World Health Organization growth standards: How do Canadian children measure up?

Celia Rodd; Allison Feely; Allan B Becker; Theo J Moraes; Padmaja Subbarao; Piushkumar J Mandhane; Stuart E Turvey; Diana L Lefebvre; Malcolm R Sears; Meghan B Azad; Atul Sharma

doi:10.1093/pch/pxaa053

World Health Organization growth standards: How do Canadian children measure up?

Paediatr Child Health. 2020 Jul 18;26(5):e208-e214. doi: 10.1093/pch/pxaa053. eCollection 2021 Aug.

Authors

Celia Rodd¹, Allison Feely², Allan B Becker^{1

3}, Theo J Moraes⁴, Padmaja Subbarao⁴, Piushkumar J Mandhane⁵, Stuart E Turvey⁶, Diana L Lefebvre⁷, Malcolm R Sears⁷, Meghan B Azad^{1

3}, Atul Sharma¹

Affiliations

¹ Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, Manitoba.
² George and Fay Yee Centre for Health Care Innovation, University of Manitoba, Winnipeg, Manitoba.
³ Manitoba Developmental Origins of Chronic Diseases in Children Network (DEVOTION), Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba.
⁴ Departments of Pediatrics, University of Toronto, Toronto, Ontario.
⁵ Department Pediatrics, University of Alberta, Edmonton, Alberta.
⁶ Department of Pediatrics, University of British Columbia, Vancouver, British Columbia.
⁷ Department of Medicine, McMaster University, Hamilton, Ontario.

Abstract

Background: World Health Organization (WHO) growth standards for children aged 0 to 5 years describe growth under optimal conditions and were adopted for use in Canada in 2012. We are seeking to validate these charts in a well-characterized, longitudinal cohort of healthy, Canadian youngsters, assess tracking over time, and evaluate the prognostic implications of early growth.

Methods: Data from 2,795 mother-infant dyads from the CHILD birth cohort were classified by feeding modality at 6 months as exclusively breastfed, partially breastfed, or formula-fed. WHO z-scores (z) were calculated at birth, 3 months, 1 year, and 3 years. Receiver operator characteristics (ROC) assessed the predictive performance of early weight (WT), weight-for-length (WfL), or body mass index (BMI) z-scores for overweight/obesity at 3 years.

Results: Compared to WHO standards, Canadian children at birth had lower median WfLz (-0.73) and BMIz (-0.29), with more positive scores by 3 years (WfLz=BMIz=0.58). At both 1 and 3 years, formula feeding was associated with higher scores than breastfeeding, even after regression adjustment for covariates. Head circumference z-score was typically positive at all times and regardless of feeding modality. At 1 year, ROC area under the curve was 0.79 for WTz, WfLz, and BMIz, and BMIz>0.88 identified children with increased risk of overweight/obesity (BMIz >2) at age 3 years (20.3% versus 3.0%, P<0.001).

Conclusions: Compared to WHO growth charts, Canadian children at 3 years show an upward shift in BMIz and WfLz, particularly when formula-fed. Infant growth parameters may identify infants with increased risk of overweight/obesity at age 3 years; early recognition may allow targeting infants at higher risk.

Keywords: Adiposity; Bottle feeding; Breastfeeding; Growth.