Unhealthy habits in adolescents are increasing at an alarming rate. The school offers a promising environment in which to implement effective preventive strategies to improve adolescents' lifestyle behaviors. The SI! Program is a multilevel multicomponent school-based health-promotion intervention aimed at all stages of compulsory education in Spain. We present the study design of the SI! Program for Secondary Schools, targeting adolescents aged 12 to 16 years. The main goal of this study is to evaluate the impact of the SI! Program educational intervention on adolescent lifestyle behaviors and health parameters. The study was designed as a cluster-randomized controlled intervention trial and enrolled 1326 adolescents from 24 public secondary schools in Spain, together with their parents/caregivers. Schools and their students were randomly assigned to the intervention group (the SI! curriculum-based educational program over 2 or 4 academic years) or to the control group (usual curriculum). The primary endpoint will be the change from baseline at 2-year and 4-year follow-up in the composite Ideal Cardiovascular Health (ICH) score, consisting of four health behaviors (body mass index, dietary habits, physical activity, and smoking) and three health factors (blood pressure, total cholesterol, and glucose). Secondary endpoints will include 2-year and 4-year changes from baseline in ICH score subcomponents, the Fuster-BEWAT health scale, adiposity markers (waist circumference and body composition), polyphenol and carotenoid intake, and emotion management. The overarching goal of the SI! Program is to instill healthy behaviors in children and adolescents that can be sustained into adulthood. The SI! Program for Secondary School is a comprehensive health-promotion intervention targeting 12-16-year-old adolescents and their immediate environment. The present study addresses the optimal timing and impact of the educational intervention on health in adolescence.

Implementing a health promotion program for children is a complex endeavor. In this review, we outline the key lessons learned over 10 years of experience in implementing the SI! Program (Salud Integral-Comprehensive Health) for cardiovascular health promotion in preschool settings in 3 countries: Colombia (Bogotá), Spain (Madrid), and the United States (Harlem, New York). By matching rigorous efficacy studies with implementation science, we can help bridge the divide between science and educational practice. Achieving sustained lifestyle changes in preschool children through health promotion programs is likely to require the integration of several factors: 1) multidisciplinary teams; 2) multidimensional educational programs; 3) multilevel interventions; 4) local program coordination and community engagement; and 5) scientific evaluation through randomized controlled trials. Implementation of effective health promotion interventions early in life may induce long-lasting healthy behaviors that could help to curb the cardiovascular disease epidemic.

Importance: School-based interventions offer an opportunity for health promotion in adolescence.Objective: To assess the effect of 2 multicomponent educational health promotion strategies of differing duration and intensity on adolescents’ cardiovascular health (CVH).Design, Setting, and Participants: The SI! Program for Secondary Schools is a 4-year cluster randomized clinical intervention trial conducted in 24 secondary schools from Barcelona and Madrid, Spain, from September 7, 2017, to July 31, 2021. Eligible participants were adolescents enrolled in the first grade of secondary school.Interventions: Schools and their participants were randomized to receive a health promotion intervention (SI! Program) over 4 school years (long-term intervention [LTI], 8 schools, 412 adolescents) or 2 school years (short-term intervention [STI], 8 schools, 504 adolescents) or to receive the standard curriculum (control, 8 schools, 441 adolescents).Main outcome and Measures: The primary end point was the between-group difference at 2 and 4 years in the change from baseline of the overall CVH score, as defined by the American Heart Association (range, 0-14 points, with a higher score indicating a healthier CVH profile). Intervention effects were tested with multilevel mixed-effects models. A complete-case intention-to-treat analysis was performed as the primary analysis.Results: Of the randomized students, the study enrolled 1326 adolescents (684 [51.6%] boys, mean [SD] age, 12.5 [0.4] years at recruitment) with a study completion rate of 86.0%. Baseline overall CVH scores were 10.3 points in the LTI group, 10.6 points in the STI group, and 10.5 points in the control group. After 2 years, at halfway through the LTI and at the end of the STI, the difference in the CVH score change was 0.44 points (95% CI, 0.01-0.87; P = .04) between the LTI group and the control group and 0.18 points (95% CI, −0.25 to 0.61; P = .39) between the STI group and the control group. At 4 years, differences for the LTI and STI groups vs control were 0.12 points (LTI: 95% CI, −0.19 to 0.43; P = .42) and 0.13 points (STI: 95% CI, −0.17 to 0.44; P = .38). No adverse events were reported.Conclusions and Relevance: Overall, the tested school-based health promotion strategies in this randomized clinical trial had a neutral effect on the CVH of the adolescents. Although there was evidence of a marginal beneficial effect at a point halfway through implementation in the LTI group, such a benefit was not noted at 4 years. Further research is warranted into the efficacy of school-based health promotion programs.Trial Registration: ClinicalTrials.gov Identifier: NCT03504059

