Análise da associação entre as políticas e programas pró-AM e três principais indicadores de AM em países de alta, média e baixa renda

Abstract

Introduction: The World Breastfeeding Trends Initiative (WBTi) was developed as a standardized tool to assist countries in identifying strengths and limitations in breastfeeding promotion policies and programs. The use of the WBTi across different countries, focusing on the impact of breastfeeding policies and programs on indicators over time, reinforces the importance of relating these policies to breastfeeding outcomes, since evidence regarding this association remains limited. Therefore, the objectives of this thesis were: to verify the association between gross domestic product based on purchasing power parity (GDP PPP) and WBTi scores; to assess the association between WBTi scores and the indicators exclusive breastfeeding (EBF), breastfeeding within the first hour of life (BF1h), and continued breastfeeding (continued BF) in high-, middle-, and low-income countries; and to investigate the association between WBTi scores and the outcomes EBF and mixed breastfeeding (mixed BF) during the 2000s and 2020s in low- and middle-income countries.

Methods: All data regarding breastfeeding policies and programs were obtained from the WBTi tool, whereas GDP PPP and countries’ economic classifications were obtained from the World Bank. The first and second objectives were operationalized through ecological studies. Initially, WBTi scores and GDP PPP data from 98 countries were obtained. Means and standard deviations (SD) were estimated for total scores and for each WBTi indicator. ANOVA and Tukey’s tests were used to compare mean WBTi scores according to countries’ GDP PPP. The association between GDP PPP and total and individual WBTi scores was analyzed using linear regression. Subsequently, data on EBF, BF1h, and continued BF from 63 countries were obtained from household surveys and other national nutrition surveys involving children under two years of age. Data on breastfeeding policies and programs were obtained from the WBTi and countries’ economic classifications from the World Bank. Associations between WBTi scores and breastfeeding indicators were analyzed using beta regression. Finally, the third objective was operationalized through a cross-sectional study using EBF and mixed BF data from DHS (Demographic and Health Surveys) and MICS (Multiple Indicator Cluster Surveys) surveys involving children under six months of age. Data on breastfeeding policies and programs were obtained from the WBTi. Time 1 (T1) corresponded to the 2000s and Time 2 (T2) to the 2020s. Multilevel logistic regression evaluated associations between WBTi scores and the outcomes EBF and mixed BF.

Results: Analysis of 98 high-, middle-, and low-income countries identified the highest mean WBTi scores for health care systems and nutrition support (indicator 5) (6.4±2.0) and information support (indicator 7) (6.4±2.5). Mean total scores and scores for indicators 3 (Code implementation), 7 (information support), 9 (infant feeding during emergencies), and 10 (monitoring and evaluation) were higher in low- and middle-income countries, whereas indicator 4 (maternity protection) presented higher mean scores in high-income countries (p<0.05). A negative association was observed between GDP PPP and the total WBTi score (β=-2.67; 95%CI:-5.06;-0.29), indicator 3 (Code implementation) (β=-0.50; 95%CI:-0.91;-0.08), indicator 7 (information support) (β=-0.67; 95%CI:-1.07;-0.27), indicator 8 (infant feeding and HIV) (β=-0.59; 95%CI:-1.07;-0.11), and indicator 9 (infant feeding during emergencies) (β=-0.91; 95%CI:-1.34;-0.48). A positive association was observed between GDP PPP and indicator 4 (maternity protection) (β=0.63; 95%CI:0.24;1.02).

In the second article, upper-middle-income countries presented lower mean EBF prevalence (37.9±2.9). Upper-middle-income (40.9±3.9) and high-income countries (26.3±9.9) showed lower mean continued BF prevalence. Countries with higher scores for indicator 8 (infant feeding and HIV) presented higher EBF prevalence (β=7.7; 95%CI=1.6;13.7). Countries with higher scores for indicator 2 (BFHI) (β=4.2; 95%CI=3.2;11.6) and indicator 3 (Code implementation) presented higher prevalence of continued BF.

In the third article, at T1, maternal age (OR=0.68; 95%CI:0.58–0.79), total WBTi score (OR=0.99; 95%CI:0.98–0.99), indicator 1 (policy and funding) (OR=0.87; 95%CI:0.85–0.89), and indicator 5 (health care systems and nutrition support) (OR=0.81; 95%CI:0.78–0.84) were negatively associated with EBF, whereas BF1h (OR=1.24; 95%CI:1.14–1.34), indicator 2 (BFHI) (OR=1.12; 95%CI:1.09–1.16), and indicator 4 (maternity protection) (OR=1.06; 95%CI:1.02–1.10) were positively associated with EBF.

At T2, female sex (OR=1.08; 95%CI:1.01–1.16), BF1h (OR=1.16; 95%CI:1.08–1.24), and indicator 1 (policy and funding) (OR=1.04; 95%CI:1.02–1.07) were positively associated with EBF, whereas maternal age (OR=0.80; 95%CI:0.70–0.92), indicator 2 (BFHI) (OR=0.91; 95%CI:0.89–0.94), and indicator 4 (maternity protection) (OR=0.89; 95%CI:0.86–0.91) were negatively associated. For mixed BF, at T1, maternal age (OR=1.68; 95%CI:1.37–2.06), indicator 1 (policy and funding) (OR=1.21; 95%CI:1.18–1.25), and indicator 5 (health care systems and nutrition

support) (OR=1.32; 95%CI:1.26–1.39) were positively associated, whereas BF1h (OR=0.73; 95%CI:0.66–0.81), indicator 2 (BFHI) (OR=0.86; 95%CI:0.83–0.87), indicator 4 (maternity protection) (OR=0.86; 95%CI:0.82–0.91), and the total WBTi score (OR=1.02; 95%CI:1.02–1.03) were negatively associated with mixed BF.

At T2, maternal age (OR=1.32; 95%CI:1.10–1.58), cesarean section (OR=1.38; 95%CI:1.22–1.57), and indicator 9 (infant feeding during emergencies) (OR=1.05; 95%CI:1.03–1.08) were positively associated with mixed BF, whereas BF1h (OR=0.71; 95%CI:0.64–0.78), indicator 3 (Code implementation) (OR=0.87; 95%CI:0.83–0.92), and indicator 5 (health care systems and nutrition support) (OR=0.95; 95%CI:0.92–0.99) were negatively associated.

Conclusion: Countries with lower GDP PPP presented higher WBTi scores, except for the maternity protection indicator, which showed higher scores in countries with higher GDP PPP. Countries with higher WBTi scores presented higher breastfeeding prevalence. Wealthier countries showed lower EBF and continued BF rates compared to poorer countries. Countries with higher scores for BFHI implementation (indicator 2), implementation of the International Code of Marketing of Breastmilk Substitutes (indicator 3), and development of infant feeding and HIV policies (indicator 8) presented higher prevalence of EBF and continued BF. BF1h was identified as a protective factor for EBF and as a reducing factor for mixed BF, regardless of the analyzed period. Older maternal age and cesarean section appeared to act as barriers to EBF. Infant feeding during emergencies may favor the adoption of mixed BF, whereas strengthening regulatory measures related to Code implementation may contribute to reducing mixed BF. The positive association between total WBTi score and mixed BF suggests that advances in breastfeeding promotion and support may contribute to maintaining breastfeeding, even if not exclusively.