Costs of oxygen therapy for interstitial lung disease and chronic obstructive pulmonary disease: A retrospective study from a universal healthcare system

Abstract RATIONALE & OBJECTIVES: Oxygen is prescribed for patients with interstitial lung disease (ILD) and chronic obstructive pulmonary disease (COPD). This study compared the per capita financial costs of home oxygen therapy in ILD and COPD. METHODS Adults with either ILD or COPD who initiated home oxygen between 2010-2017 at the Vancouver Coastal Health Home Oxygen Program were analyzed retrospectively using a chart review. The monthly cost of oxygen equipment, home visits by oxygen providers and respiratory therapists, as well as overnight oximetry studies, were collected for each year of oxygen utilization, adjusted to 2018 Canadian Dollars. The Wilcoxon Rank Sum Test was used to compare monthly oxygen costs and flow rates between the two diseases. MEASUREMENTS AND RESULTS: A total of 99 patients with ILD and 1017 with COPD initiated oxygen therapy between 2010-2017. Both cohorts had a higher per capita cost of home oxygen in month 1 compared to months 2-24 (ILD: ($202.57 ± $88.88 versus $142.21 ± $59.01, P < 0.001; COPD: $222.85 ± $102.52 versus $156.65 ± $60.50, P < 0.001). COPD was more costly after the initial month, corresponding to greater frequency of using continuous long-term oxygen compared to oxygen only with ambulation. Patients with ILD had higher mean ambulatory oxygen flow rate for all months (P < 0.001). CONCLUSION Per capita costs of home oxygen therapy were comparable between ILD and COPD, with the main difference in costs related to the use of ambulatory versus continuous long-term oxygen. These findings will aid healthcare budget planning for both ILD and COPD.