The economic burden of spinal muscular atrophy

Abstract

Aim: To evaluate the economic burden of spinal muscular atrophy (SMA).

Materials and methods: This study used Department of Defense Military Healthcare System (MHS) data from 2003–2012. Healthcare costs were determined for patients with at least one inpatient or three outpatient claims with a diagnosis of SMA before 18 years of age and who had ≥ 6 months of data after first SMA diagnosis or expired within 6 months of initial diagnosis. A comparator cohort was selected using a 3:1 match based on age and gender.

Results: A total of 239 individuals with SMA diagnosis met the inclusion criteria along with 717 matched comparator patients. More patients with SMA had hospitalizations (69.5%) compared to the comparator cohort (17.2%, p < 0.001). Median total expenditures across all years of data for patients with SMA were $83 652 (25–75th percentile = $29 620–228 754) vs the comparator group of $4329 (25–75^th percentile = $1229–10 062 (p < 0.001)) over an average (SD) of 6.9 ± 3.6 years. The annualized mean costs of total healthcare expenditures were significantly higher for the SMA cases than the comparison cohort, $47 862 ± 88 607 compared to $1861 ± 6374, respectively (p < 0.001). The sub-group of patients with early diagnosis (n = 45) had 4.3 ± 2.9 years of observation with a median cost of $167 921 ($53 349–678 412). Mean age (SD) at first observed SMA diagnosis was 7.5 ± 6.4 years. Mean (SD) duration of follow-up after initial SMA diagnosis was 4.8 ± 3.3 years, with a median post-diagnosis cost of $60 213 ($18 229–192 559). The major costs for all patients were outpatient visits [median = $53 152 ($23 902–136 150)], followed by inpatient costs [median = $11 258 ($0–51 987)] and total prescription costs [median = $3167 ($943–13 283)].

Limitations: The analysis is limited to the data available and may under-estimate the total cost of SMA.

Conclusions: Individuals with SMA have a high degree of morbidity, particularly those diagnosed during infancy. SMA patients have significant medical expenditures and high utilization of healthcare services.

Keywords:

• Spinal muscular atrophy
• Neuromuscular disease
• Muscle disease

Transparency

Declaration of funding

This study was funded by Biogen to Strategic Therapeutics, LLC.

Declaration of financial/other interests

EPA and DCM were consultants to Biogen through Strategic Therapeutics, LLC for this project. WSY is an employee of and has stock options with Biogen. NS is an employee of Health ResearchTx LLC, which has a business agreement with Biogen. JME peer reviewers on this manuscript have no relevant financial or other relationships to disclose. Research data derived from an approved Naval Medical Center, Portsmouth, VA IRB protocol. Dr Dahl and Dr. Lee are military service members. This work was prepared as part of their official duties. Title 17 U.S.C. 105 provides that “Copyright protection under this title is not available for any work of the United States Government”. Title 17 U.S.C. 101 defines a United States Government work as a work prepared by a military service member or employee of the United States Government as part of that person’s official duties. The views expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the Department of the Navy, Department of Defense or the United States Government.

Previous presentation

This study was presented as a poster presentation at the International Society for Pharmacoeconomics and Outcomes Research, Philadelphia, PA, May 20, 2015.

Acknowledgement

The authors would like to thank the Navy and Marine Corps Public Health Center for its support during the conduct of this study.