School-based interventions offer opportunity to promote cardiovascular health in adolescents

Cardiovascular diseases (CVD), particularly stroke and ischemic heart disease, remain the most common causes of premature death globally. The high incidence of CVD has been attributed to unhealthy lifestyles and obesity.

Several other factors including smoking, adverse lipid profile, and elevated blood pressure also increase the risk of CVD events. In fact, the presence of these risk factors between early life and adulthood is considered a prominent predictor of CV events later in life.

Thus, there remains an urgent need to implement early actions, such as inhibiting the use of tobacco and other illegal drugs, consuming a balanced diet, and regular physical activity to reduce the risk of adverse CV health (CVH). 

Study: School-Based Cardiovascular Health Promotion in Adolescents: A Cluster Randomized Clinical Trial. Image Credit: Jacob Lund / Shutterstock.com

Background

Adolescence is a vital phase of life that determines one’s lifestyle choices. A recent study revealed that being overweight during puberty increases the risk of type 2 diabetes in middle and late adulthood. These studies emphasize the importance of healthy lifestyle choices in the early phase of life or adolescence. 

Although schools are ideal for this type of intervention, few school-based health promotion trials linked to adolescents have been conducted. The Salud Integral Program (SI! Program) is a multidimensional educational intervention that involved families, teachers, and the school environment to highlight the importance of healthy lifestyle behaviors from early childhood through adolescence.

Previously, SI! Program studies were conducted among pre-schoolers, which revealed the importance of favorable timing to achieve persistent positive effects. This timing depends on numerous factors including intervention intensity and duration, as well as the age of the targeted population.

About the study

A recent JAMA Cardiology discusses the outcomes of the SI! Program for Secondary Schools trial in adolescence in Spain. The primary objective of this randomized clinical trial (RCT) was to evaluate the effect of two multicomponent educational health promotion strategies of differing duration and intensity on adolescents’ CVH.

The study was designed as a cluster randomized controlled intervention to determine whether a comprehensive lifestyle program on CVH affected adolescents between 12 and 16 years of age in Spain. The SI! program for secondary schools trial was initiated on September 7, 2017, and completed on July 31, 2021.

Public schools located in the metropolitan areas of Barcelona and Madrid were selected for the study. Schools that participated in the study were randomly assigned in a 1:1:1 ratio to receive a comprehensive educational program through a long-term (four-year) intervention (LTI), a short-term (two-year) intervention (STI), or standard curriculum (control).

Twenty-four secondary schools participated in this study, which comprised a total of 1,326 adolescents. The SI! program adopts a multi-component approach, which focuses on emotion management including self-esteem and assertiveness, health effects of diet and physical activity, and protective behavioral strategies against drug abuse and use of tobacco.

Study findings

Based on primary outcome assessments, 99.8% of adolescents completed the baseline, 91.6% completed the two-year follow-up, and 82.7% completed the four-year follow-up. An overall neutral effect was observed after analyzing the primary results of the trial, which tested educational health promotion strategies on adolescents’ CVH. 

The curriculums of both interventions were similar, in which STI condensed all content in two years and LTI taught the same content in four years. The teachers stated that the study content was very difficult to implement in just two years. Since teachers must also focus on other academic and administrative tasks, a more intense intervention could impact the quality of the interventions.

The current study was affected by government policies, such as national lockdowns, school closures, and self-quarantine periods that were implemented during the coronavirus disease 2019 (COVID-19) pandemic. For example, adolescents only attended schools every other week in the last year of the study.

Some of the interventions related to physical activities were also canceled during this period. The switch to digital platforms was also a significant hurdle for teachers, students, and their families.

Conclusions

The SI! Program for Secondary Schools trial was the largest trial to assess a holistic school-based intervention for overall CVH promotion in adolescents. Overall, the trial results indicate a neutral effect on adolescents’ CVH related to both types of school-based interventions. Nevertheless, LTI exhibited a marginal beneficial effect at the two-year follow-up. 

It is important to emphasize the importance of CVH to adolescents, as their lifestyle behavior has a significant influence on the incidence of CVD later in life. Thus, an age-tailored educational program must be designed to achieve sustained behavioral effects.