Longitudinal assessment of childhood dietary patterns: Associations with body mass index z-Score among children in the Samoan Ola Tuputupua'e (Growing Up) cohort

Background: Intervention strategies to prevent childhood obesity in the Pacific Islands encourage eating a variety of local and traditional foods, but context-specific data to support this approach are limited. The objective was to assess the association between 2-year adherence to modern and neotraditional dietary patterns and body mass index z-scores (BMIz) among Samoan children. Methods: A convenience sample of 214 Samoan biological mother-child dyads who participated in the Ola Tuputupua'e “Growing Up” cohort study in 2015 and 2017 was included. At each time point, modern and neotraditional dietary patterns were identified using food frequency data and factor analysis. Children were assigned to categories based on diet pattern adherence: consistently high, high to low, low to high, and consistently low. Associations between 2-year adherence to dietary patterns, BMIz (in 2017 and 2015–2017), and weight and height z-scores were examined using linear models adjusted for potential confounders. Results: Consistently high adherence to the modern pattern was associated with a 0.36 standard deviation (SD)-adjusted change in BMIz between 2015 and 2017 (95% confidence interval [CI]: 0.04–0.69, p = 0.03). While the estimates for the individual components of BMI were imprecise, on average, children with consistently high adherence to the modern pattern had a 0.13 SD greater change in weight z-score (95% CI: −0.10 to 0.37) and 0.15 SD lower change in height z-score (95% CI: −0.43 to 0.13). The change in BMIz between 2015 and 2017 did not significantly differ by adherence to the neotraditional pattern. Conclusion: A neotraditional dietary pattern, comprising local produce, should be encouraged as a possible childhood obesity prevention strategy in Samoa.