OBJECTIVES: Glycogen Storage Disease Type Ia (GSDIa) is a rare inherited deficiency of glucose-6-phosphatase causing impaired glycogen and glucose metabolism. Patients are at risk of acute hypoglycemia and long-term renal and hepatic complications. Current management requires frequent meals and consumption of uncooked cornstarch to maintain blood glucose. Thus, patients with GSDIa require considerable healthcare resource utilization (HCRU). This retrospective cohort study assessed baseline HCRU among patients with GSDIa in the US and the impact of COVID-19.

METHODS: PearlDiver claims database with Mariner dataset was searched for patients with ≥2 GSDIa codes (ICD-10-D-E7401), no diagnoses related to inflammatory bowel disease (indicative of GSDIb), and ≥12 months continuous insurance enrollment between October 2015 and February 2020. A non-GSDIa comparator group was generated using propensity-score age- and sex-matching. To assess COVID-19 impact, matched patients with 6+ months enrollment before (March–October 2019) and during COVID-19 (March–October 2020) were compared. Setting-of-care HCRU and costs are reported.

RESULTS: Overall, 1402 patients with GSDIa and 1402 comparators (male, 64.1%; mean age, 27.2 years; mean enrollment, 3.6 years) were included. Compared with non-GSDIa comparators, patients with GSDIa had more annualized hospital admissions (0.3 vs 0.04), longer average length-of-stay per admission (8.3 vs 5.0 days), and more annualized ER (1.7 vs 0.6), outpatient hospital (6.8 vs 2.0), and physician office visits (4.8 vs 3.6). Mean (SD) annualized cost was greater for GSDIa than comparators ($19,213 [$39,082] vs $5,326 [$16,352]). In COVID-19 impact sub-analysis (n=800), patients with GSDIa had a 28.3% reduction in outpatient/physician office visits and a 31.3% reduction in ER visits/hospitalizations.

CONCLUSION: GSDIa is associated with substantial HCRU and care costs. Across all settings, patients with GSDIa had fewer healthcare visits during COVID-19 compared with the pre-COVID-19 period. Future studies are needed to assess the impact of less frequent or delayed GSDIa care due to COVID-19.