Describing the longitudinal breakfast quality index trajectories in early childhood: results from Melbourne InFANT program

BACKGROUND: Breakfast quality in early childhood remains understudied. This study describes the changes in breakfast quality index (BQI) (i.e. trajectory) in early childhood and assesses its associations with obesity outcomes. METHODS: Data from children who participated in the Melbourne InFANT Program were used (n = 328). The Melbourne InFANT Program was a 15-month early obesity prevention intervention conducted from 2008 to 2013. Dietary intakes at ages 1.5, 3.5 and 5.0 years were assessed using three parent-proxy reported 24 h recalls. A revised nine-item BQI tool developed based on Australian dietary recommendations for young children was used to calculate BQI scores. Group-based trajectory modelling identified BQI trajectory groups. Multivariable linear and logistic regression examined the associations between identified BQI trajectory groups and obesity outcomes at age 5 years. RESULTS: Mean BQI at ages 1.5, 3.5 and 5.0 years was 4.8, 4.8, 2.7 points, respectively. Two BQI trajectory groups were identified, and both showed a decline in BQI. The mean BQI of most children (74%) decreased from 5.0 to 4.0 points from ages 1.5 to 5.0 years (referred as "High BQI " group). The remaining children (26%) had a mean BQI of 4.8 and 1.2 points at age 1.5 and 5.0 years, respectively (referred as "Low BQI " group). The "Low BQI " group appeared to show higher risk of overweight (OR:1.30, 95% CI: 0.60, 2.81, P = 0.66) at age 5 years than the "High BQI " group. No difference in body mass index (BMI) z-score was found between the two groups. CONCLUSIONS: Two BQI trajectory groups were identified. Both groups showed a decline in breakfast quality from ages 1.5 to 5.0 years. Our study highlights the need for early health promotion interventions and strategies to improve and maintain breakfast quality across early childhood.