0447 Study of PAP response and compliance in patients with ILD and OSA: A case-control single center cohort

Abstract Introduction Interstitial lung disease (ILD) is a heterogenous group of parenchymal lung disorders with multiple etiologies. ILD often affects the quality of life and survival of patients. OSA is commonly diagnosed among ILD patients with reported prevalences of 50-90%, and a prevalence of moderate to severe OSA as high as 65%. There is also concern that patients with ILD may be less tolerant of PAP therapies. We aim to identify differences in PAP treatment response and adherence in patients with ILD and OSA compared with a group of matched OSA controls. Methods A retrospective cohort analysis was conducted on patients ≥ 18 years-old that were evaluated at Mayo Clinic Center for Sleep Medicine between July 2012 to June 2022. Inclusion criteria were patients with a diagnosis of ILD per ATS criteria also diagnosed with OSA by HSAT or PSG. Control OSA patients were matched to ILD/OSA patients by age, BMI, and AHI ranges. Exclusion criteria included comorbid conditions of asthma or COPD. Patients with early non-adherence to CPAP or those who didn't have sleep follow up were also excluded. Follow-up sleep visits were assessed to determine CPAP adherence, change in PAP pressure, addition of oxygen, and change in Epworth sleepiness scale. Results We compared 51 patients with ILD/OSA and 51 OSA matched-controls. Twenty-five ILD/OSA patients were diagnosed by PSG and 26 by HSAT. Median treatment follow-up for the ILD group was 7 months (IQR of 3 to 18 months). Baseline characteristics, including oxygen desaturation index (ODI), oxygen saturation, time spent below 89% during overnight oximetry, and baseline Epworth scale, were similar between ILD/OSA and non-ILD OSA patients. Importantly, there was no statistically significant difference in PAP adherence, median PAP levels, PAP pressure change, residual AHI, or change in Epworth after treatment Conclusion There was no significant difference in baseline OSA characteristics, treatment response, and PAP adherence in ILD patients with OSA compared with matched non-ILD OSA controls. Outcome assessment may be limited by sample size and the shorter follow-up period. Future studies should include longer-term follow-up with a larger ILD cohort to assess the impact of ILD progression on PAP adherence over time. Support (if any)