Proportionate universalism intervention is effective for tackling nutritional social gradient in adolescents: the PRALIMAP-INÈS mixed randomised trial

Abstract

ObjectiveThis study aimed to investigate the effectiveness of proportionate universalism intervention to reduce the slope of the nutritional social gradient in adolescents. Study designA mixed (experimental and quasi-experimental) multicentre trial. MethodsData from 985 adolescents of the PRALIMAP-INÈS trial (North-eastern France, 2012–2015) were analysed. For this, adolescents were split into five social classes according to the Family Affluence Scale: Highly Less Advantaged (H.L.Ad; n = 33), Less Advantaged (L.Ad; n = 155), Intermediate (Int; n = 404), Advantaged (Ad; n = 324) and Highly Advantaged (H.Ad; n = 69). The overweight care management was a standard care for all and a strengthened one adapted to the social class of adolescents. The main outcome was the 1-year change of the body mass index z-score (BMIz) slope. Other nutritional outcomes were BMI, ΔBMIp95 (BMI minus 95th percentile of the WHO reference), %BMIp95 (percent of 95th percentile of the WHO reference), leisure-time sport, consumption of fruits and vegetables and consumption of sugary foods and drinks. ResultsThe inclusion data confirmed a weight social gradient expressed by a significant BMIz linear regression coefficient (β = −0.09 [−0.14 to −0.04], P < 0.0001). The higher the social class, the lower the BMIz. The 1-year BMIz linear regression coefficient was −0.07 [−0.12 to −0.02], corresponding to a significant weight social gradient reduction of 23.3% (β = 0.021 [0.001 to 0.041]; P = 0.04). Consistent results were found for other nutritional outcomes. ConclusionsPRALIMAP-INÈS shows that proportionate universalism intervention is effective to reduce the adolescents’ nutritional social gradient and suggests that equitable health programmes and policies are a realistic goal.