Abstract Rationale Any-cause hypercapnic respiratory failure is common and carries high risks of readmission and death. Prior studies have quantified device-related costs in select groups, such as those treated with noninvasive ventilation. However, the broader payer-level spending associated with hypercapnic respiratory failure before, during, and after hospitalization remains undescribed. This gap limits understanding of the overall disease burden and opportunities for cost-effective intervention. Methods We performed a retrospective cohort study using linked Intermountain Health electronic health records and SelectHealth (Intermountain’s insurance arm) claims from 2016 to 2024. We included adults continuously enrolled in SelectHealth for at least one year before and after their first qualifying hospitalization. A hospitalization qualified if it met at least one criterion for hypercapnic respiratory failure: an International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) diagnosis code for hypercapnic respiratory failure of any chronicity (J96. *2) or obesity hypoventilation (E66. 2) ; an arterial blood gas with PaCO2 ≥ 45 mm Hg; or a venous blood gas with PCO2 ≥ 50 mm Hg. We calculated plan-paid, per-member-per-month (PPPM) spending and grouped costs into predefined service lines relevant to hypercapnia: inpatient (e. g. , ICU care), ambulatory (e. g. , pulmonary, sleep medicine, cardiology), and pharmacy expenditures. Results Among 170, 046 hospital admissions, 3. 3% (n = 5, 624) represented first hospitalizations meeting at least one hypercapnic respiratory failure definition (ICD-coded = 516; ABG-defined = 3, 589; VBG-defined = 1, 519). Per-member spending during the index hospitalization month averaged 50, 084, driven primarily by inpatient costs (42, 155). Baseline spending was already high (4, 256 per month over the preceding year), increased in the 3 months preceding the index event (6, 311 per month), and remained elevated for several months afterward (6, 121 per month in the subsequent 3 months). Trends by service type (inpatient, ambulatory, and pharmacy) are displayed in Fig 1B-D. Discussion Hospitalizations for hypercapnic respiratory failure incur exceptionally high acute costs, compounding already elevated baseline utilization. The measurable rise in spending before admission suggests a modifiable risk window for earlier intervention. Future studies should test whether proactive identification and post-acute care strategies can change these cost trajectories and reduce readmissions. This abstract is funded by: Intermountain Foundation
Locke et al. (Fri,) studied this question.