaths worldwide are attributable to physical inactivity and at least 2.6 million deaths are a result of being overweight or obese. In addition, WHO estimates that physical inactivity causes 10% to 16% of cases each of breast cancer, colon, and rectal cancers as well as type 2 diabetes, and 22% of coronary heart disease and the burden of these and other chronic diseases has rapidly increased in recent decades.

OBJECTIVES

The purpose of this systematic review was to summarize the evidence of the effectiveness of school-based interventions in promoting physical activity and fitness in children and adolescents.

SEARCH METHODS

The search strategy included searching several databases to October 2011. In addition, reference lists of included articles and background papers were reviewed for potentially relevant studies, as well as references from relevant Cochrane reviews. Primary authors of included studies were contacted as needed for additional information.

SELECTION CRITERIA

To be included, the intervention had to be relevant to public health practice (focused on health promotion activities), not conducted by physicians, implemented, facilitated, or promoted by staff in local public health units, implemented in a school setting and aimed at increasing physical activity, included all school-attending children, and be implemented for a minimum of 12 weeks. In addition, the review was limited to randomized controlled trials and those that reported on outcomes for children and adolescents (aged 6 to 18 years). Primary outcomes included: rates of moderate to vigorous physical activity during the school day, time engaged in moderate to vigorous physical activity during the school day, and time spent watching television. Secondary outcomes related to physical health status measures including: systolic and diastolic blood pressure, blood cholesterol, body mass index (BMI), maximal oxygen uptake (VO2max), and pulse rate.

DATA COLLECTION AND ANALYSIS

Standardized tools were used by two independent reviewers to assess each study for relevance and for data extraction. In addition, each study was assessed for risk of bias as specified in the Cochrane Handbook for Systematic Reviews of Interventions. Where discrepancies existed, discussion occurred until consensus was reached. The results were summarized narratively due to wide variations in the populations, interventions evaluated, and outcomes measured.

MAIN RESULTS

In the original review, 13,841 records were identified and screened, 302 studies were assessed for eligibility, and 26 studies were included in the review. There was some evidence that school-based physical activity interventions had a positive impact on four of the nine outcome measures. Specifically positive effects were observed for duration of physical activity, television viewing, VO2 max, and blood cholesterol. Generally, school-based interventions had little effect on physical activity rates, systolic and diastolic blood pressure, BMI, and pulse rate. At a minimum, a combination of printed educational materials and changes to the school curriculum that promote physical activity resulted in positive effects.In this update, given the addition of three new inclusion criteria (randomized design, all school-attending children invited to participate, minimum 12-week intervention) 12 of the original 26 studies were excluded. In addition, studies published between July 2007 and October 2011 evaluating the effectiveness of school-based physical interventions were identified and if relevant included. In total an additional 2378 titles were screened of which 285 unique studies were deemed potentially relevant. Of those 30 met all relevance criteria and have been included in this update. This update includes 44 studies and represents complete data for 36,593 study participants. Duration of interventions ranged from 12 weeks to six years.Generally, the majority of studies included in this update, despite being randomized controlled trials, are, at a minimum, at moderate risk of bias. The results therefore must be interpreted with caution. Few changes in outcomes were observed in this update with the exception of blood cholesterol and physical activity rates. For example blood cholesterol was no longer positively impacted upon by school-based physical activity interventions. However, there was some evidence to suggest that school-based physical activity interventions led to an improvement in the proportion of children who engaged in moderate to vigorous physical activity during school hours (odds ratio (OR) 2.74, 95% confidence interval (CI), 2.01 to 3.75). Improvements in physical activity rates were not observed in the original review. Children and adolescents exposed to the intervention also spent more time engaged in moderate to vigorous physical activity (with results across studies ranging from five to 45 min more), spent less time watching television (results range from five to 60 min less per day), and had improved VO2max (results across studies ranged from 1.6 to 3.7 mL/kg per min). However, the overall conclusions of this update do not differ significantly from those reported in the original review.

AUTHORS' CONCLUSIONS

The evidence suggests the ongoing implementation of school-based physical activity interventions at this time, given the positive effects on behavior and one physical health status measure. However, given these studies are at a minimum of moderate risk of bias, and the magnitude of effect is generally small, these results should be interpreted cautiously. Additional research on the long-term impact of these interventions is needed.

Associations between physical activity and health parameters in adolescent pupils in Egypt

Physical activity (PA) could be protective against hypertension, atherosclerosis, coronary heart disease and cardiovascular disease. This quantitative study assessed the association between a PA intervention and three anthropometric parameters (weight, body mass index, body fat) and four physiological parameters (cholesterol level, systolic blood pressure, diastolic blood pressure, heart rate) among secondary school pupils (N = 160) in Egypt through the school term. The pupils were randomised to an intervention group (80 pupils) and controls (80 pupils). Measurements were obtained for all pupils twice: at baseline; and then again after three months. The PA intervention programme comprised an ‘afterschool’ one hour of moderate exercise three times a week for three months. Both the controls and the intervention pupils attended the ‘normal’ exercise schedule provided by the school; in addition, the intervention group attended afterschool PA programme from about 2–3 o’clock in the afternoon. At baseline, employing pupil’s BMI, 27.5% and 28.8% of the intervention and control pupils respectively were classified as overweight. After three months, the percentage of overweight decreased to 12.5% in the intervention pupils, while it increased to 37.3% in the controls. At the end of the three months period, there were significant improvements across most anthropometric and physiological parameters of the intervention pupils when compared with the control children. The correlation coefficient of the improvements for the boys and the girls was 0.97, indicating clearly that the intervention was having nearly the same beneficial effect for boys and girls. A moderate PA programme for a modest period of 3 months could be effective in maintaining or enhancing pupil’s anthropometric and physiological parameters in comparison to the controls where there was deterioration in both parameters. Policy makers and secondary schools in Egypt might need to pay more attention to PA programmes conducted on school days, in order to motivate pupils to attend such programmes. There is also an urgent need to look at current PA systems within schools in Egypt in order to assess PA outside school times.