ESPE Abstracts

Background: Achondroplasia is the most common skeletal dysplasia associated with inhibited growth development and disproportionately short stature; morbidity and complications are apparent at birth and continue throughout life. We assessed the clinical and healthcare resource utilization (HCRU) burden of achondroplasia in US children and adolescents.

Methods: This retrospective study assessed children and adolescents (aged <18 years) with ≥1 inpatient claim, or ≥2 distinct claims in any other setting, with achondroplasia ICD-10 diagnosis codes in Optum’s de-identified Clinformatics^® Data Mart Database administrative US claims database (01-Oct-2015 to 01-Oct-2023). Index was date of first achondroplasia ICD-10 code, and ≥12 months of subsequent continuous enrollment was required. All-cause HCRU (outpatient, emergency room [ER], inpatient, intensive care unit [ICU], and non-ICU inpatient visits) was assessed in patients with achondroplasia versus controls (matched 1:5 on age, sex, and index date). Means and proportions were compared using t-tests and Chi-square tests, respectively. Results from an adult cohort (≥18 years at index) are also presented for comparison.

Results: Overall, 241 children and adolescents with achondroplasia were matched with 1205 controls (mean [SD] age was 7.9 [5.4] years and 51.3% were female in both cohorts; 54.4% vs 48.2% were white). Mean (SD) follow-up was 40.2 (24.4) months in achondroplasia patients versus 41.5 (24.0) months in controls; mean (SD) Charlson comorbidity index was 0.3 (0.7) versus 0.2 (0.5), respectively. Rates of comorbidities during follow-up appeared higher in the achondroplasia cohort versus controls across multiple domains, including otorhinolaryngology, musculoskeletal, and pain comorbidities. HCRU encounters were higher in achondroplasia patients versus controls, with more frequent outpatient (100.0% vs 99.3%; P = 0.3696), ER (43.2% vs 36.7%; P = 0.0688), inpatient (36.9% vs 15.4%; P <0.0001), ICU inpatient (12.0% vs 0.8%; P <0.0001) and non-ICU inpatient (31.1% vs 15.0%; P <0.0001) visits. Results were similar when comparing adult cohorts (Table).

Conclusion: Achondroplasia incurs substantial clinical and healthcare resource burden in children and adolescents receiving care in US clinical practice, and this burden remains considerable in adults. The impact of disease-modifying therapies on these outcomes remains to be determined.