Characterising very early diet exposures: development of a complementary feeding index

Rebecca K GolleyPhD APD

Research Fellow Public Health GroupSansom Institute for Health ResearchUniversity of South Australia, Adelaide

Acknowledgements

Lisa G Smithers2, Murthy N Mittinty2, Laima Brazionis2, Pauline Emmett3, Karen Campbell4, Sarah McNaughton4, Kate Northstone3, John W Lynch2,3

1University of South Australia, 2University of Adelaide, Australia, 3University of Bristol, England, 4Deakin University, Australia

Funding support: RKG is supported by the National Health and Medical Research Council of Australia.

Why the Complementary Feeding Period?

• Nutritionally sensitive period– Breastfeeding duration– Age of introduction of solids– Type, amount and composition of food

• Supply of energy and nutrients

• Establishment of lifelong dietary behaviours – Food habits – Taste and texture preferences

• Implications for later diet, health and development

What’s the Challenge?

• Three studies ‘diet quality’ <12 mo age Smithers et al Nutr Reviews 2011

• Nutrient adequacy, Diet diversity• Child Feeding Index

• Complementary feeding guidelines– Sufficient nutritious food for growth, development

& health (amount, quality, variety, moderation)– Developmentally appropriate (timing, texture)– ‘How’ to feed (responsive feeding, persistence)

Study Aim

• To development an index to characterise quality of the complementary feeding period– adherence to complementary feeding guidelines– developed country context– address (some) methodological challenges

• To examine the face validity of the Complementary Feeding Utility Index (CFUI)– Food and nutrient intake– sociodemographic characteristics– Dietary patterns in childhood

Summary of Diet Index Construction

Selection of index components

Quantification of component scores

Summing of component scores

TOTAL SCORE ‘Diet quality’Adapted Kourlaba et al 2009

Breastfeeding duration months

Fed on demand categorical

Timing introduction complementary foods months

Exposure to iron-rich (i.e. fortified) cereals yes: no

Early meat, fish, egg variety 0,1,2,3

Frequency of fruit and vegetables exposure (2) times/day

Early introduction of tea yes: no

Exposure to sugary drinks & EDNP foods (2) 0-5/6

Early introduction of cow's milk yes: no

Timing of introduction of lumpy foods months

Homemade: ready-prepared meals ratio

Meal routine number of meals/day

CFUI: 14 componentsBreastfeeding (months)0 1 2 3 4 5 6 7 8 9 10 11 120 5 10

Energy dense nutrient poor foods (types)0 1 2 3 4 5 60 5 10

Fed on demand (categorical )N S Y0 5 10

Indicator Score ApproachBreastfeeding duration Mth BF/12 Fed on demand EmpiricalTiming introduction complementary foods TheoreticalExposure to iron-rich (i.e. fortified) cereals EmpiricalEarly meat, fish, egg variety EmpiricalFrequent vegetables exposure TheoreticalFrequent fruit exposure TheoreticalEarly introduction of tea EmpiricalDegree of exposure to sugary drinks Theoretical

Degree of exposure to confectionary, cakes and biscuits, savoury snacks

Theoretical

Early introduction of cow's milk EmpiricalTiming of introduction of lumpy foods EmpiricalRatio home-: ready-prepared meals EmpiricalMeal routine 6mths Empirical

Quantification of component scores: Conversion to Probabilities

Variety of Protein foods

= # children having 1 to 3 types protein foods - # having 1 or 2 or 3 types# children having 1 to 3 types protein foods

= 9747 - # children having 1 type protein foods i.e. 47359747

= 0.51

Quantification of component scores: Theoretical Derived Probabilities

How to derive a total score?• Each component has score of 0 to 1• Sum or mean: various pathways=same score• Inverse Euclidian norm: how each component

score varies from guideline adherence

C 1 C 2 C 3 Traditional Score CFUI Score

P1 0.0 0.1 0.1 0.2/ 3 (mean 0.07) 0.06

P2 1.0 1.0 0.8 2.8/ 3 (mean 0.9) 0.9

P3 1.0 1.0 0.1 2.1/3 (mean 0.7) 0.5

P4 0.7 0.7 0.7 2.1/3 (mean 0.7) 0.7

N=60656 mo

Mean CFUI score = 0.48±0.1

Index component % scoring minimum

% scoring maximum

Breastfeeding duration 21 11 Feeding on demand 18 40 Solids introduction 72 <1 Iron-rich cereals 11 89 Vegetables 3 <1 Fruit 8 <1 Meat, fish, egg variety 11 8 Types sugary drinks <1 26 Sweets, cakes, snacks <1 56 Introduction cow's milk 54 45 Exposure to tea 6 94 Lumpy foods 6 60 Commercial infant foods 4 11 Meal Routine 1 96

Association with energy-adjusted nutrient intake

Nutrient intake at 8 months of age for Children In Focus sub-sample (n=989)

Q1 2 3 4 Q5 P trend

Energy intake, kJ 3488 3394 3378 3384 3375 0.147 Protein, g 27.7 26.9 26.5 26.2 25.9 <0.001 Saturated fat, g 15.2 14.2 13.8 13.5 13.7 <0.001 Total sugar, g 65.5 67.8 68.4 70.1 69.5 <0.001 NSP, g 2.5 2.8 3.1 3.3 3.8 <0.001 Sodium, mg 644 602 594 585 603 0.084 Calcium, mg 741 707 662 614 583 <0.001 Iron, mg 9.7 10.1 10.3 9.9 9.0 0.052 Zinc, mg 3.3 3.4 3.4 3.3 3.2 <0.001 Selenium, ug 11.4 10.6 10.8 11.9 13.6 0.003 Iodine, ug 89.1 84.1 82.2 79.6 79.0 <0.001 Folate, ug 97 104 107 103 106 0.002 Vitamin C, mg 84.9 91.9 88.7 94.4 87.1 0.575

Socio-demographic factors

• Higher Complementary Feeding Utility Index scores were associated with– older maternal age– higher maternal education level – Healthy maternal weight status.

• Higher Complementary Feeding Utility Index scores were not associated with– Number of siblings

Association with Dietary Patterns at 3 y

Adjusted models; dietary pattern scores, child, maternal and family socio-demographics

Complementary Feeding Utility

Index Score

Dietary pattern

scores

β 95% CI P value

Lower Upper

Junk -0.234 -0.260 -0.209 <0.001

Healthy 0.185 0.155 0.215 <0.001

Traditional 0.013 -0.018 0.045 0.408

Snacks 0.017 -0.013 0.047 0.254

N=6065

Conclusions• The Complementary Feeding Utility Index

– reflects adherence to early feeding guidelines– has face validity as a composite measure of early diet quality– scores were associated with food and nutrient intake largely

in the expected direction

• Methodological challenges addressed– components that are unit free– Scoring range based on observed/ theoretical preferences– Contribution of components to total score

• Next steps– Predictive validity: association with child health and

development outcomes

THANK YOU!Questions?