Social inequalities in infant feeding during the first year of life. The Longitudinal Study of Child Development in Québec (LSCDQ 1998-2002).

OBJECTIVE: The aim of this paper is to describe the source and the scope of social inequalities in infant feeding practices. It examines the extent to which different recommendations are followed in different social groups and highlights the main factors influencing the total adherence to three recommendations at the population level. DESIGN, SETTING AND
SUBJECTS: The study follows a representative sample (n=2103) of the children born in 1998 in the province of Québec (Canada). Detailed information on breast-feeding and complementary feeding was collected at 5 and 17 months by face-to-face interviews with the mother. The independent variables were mother's age, mother's education level, poverty level, family type, socio-economic status (SES) and living area. Odds ratios (adjusted for baby's rank in the family, birth weight and premature birth) are presented for breast-feeding, and for formula and cows' milk consumption, at different ages. The adherence to a combined indicator cumulating three recommendations (breast-fed at birth, complementary food at 4 months or later and cows' milk at 9 months or later) is also presented.
RESULTS: The analysis indicates that adherence to the recommendations is low in Québec. Breast-feeding initiation, duration and its exclusivity improved with mother's age and education level and SES. Adherence to the different recommendations was interrelated, indicating an accumulation of bad nutritional circumstances for children in low-SES families. The odds of being fed in accordance with the three studied recommendations, when living in a family with the highest SES, was 2.3 times higher than when living in a family with the lowest SES. When living with a highly educated mother, the odds ratio was 2.7 times higher than when living with a low-educated mother. For mother's age, the odds ratio reached 3.7 for children from mothers aged > or =35 years, in comparison with children from mothers < or =24 years old. When SES or mother's education level was combined with mother's age, the children in the best situation were >8 more times likely than the least privileged children to be fed in accordance with these recommendations. Living area was not related with infant feeding during the first year of life.
CONCLUSIONS: Breast-feeding and nutrition could be related with different health and cognitive outcomes in childhood and later in life. Consequently, social disparities in diet during infancy could play a role in the development of social and health inequalities more broadly observed at the population level. Intervention to improve adherence to breast-feeding and nutrition recommendations in infancy should be prioritised and evaluated for its impact on the reduction on infant diet inequalities over time.