Infant nutrition and growth: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982-2015

BACKGROUND

Levels of child undernutrition have declined in many middle-income countries, whereas overweight and obesity have increased. We describe time trends in nutritional indicators at age 1 year in the 1982, 1993, 2004 and 2015 Pelotas (Brazil) Birth Cohorts.

METHODS

Each study included all children born in the urban area of the city, with over 4 200 births in each cohort. Children were measured at approximately 12 months of age. Anthropometric indicators were calculated according to World Health Organization Growth Standards. Stunting and wasting were defined as <-2 Z scores for length for age and weight for length, and overweight as >2 Z scores for weight for length. Prevalence was stratified by sex, maternal skin colour and family income.

RESULTS

The prevalence of stunting declined by 53% (from 8.3% to 3.9%) from 1982 to 2015. Wasting prevalence remained stable at low levels (1.8% in 1982 and 1.7% in 2015), whereas overweight increased by 88% (6.5% to 12.2%). Undernutrition was more common among boys, those born to mothers with brown or black skin colour and in the poorest quintile of families. Socioeconomic inequalities in undernutrition decreased markedly over time. Overweight was markedly more common among the rich in 1982, but fast increase among the poor eliminated socioeconomic differences by 2015, when all groups showed similar prevalence.

CONCLUSIONS

Our results confirm the rapid nutrition transition in Brazil, with marked reduction in levels and inequalities in undernutrition in parallel with a rapid increase in overweight, which became the main nutritional problem for children.

Malnutrition and its associated factors: a cross-sectional study with children under 2 years in a suburban area in Angola

BACKGROUND

The prevalence of child malnutrition in Angola is still very high, and little is known about its associated factors. The aim of this study was to identify these factors in children under 2 years in a suburban area of the country's capital city.

METHODS

We used data from a cross-sectional population-based study conducted in 2010. The outcomes studied were stunting and underweight. Multivariable analysis was conducted; prevalence ratios were estimated by Poisson regression with robust variance using a hierarchical model.

RESULTS

Of the children studied (N = 749), 232 [32.0% (95% CI: 28.7-35.5%)] were stunted and 109 [15.1% (95% CI: 12.6-17.9%)] were underweight. In multivariable analysis, occurrence of diarrhea (PR 1.39 [95% CI: 1.07-1.87]) and the death of other children in the household (PR 1.52 [95% CI: 1.01-2,29]) were associated with stunting and underweight, respectively. In the model composed only of distal and intermediate factors, the primary caregiver not being the mother increased the prevalence of stunting by 42% (PR 1.42 [95% CI: 1.10-1.84], and a mother's working outside the house while not being self-employed was associated with its reduced prevalence (PR 0.55 [95% CI: 0.34-0.89]). In the intermediate model, each additional month of delay in the onset of prenatal care increased the relative prevalence of underweight by 20% (PR 1.20 [95% CI: 1.03-1.40]).

CONCLUSIONS

Despite the high prevalence rates of stunting and underweight, relatively few risk factors were identified for these conditions, suggesting that collective exposures are likely to play a major role in causing malnutrition in Angola. The individual factors identified can be useful for the development of strategies to deal with this public health problem.

Iron and vitamin D status in breastfed infants and their mothers

Purpose

We assessed the relationships between iron and vitamin D statuses in breastfed infants and their mothers and evaluated the determinants of iron and vitamin D deficiencies in breastfed infants.

Methods

Seventy breastfed infants aged 4-24 months and their mothers participated in this study from February 2012 to May 2013. Complete blood counts, total iron binding capacity, and levels of C-reactive protein, iron, ferritin, calcium, phosphate, alkaline phosphatase, and 25-hydroxyvitamin D (25(OH)D) in infants and their mothers were measured.

Results

A history of maternal prepregnancy anemia was associated with lower ferritin and 25(OH)D levels in both infants and their mothers. The 25(OH)D level of infants correlated with maternal 25(OH) D levels. The independent risk factors for iron deficiency in breastfed infants were the duration of breastfeeding (odds ratio [OR], 6.54; 95% confidence interval [CI], 1.09-39.2; P=0.04) and infant body weight (OR, 2.65; 95% CI, 1.07-6.56; P=0.04). The determinants for vitamin D deficiency were the infant's age (OR, 0.15; 95% CI, 0.02-0.97; P=0.046) and maternal 25(OH)D level (OR, 0.74; 95% CI, 0.59-0.92; P=0.01).

Conclusion

A maternal history of prepregnancy anemia requiring iron therapy was associated with lower current ferritin and 25(OH)D levels in both infants and their mothers. Therefore, physicians should monitor not only iron but also vitamin D levels in infants who are breastfed by mothers who had prepregnancy anemia.