Professional Abstract
Objective
To evaluate the effect of supplemental oxygen on breathing and physical activity in patients with pulmonary fibrosis (PF) by comparing dyspnea, quality of life, and patient and caregiver perceptions of oxygen use before and after treatment
Study Design
Design Element |
Description |
Design |
Longitudinal mixed-methods study |
Population |
- Quantitative study: 43 patients with PF who received supplemental oxygen prescriptions
- Qualitative study: 5 of the 43 patients with PF who received supplemental oxygen prescriptions, 20 informal caregivers
|
Interventions/
Comparators |
Supplemental oxygen use |
Outcomes |
Primary: dyspnea
Secondary: physical activity, mobility, general quality of life, fatigue, cough-specific quality of life, and patients’ and caregivers’ perceptions of supplemental oxygen use
|
Timeframe |
9-12-month follow-up for primary outcome |
In this longitudinal mixed-methods study, researchers compared outcomes in patients with PF before and after they received supplemental oxygen. Researchers had previously enrolled 300 patients with PF from across the United States in a database of potential patients for studies. For this study, the team enrolled 43 database patients who were about to begin supplemental oxygen treatment. Of the 43 patients, 93% were white, and 56% had a diagnosis of idiopathic PF.
The research team collected surveys and activity monitor data one week before patients started using oxygen and then 1 month and 9–12 months after starting oxygen. Researchers compared mean values for the three timepoints using paired t-tests. To assess outcomes over time, researchers performed slope analysis using linear mixed models using the timepoint at which the surveys were collected, forced vital capacity, age, and gender as predictors. The slope analysis used all available data rather than excluding data from patients who failed to complete one or more surveys.
Researchers also interviewed 5 patients with PF and 20 informal caregivers by phone to understand their perceptions of and experiences with supplemental oxygen. The research team conducted three interviews with the five patients when they collected survey data. The team interviewed caregivers once after patients had used supplemental oxygen for at least eight months. Researchers used grounded theory and a team analytic approach to identify themes from the interviews.
Results
- Comparisons of outcomes before oxygen use and one month after starting oxygen. Supplemental oxygen did not appear to improve dyspnea, quality of life, cough-specific quality of life, or physical activity, but it significantly improved fatigue (p=0.03).
- Comparisons of outcomes 1 month after and 9–12 months after starting oxygen. Over time, patients with PF had worse dyspnea (p=0.05), cough-specific quality of life (p=0.02), and quality of life, assessed in terms of general-health (p=0.01) and vitality (p=0.04).
- Benefits and hardships for patients with PF. During interviews, patients with PF said that they expected supplemental oxygen would improve their symptoms. Four of the five interviewed patients said they experienced the expected benefits. The hardships of oxygen use included having to carry cumbersome equipment and dealing with the social stigma of using oxygen in public.
- Benefits and hardships for informal caregivers. Caregivers felt that oxygen helped patients be more active and feel less fatigued. However, caregivers also felt that helping with the treatment increased the amount of physical work the caregivers did at home. Caregivers said that oxygen use also strained their relationships with patients.
Limitations
The study had a small number of patients and no control group. Thus, results should be considered exploratory. Most patients received care from centers of excellence; results may not be generalizable to other healthcare settings. Researchers could not confirm whether patients used oxygen as prescribed, the prescribed oxygen achieved target blood oxygen saturation levels, or patients had drug-related side effects from other medications. These actions could affect PF symptoms and patient quality of life.
Conclusions and Relevance
These results do not support or discourage the use of supplemental oxygen in patients with PF. Supplemental oxygen may improve patients’ fatigue in the short term. Physicians can discuss the benefits and hardships of supplemental oxygen use with patients and caregivers.
Future Research Needs
Future research could compare outcomes in patients with PF who use supplemental oxygen with outcomes in patients who do not.