OBJECTIVES: AADC deficiency is a rare condition, with 30 new cases estimated per year in the US. Many individuals are severely delayed in reaching developmental milestones and rely on their caregivers for all aspects of daily living. The objective of this study was to estimate the costs related to caring for individuals with AADC deficiency in the US.

METHODS: A model was built to estimate the annual costs associated with caring for individuals with AADC deficiency, using data provided by US caregivers (i.e. time spent caring, amount of paid and/or unpaid help received, and the impact on employment). Cost inputs were derived from public sources.

RESULTS: Seven US caregivers completed the questionnaire and reported an average of 111 (range: 84-147) hours/week spent on practical and emotional care for their child, plus a mean of 16 (range: 12-22) hours/week on administrative tasks and travelling/attending medical appointments. 14% (1/7) received unpaid support provided by the partner (12 hours/week) and 43% (3/7) of caregivers had stopped working. With expected 30 new patients and their families in the country, the total number of hours needed for informal care was 200,741 annually, which corresponds to $5.4 million for informal care. Hours of loss of productivity were estimated to be 17,206 annually, leading to an estimated $466,000 of family income loss.

CONCLUSIONS: Primary caregivers spent almost every waking moment caring for the individual with AADC deficiency, requiring almost half to stop working and resulting in substantial annual indirect costs. Caregiver who hadn’t changed their work, but were already full-time homemakers were not included in the calculations, neither were direct medical and nonmedical costs i.e. underestimating the overall economic impact of AADC deficiency. These findings highlight the importance of considering the caregiver impact when evaluating the burden of disease.