Presentation (CTI)

OBJECTIVES: FXS, the leading inherited cause of intellectual disability and most common single-gene cause of autism, has greater severity in males (M). We characterize healthcare resource use (HCRU) of M and females (F) with FXS across ages, a gap no study addressed.
METHODS: The study used Symphony, a large US open claims database. HCRU was assessed cross-sectionally from 07/2022 to 06/2024 among patients aged <65y in 2023 having ≥2 claims with FXS diagnosis codes from 2019 to 2024 (FXS sample). All-cause HCRU (inpatient [IP], emergency department [ED], outpatient) and FXS-specific HCRU (e.g., medications referenced in FXS literature) were described separately for M and F across age groups: 0-12y, 13-21y, 22-25y, and 26-64y in 2023.
RESULTS: The FXS sample included 6,966 patients (70% M; 42% children ≤21y). All-cause HCRU was numerically lower in M than F across age groups driven by IP and ED visits, with small sex differences in childhood, and larger sex differences in adulthood that peaked at 22-25y (M vs F in 0-12y, 13-21y, 22-25y, and 26-64y: 4 vs 5%, 5 vs 7%, 5 vs 17%, and 9 vs 13% with ≥1 IP admission; 25 vs 28%, 22 vs 25%, 20 vs 42%, and 24 vs 30% with ≥1 ED visit. In contrast, psychotropic medication use was numerically higher in M than F across all age groups (ranges across all age groups: 54-74% vs 44-63%).
CONCLUSIONS: M with FXS had lower IP and ED utilization than F with FXS, particularly during the transition to adulthood, despite M typically presenting with more severe FXS manifestations. Limited communication abilities, institutionalized living arrangements, and loss of school structure may contribute to lower HCRU in M with FXS during the transition to adulthood as well as higher psychotropic use. Further research should include healthy controls and investigate the underlying reasons for the observed differences in HCRU.