Endocrine Abstracts

JOINT1326

Introduction: Rare bone diseases pose challenges for both affected people and healthcare systems, necessitating optimized multidisciplinary and individualized care. However, comprehensive data on age-specific hospitalization rates, associated clinical conditions, causes of hospitalization, and in-hospital outcomes across different age groups remain limited.

Design and Methods: This is a population-based nationwide cohort study using administrative claims data from Switzerland between January 1, 2012, and December 31, 2021. We identified individuals across all ages with a diagnosis of a rare bone disease: Achondroplasia, fibrous dysplasia (FD), fibrodysplasia ossificans progressiva (FOP), osteogenesis imperfecta (OI), pseudohypoparathyroidism, and X-linked familial hypophosphatemia (XLH). Incidence rates, main causes of hospitalization, and in-hospital outcomes were assessed and compared with those of the general population.

Results: Among 11, 103, 800 hospitalizations, 2, 878 involved individuals with at least one rare bone disease: 218 hospitalizations of people with achondroplasia, 436 with FD, 62 with FOD, 926 with OI, 87 with pseudohypoparathyroidism, 1, 148 with XLH, and one individual with both FD and pseudohypoparathoyroidism. Hospitalizations were disproportionately high in pediatric patients (ages 0-17 years) with achondroplasia (52. 1% vs. 7. 3% in the general population) and OI (41. 1% vs. 7. 3%). In contrast, most hospitalizations of people with XLH occured in adulthood (18-90 years), similar to the general population (95. 2% vs. 92. 7%). Locally estimated scatterplot smoothing (LOESS) plots highlight distinct hospitalization patterns across rare bone diseases, with fractures being a significantly more common cause, particularly in pediatric OI cases.

Conclusions: This study shows distinct age-specific hospitalization patterns across rare bone diseases, emphasizing the need for tailored management strategies. The findings highlight the importance of an age-inclusive approach to optimize care in this population.