HIV infection and breast-feeding: policy implications through a decision analysis model

Abstract

Objectives: (1) To develop a comprehensive decision analysis model to compare mortality associated with HIV transmission from breast-feeding with the mortality from not breast-feeding in different populations and (2) to perform sensitivity analyses to illustrate critical boundaries for guiding research and policy.

Methods: Using a decision tree, mortality rates were estimated for all children, children born to mothers infected during pregnancy, and children born to mothers who were uninfected at delivery. Given various assumptions about child mortality rates, relative risks of mortality among children who are not breast-fed compared with those who are (R), rates of HIV transmission from breast-feeding, HIV prevalence, and HIV incidence, scenarios were created and sensitivity analysis used to delineate critical boundaries.

Results: Our model shows that only in situations where R is approximately < or = 1.5 and HIV incidence/prevalence is high (prevalence > 10%, incidence > 5%) would universal breast-feeding result in equal or higher mortality compared with non-breast-feeding. Among populations in many developing countries, where there is a high relative risk of mortality if breast-feeding is not practiced, if R > 3, overall mortality is almost always lower among children who are breast-fed, even by HIV-infected mothers. In situations where maternal HIV status is known, the decision whether to breast-feed is largely dependent on the magnitude of additional mortality risk if the child is not breast-fed. The model illustrates the importance of distinguishing between population and individual recommendations.

Conclusions: Based on available data, the model supports current World Health Organization and Centers for Disease Control recommendations on HIV infection and breast-feeding. Given the importance of breast-feeding and the global impact of HIV infection, more research is needed, especially to clarify the range of HIV transmission rates from breast-feeding and to expand specific assessments of relative risks for different areas of the world.

PIP: HIV/AIDS specialists have developed and applied 3 different scenarios to a comprehensive decision analysis model to estimate mortality rates for children of mothers infected with HIV during pregnancy and for children of mothers who were not infected with HIV during delivery. Scenario I represents Central Africa where HIV prevalence and incidence are high. Some scenario I assumptions are HIV prevalence in pregnant women of 30% and proportion of initially uninfected women who become infected after delivery during lactation (d) of 6%. Scenario II is a population where HIV epidemic is rather recent (e.g., some parts of Asia). Its assumptions are HIV prevalence of 5%, and s is 2%. Scenario III symbolizes high-risk populations in North America and Western Europe (HIV prevalence and s = 1%). The scenarios also consider child mortality rates and relative risks (RRs) of mortality of breast fed children and those who were not breast fed. Universal breast feeding would effect equal or higher mortality than non-breast feeding, when the RR of mortality is no more than 1.5 and HIV prevalence/incidence is high (high prevalence = 10% and high incidence = 5%). In developing countries, where the RR of mortality is high if children are not breast fed (RR 3), breast fed children have almost always lower child mortality than those who are not breast fed, regardless of HIV infection status. The decision to breast feed when the HIV status is known depends greatly on the degree of an additional mortality risk if an infant is not breast fed. The model substantiates WHO and CDC recommendations: HIV-positive women in the UK and the US should not breast feed, while those in developing countries with high RR of child mortality should breast feed. Additional research would define the range of HIV transmission rates from breast feeding and increase specific assessments of RRs for various parts of the world.