Effect of Volunteering on Risk Factors for Cardiovascular Disease in Adolescents: A Randomized Controlled Trial

Abstract

IMPORTANCE: The idea that individuals who help others incur health benefits themselves suggests a novel approach to improving health while simultaneously promoting greater civic orientation in our society. The present study is the first experimental trial, to our knowledge, of whether regular volunteering can reduce cardiovascular risk factors in adolescents. OBJECTIVE: To test a novel intervention that assigned adolescents to volunteer with elementary school-aged children as a means of improving adolescents' cardiovascular risk profiles. DESIGN: Randomized controlled trial, with measurements taken at baseline and 4 months later (postintervention). SETTING: Urban public high school in western Canada. PARTICIPANTS: One hundred six 10th-grade high school students who were fluent in English and free of chronic illnesses. INTERVENTION: Weekly volunteering with elementary school-aged children for 2 months vs wait-list control group. MAIN OUTCOME MEASURES: Cardiovascular risk markers of C-reactive protein level, interleukin 6 level, total cholesterol level, and body mass index. RESULTS: No statistically significant group differences were found at baseline. Postintervention, adolescents in the intervention group showed significantly lower interleukin 6 levels (log10 mean difference, 0.13; 95% CI, 0.004 to 0.251), cholesterol levels (log10 mean difference, 0.03; 95% CI, 0.003 to 0.059), and body mass index (mean difference, 0.39; 95% CI, 0.07 to 0.71) compared with adolescents in the control group. Effects for C-reactive protein level were marginal (log10 mean difference, 0.13; 95% CI, -0.011 to 0.275). Preliminary analyses within the intervention group suggest that those who increased the most in empathy and altruistic behaviors, and who decreased the most in negative mood, also showed the greatest decreases in cardiovascular risk over time. CONCLUSIONS AND RELEVANCE: Adolescents who volunteer to help others also benefit themselves, suggesting a novel way to improve health. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01698034.