Unhealthy habits in children are increasing at an alarming rate. The school provides a promising setting for effective preventive strategies to improve children's lifestyle behaviors. The SI! Program is a multilevel multicomponent school-based educational intervention aimed at all stages of compulsory education in Spain. Here, we present the design of the SI! Program for Elementary School cluster-randomized controlled trial, targeting children aged 6 to 11 years. This trial aims to study the impact of different timings and intensities of exposure to SI! Program activities on elementary school children and their immediate environment (parents/caregivers, teachers, and school). The trial includes 1770 children from 48 public elementary schools in Madrid (Spain), together with their parents and teachers. Schools and their children were randomly assigned to the intervention group (the SI! curriculum-based educational program over 3 or 6 academic years) or to the control group (standard curriculum). The primary outcomes are the change from baseline at 3-year and 6-year follow-up in children's scores for knowledge, attitudes, and habits (KAH) and health factors (blood pressure, height, weight, waist circumference, and skinfold thickness). Secondary outcomes include 3-year and 6-year changes from baseline in lifestyle questionnaire scores for parents/caregivers and teachers, and in the school environment questionnaire. The overarching goal of the SI! Program is to provide an effective and sustainable health promotion program for the adoption of healthy behaviors in children. The present trial will address the impact and the optimal timing and duration of this educational intervention in the elementary school setting.

Previous studies on the association between dietary habits and cardiovascular risk factors (CVRF) in adolescents have generated conflicting results. The aim of this study was to describe dietary patterns (DP) in a large sample of Spanish adolescents and to assess their cross-sectional relationship with CVRF. In total, 1324 adolescents aged 12.5 ± 0.4 years (51.6% boys) from 24 secondary schools completed a self-reported food frequency questionnaire. DPs were derived by cluster analysis and principal component analysis (PCA). Anthropometric measurements, blood pressure, lipid profile, and glucose levels were assessed. Linear mixed models were applied to estimate the association between DPs and CVRF. Three DP-related clusters were obtained: Processed (29.2%); Traditional (39.1%); and Healthy (31.7%). Analogous patterns were obtained in the PCA. No overall differences in CVRF were observed between clusters except for z-BMI and z-FMI values, total cholesterol, and non-HDL cholesterol, with the Processed cluster showing the lowest mean values. However, differences were small. In conclusion, the overall association between DPs, as assessed by two different methods, and most analyzed CVRF was weak and not clinically relevant in a large sample of adolescents. Prospective analysis may help to disentangle the direction of these associations.

The results of most school-based health promotion initiatives are inconclusive. This trial assessed the effect of time-varying exposures to a multicomponent school-based health promotion intervention (SI! Program) on adiposity markers. A total of 48 schools in Madrid (Spain) were cluster randomized to receive the SI! Program through elementary education grades 1 to 6 (E1-6, 12 schools, 459 children), 1 to 3 (E1-3, 12 schools, 513 children), or 4 to 6 (E4-6, 12 schools, 419 children) or to receive the standard curriculum (control, 12 schools, 379 children). The primary endpoint was the between-group difference at 3- and 6-year follow-up in the change from baseline in adiposity markers and the overall knowledge-attitudes-habits (KAH) score. At 3-year follow-up, children who had the intervention showed significantly lower increases than the control group in z-scores for body mass index (BMI), waist-to-height ratio (WHtR), and waist circumference (WC) (zBMI: -0.09; 95% CI: -0.16 to -0.03; P = 0.003; zWC and zWHtR: -0.19; 95% CI: -0.28 to -0.10; P < 0.001). At 6-year follow-up, the beneficial trend in zWC and zWHtR was maintained in the E1-6 and E1-3 groups: difference zWC control vs E1-6 (-0.19; 95% CI: -0.36 to -0.03; P = 0.020), control vs E1-3 (-0.22; 95% CI: -0.38 to -0.06; P = 0.009); difference zWHtR control vs E1-6 (-0.24; 95% CI: -0.41 to -0.06; P = 0.009), and control vs E1-3 (-0.29; 95% CI: -0.47 to -0.11; P = 0.001). No significant between-group differences were found in the change of overall KAH score. Early elementary school interventions may be more effective than later interventions on abdominal adiposity. Further research should assess the sustainability effects of school-based health promotion programs.