Universal School-Based Intervention Does Not Reduce Socioeconomic Inequalities in Weight Status among Adolescents

Abstract

Background: Differences in weight status by socioeconomic position occur during adolescence and is known as weight social gradient (WSG). The PRALIMAP (Promotion de l'ALIMentation et de l'Activité Physique) trial highlighted that a universal intervention was effective in reducing overweight and obesity prevalence among adolescents. However, its ability to reduce the WSG is unclear. This study aimed to evaluate the impact of the PRALIMAP intervention on the WSG among adolescents. Methods: Data were obtained from 3504 adolescents who participated in the school-based PRALIMAP trial between 2006 and 2009. The PRALIMAP study consisted of three interventional strategies: educational, environmental, screening and care. Weight status was assessed by body mass index (BMI) z-score and overweight and obesity prevalence. The ''indice de position sociale des élèves'' was used to measure adolescents' socioeconomic status. Linear regression and hierarchical models were used to assess the WSG and its evolution, respectively. Results: Among all adolescents (14-18 years old), significant WSG was identified at baseline: BMI z-score (b =-0.06; p < 0.0001), overweight and obesity prevalence (b =-2.86; p < 0.0001). Overall, the intervention conferred no significant reduction in the WSG: BMI z-score (b =-0.01 [-0.02 to 0.01], p = 0.48), overweight and obesity prevalence (b =-0.01 [-0.07 to 0.05], p = 0.73). Similar results were observed for adolescents whatever the interventional strategy they benefited from in the PRALIMAP trial. Conclusions: This study provided no evidence that the PRALIMAP universal intervention was effective in reducing the socioeconomic inequalities in weight status among adolescents. Different interventions that account for social differences should be considered to tackle these inequalities.

Effectiveness of interventions to reduce social inequalities of weight status in adolescents: A systematic review and meta‐analysis

“…Among the three universal interventions, two reported BMI 44,66 and BMI z score 37,44 and did not reduce the social gradient in these outcomes. No intervention reported percent body fat.…”

“…A total of six (18%) RCTs had more than one intervention group. They evaluated various components such as parental involvement, 45 different strategies, 37,46 diet or nutrition advice, 54 or the adaptation of interventions according to SES 34 …”

“…Elèves (n = 1). 37 There was no objective measurement of SES in 11 papers. 47,48,50,55,56,59,60,62,64,65,68…”

Role of dietary intake and physical activity in reducing weight social inequalities among adolescents: an application of G-formula to PRALIMAP-INÈS trial

“…The results of this study confirm low levels of achieving lifestyle guidelines in adolescents regardless of SES with social inequalities in weight status (likelihood of a 1-year reduction in BMIz under each scenario). Differences by SES in obesity-related behaviours with a high prevalence of unhealthy lifestyle behaviours in adolescents with low SES result in social gradient of lifestyle behaviours (8) and weight status (29) .…”

Longitudinal patterns of lifestyle behaviours in adolescence: a latent transition analysis

“…IPSE is derived from both parents' occupation, and each student is assigned an IPSE ranging from 40 (low SES) to 179 (high SES) (28) . Then, the IPSE was re-scaled from 1 to 10 and classified in five SES categories (1-2: highly less advantaged, 3-4: less advantaged, 5-6: intermediate, 7-8: advantaged and 9-10: highly advantaged) (29) .…”