OBJECTIVES : Achondroplasia is a rare, genetic disorder of skeletal dysplasia with an estimated birth prevalence of 4 per 100,000 in North America. People with achondroplasia often experience complications requiring hospitalizations. Our objective was to estimate the cost of hospital admissions for people with achondroplasia in the US.

METHODS : Using 2017 data from the National Inpatient Sample, hospital admissions with a discharge diagnosis consistent with achondroplasia (ICD-10-CM code: Q77.4) in any diagnosis position were identified. Descriptive, weighted measures, including patient characteristics, length of stay (LOS), and inpatient hospital costs were reported. Costs were estimated using charges for each hospitalization and the cost-to-charge ratio included in the NIS.

RESULTS : There were 1,985 admissions of people with achondroplasia nationwide (1,080 adults and 905 children). Mean (95% confidence interval [CI]) age was 26.8 (24.0-29.6) years. About one-third (30.6% [24.4%-36.7%]) of the adults were 31-49 years and majority (69.1% [61.4%-76.8]) of the children were 0-4 years. Medicare was the primary payer for adults (45.4% [38.6%-52.2%]), and Medicaid for children (49.7% [41.6%-57.8%]). The average hospital LOS was 6.8 (5.7-8.0) days, with 6.6 (5.5-7.7) for adults and 7.1 (5.0-9.2) for children. Total mean (95% CI) inpatient costs were $19,959 (16,801-23,118), with $18,224 (15,157-21,292) for adults and $22,031 (16,311-27,752) for children. The total hospital cost was $19.7 million for adults and $19.9 million for children. Among admissions with a primary procedure reported, 19.6% were on the spine, 10.9% on the extremities, 6.8% on the head and neck, 3.0% on the brain, and the remainder on other body parts.

CONCLUSIONS : Despite the rarity of the condition, the burden of hospitalization alone is high, with total cost of approximately $40 million in 2017. Compared to a hospitalization in a general population, the average LOS was 2.2 days longer and the mean inpatient costs were $7,789 higher for people with achondroplasia.