The financial and time burden associated with phenylketonuria treatment in the United States

Phenylketonuria (PKU) imposes a substantial burden on people living with the condition and their families. However, little is known about the time cost and financial burden of having PKU or caring for a child with the condition.

Primary data were collected with a detailed cost and utilization survey. Primary outcomes included utilization and out-of-pocket costs of medical services, medical formula, and prescribed low-protein food consumption, as well as the time and perceived effort involved in following the PKU diet. Respondents were people living with PKU or parents of children with PKU identified through a state newborn screening program database. Secondary administrative claims data were also used to calculate mean total, insurer, and out-of-pocket payments in inpatient, outpatient (office visits, emergency room, and laboratory tests), and pharmacy settings for privately insured persons with PKU. Payments were calculated for sapropterin and for PKU formula.In primary data analysis (children n = 32, adults n = 52), annual out-of-pocket costs were highest for low-protein foods (child = $1651; adult = $967) compared with other categories of care. The time burden of PKU care was high; families reported spending more than 300 h per year shopping for and preparing special diet foods.In secondary data analysis, children 12-17 years old had the highest average medical expenditures ($54,147; n = 140) compared to children 0-11 years old ($19,057; n = 396) and adults 18 years and older ($40,705; n = 454). Medication costs were the largest contributor to medical costs, accounting for 61-81% of total costs across age groups. Sapropterin was the largest driver of medication costs, accounting for 85% of child medication costs and 92% of adult medication costs.

Treatment for PKU incurs a substantial time and cost burden on persons with PKU and their families. Estimated medical expenditures using claims data varied by age group, but sapropterin represented the largest cost for PKU treatment from a payer perspective across age groups.