Cost-effectiveness of donor milk banking for the prevention of necrotising enterocolitis
CLAHRC WM is collaborating with the African Population Health Research Centre (APHRC) in the evaluation of donor milk banks in slums (informal settlements) in Kenya. The initiative is led by PATH, which has had considerable success in establishing an altruistic donor service in South Africa. The donor milk is donated to hospital wards caring for premature infants.
There is excellent evidence that donor human milk is superior to ‘formula’ in babies whose mothers are unable to express breast milk. As a result of passive immunity, and also because it has nutritional properties that formula is not able to replicate, donor human milk reduces the risk of neonatal infection. In particular, it reduces the dangerous condition of necrotising enterocolitis (NEC).
One concern is that the mothers of infants who receive donor milk may be less likely to initiate breast feeding at a later date for psychological or physiological reasons. The evidence does not bear out this concern and, if anything, these mothers, perhaps inspired by the altruism of the donors, are more likely to breastfeed. If so, this may be expected to augment the benefits of donor milk and also reduce the mother’s risk of developing breast cancer later in life.
The benefits do not seem to end there. There is observational evidence, recently reinforced by a substantial study from Brazil, that cognitive ability in later life is improved by human milk. There is a dose-response effect and the results remain after extensive statistical adjustment for confounders. There is also some experimental (RCT) evidence for a beneficial effect on IQ. Improved IQ is correlated with earning power and, we must assume, payback to society.
A health economic analysis of promotion of breastfeeding for older children (not premature infants specifically) found that the intervention ‘dominated’ – reduced short-term benefits (less infection) and the contingent cost savings (reduced hospital stays) meant that interventions to promote breastfeeding are cost-saving, not just beneficial for health.
There have been two studies of the cost-effectiveness of a donor milk service for premature babies. Both found that the service was cost-effective. The first study was based on a hypothetical baby who was very premature (28 weeks gestational age), rather than an observed mean intervention effect observed at the group level. The calculated benefits might therefore be exaggerated. The second study was based on only 175 propensity scored low birth weight infants. The risk of sepsis decreased with increasing dose of human milk, and total costs obtained from the hospital billing system were lower in proportion to the amount of human milk consumed. However, most infants received some human milk, so the infants could not be divided into a control and intervention population, and the above correlation between outcome and volume of donor milk consumed may have been confounded by factors that determine both access to human milk and sepsis, notwithstanding propensity scoring. Both the above studies were American.
Working with colleagues above, we propose a comprehensive health economic model that takes account of long-term outcomes and that can be populated with country-specific data. The base-case model will be populated with evidence from systematic reviews, and we propose to use Bayesian techniques to ‘down weight’ observational evidence using the Turner and Spiegelhalter method.