Breastfeeding practices for infants with inherited metabolic disorders: A survey of registered dietitians in the United States and Canada

BACKGROUND: Breast milk is considered the optimal first food for infants. Breastfeeding infants with inherited metabolic disorders (IMDs) is complex due to the critical need to manage intake of specific macronutrients depending on the type of IMD. OBJECTIVE: To describe current practices of registered dietitians (RD) who treat patients with IMDs regarding the incorporation of breastmilk into disease management. DESIGN: Cross-sectional survey. Participants/setting: online survey conducted in December 2020 of 66 RDs who treat patients with IMDs in the United States and Canada. Main outcome measures: the survey focused on personal demographics, clinic characteristics, institutional feeding protocols for infants with IMDs, confidence in working with breastfeeding parents of infants with IMDs, and knowledge about breastfeeding with questions derived from the Iowa Infant Feeding Attitudes Scale. Statistical analysis performed:. Fisher's exact test was used for comparisons. RESULTS: Most RDs were confident or very confident in their ability to provide nutritional guidance for breastfeeding infants with IMDs. Half of the participants reported that they had received training on breastfeeding of infants of IMDs. For infants with phenylketonuria (PKU), most RDs include breastfeeding as part of nutritional management. Breastfeeding is less likely to be used in the management of infants with other aminoacidopathies and fatty acid oxidation disorders. Use of measured expressed breastmilk was preferred, including for aminoacidopathies other than PKU, organic acidemias, and fatty acid oxidation disorders. Knowledge about breastfeeding varied. Less than half of RDs referred mothers to a lactation specialist somewhat regularly or frequently. CONCLUSIONS: Our survey found variation in experience, training, and use of breastfeeding-related nutritional management protocols in IMDs. A lack of formal training programs for the nutritional management of IMDs may account for some of this variation. Future research, including the collection of more detailed disorder-specific data, could help contribute to the development of clinical practice guidelines.