Two-year controlled effectiveness trial of a school-based intervention to prevent obesity in Chilean children

Abstract

Objective: Obesity prevalence among Chilean children is 19?4 %. The present study aimed to assess the effectiveness of a school-based obesity prevention programme. Design: Non-randomized controlled study. The intervention included activities in nutrition and physical activity, fully applied the first year and partially in the second one. Primary outcomes were BMI Z-score (BMIZ) and obesity prevalence; secondary outcomes were waist circumference and triceps skinfold thickness. Time effects were assessed by changes in BMI-related variables by gender and period (ANOVA and Tukey test), while intervention effects were determined by comparing changes in (i) obesity prevalence by gender and period (PROC GENMOD) and (ii) BMIZ according gender, age and period (PROC MIXED). Setting: Primary schools in the Chilean cities of Casablanca (intervention group) and Quillota (control group). Subjects: One thousand seven hundred and fifty-nine children from three schools (intervention group) and 671 from one school (control group). Results: Over the two years, obesity prevalence and BMIZ declined significantly in the intervention group; from 17?0 % to 12?3 % and 14?1 % to 10?3 % in boys and girls, respectively, and from 0?62 to 0?53 and 0?64 to 0?58, respectively. In the control group, obesity remained stable at about 21 % and 15 %, while BMIZ increased significantly in the second year. BMIZ declined in both genders and all age categories in the intervention group during the first year (significant only in younger boys). No changes occurred during the summer, while during the second year, BMIZ increased in boys and girls from both groups (significant only in the younger control boys). Obesity declined significantly only in boys during the first year. Conclusion: Effectiveness was greater in the first school year and more evident in younger boys. KeywordsPrevention School-based Childhood obesity ChileIn Chile, the prevalence of obesity has risen sharply since the early 1980s (1) and especially in young children, whose obesity rates have increased from 7?0 % in 1987 to 18?5 % in 2005 (2) . This can be attributed to multiple factors linked to the nutrition transition which affect both energy intake and physical activity (3,4) . During the 1980s and 1990s, income more than doubled and poverty dropped by 50 %. Mean energy intake increased, especially among the urban poor. On the energy output side, sedentarism linked to urbanization increased significantly; presently, 87 % of the population live in urban areas and about 90 % are classified as sedentary. The Ministry of Health acknowledged in 1997 the need to address obesity prevention by establishing a national health promotion programme (Vida Chile) with specific goals at each stage of the life course. For children, the goals are to reduce obesity at school entry (6 years of age), using WHO criteria (5) , from 16 % observed in the 2000 baseline to 12 % by the year 2010; and to reduce sedentary behaviour in those 15 years of age and older from 91 % to 84 % (6) .To achieve thes...

Calidad de la alimentación y estado nutricional en estudiantes universitarios de 11 regiones de Chile

“…Aun cuando se han desarrollado diversas estrategias para mejorar las conductas alimentarias y estilos de vida de la población chilena, los resultados obtenidos hasta la fecha han sido limitados [17][18][19] y la prevalencia de obesidad ha continuado en aumento en niños, escolares y adultos.…”

Obesity Control in Latin American and U.S. Latinos

“…For Latino children, school-based interventions provided favorable evidence for targeting obesity prevention efforts. [16][17][18][19][20][21][22][23] For Latino adults, individually based, tailored interventions provided the most promise for the treatment of those who were already overweight or obese. [27][28][29][30][31][32][33][34][35][36][37][38] Intervention in the healthcare context, for both children and adults, also showed great potential to prevent and treat obesity within the Latino population.…”

“…This study intervened with participants at least three times per week and included a parent component consisting of newsletters and homework assignments sent to the home to encourage interactive activity between child and parent. schools, 22,23 and the third study intervention took place in a recreation center. 21 Study duration ranged from 3 to 21 months, and frequency of intervention sessions ranged from once to twice per week.…”

“…21 Study duration ranged from 3 to 21 months, and frequency of intervention sessions ranged from once to twice per week. Two studies had a non-RCT design 22,23 ; the third study was an RCT. 21 Each intervention had one to three limitations in execution.…”

“…[21][22][23] Two of the studies performed interventions at The study with the largest effect size was a non-RCT delivered by teachers and trained nutritionists. 23 Beyond regular physical education class time, students were exposed to 90-minute additional weekly physical education classes for children and active recess during 4 months. Among girls in this study, at post-intervention, the mean BMI for the intervention group was 20.1 (SD = 3.5); the control group had a mean BMI of 20.8 (SD = 3.8).…”