PURPOSE:Long-term oxygen therapy (LTOT) decreases mortality and may reduce the risk for exacerbation-related hospitalizations in patients with COPD. While the recommendation to prescribe oxygen at rest, exercise, and sleep is widely known, the actual use is less clear. We sought to determine if oxygen is utilized in Colorado COPD patients according to standards for initiation and titration of oxygen therapy set forth by the Nocturnal Oxygen Therapy trial (NOTT), the Medical Research Council (MRC) study, and the Global Initiative for Obstructive Lung Disease (GOLD).
METHODS:GOLD stage 3 or 4 COPD patients (n=511) were enrolled in an IRB approved COPD trial from a variety of medical settings in Colorado. Oxygen saturations (SpO2) were measured at rest and following a 6-minute walk test by oximetry. For analysis, subjects were divided into LTOT-treated cohorts (n=417) and non-treated cohorts (n=94) to determine the extent to which oxygen was under-titrated or under-prescribed.
RESULTS:The overall study population had the following characteristics: age=68, FEV1=37% predicted, SGRQ=48 and BODE index=4.8. Of the LTOT-treated cohort, 7.9% had a resting SpO2 less than the standard therapeutic goal of 90% and 59.2% had a post-exercise SpO2 < 90%. Of the untreated cohort, 2.1% had a resting SpO2 of ≤; 88% and 43.6% had a post-exercise SpO2 of ≤; 88%.
CONCLUSION:Almost half of the patients in our cohorts were not on adequate oxygen therapy despite clinical indication. These results suggest that oxygen is under-prescribed and inadequately titrated to meet established goals in COPD-related hypoxia. Additionally, a large percentage of patients in both cohorts demonstrated suboptimal post-exercise SpO2 measurements, implying an under-appreciation of exercise-induced hypoxia.
CLINICAL IMPLICATIONS:The prevalence of untreated exercise-induced hypoxia is potentially high in patients with COPD. Further investigation is needed into improving provider awareness, detection, and treatment of COPD-related hypoxia. Additionally, how the inadequate use of LTOT affects the overall health, and healthcare utilization, of this population is also an area warranting further investigation.
DISCLOSURE:Jason McCarl, No Financial Disclosure Information; No Product/Research Disclosure Information