PREVALENCE OF PRISM IN SPIROMETRY DATABASE

Abstract

SESSION TITLE: Tuesday Abstract Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: 10/22/2019 01:00 PM - 02:00 PM PURPOSE: Spirometry results can yield diagnosis of normal, airflow obstruction (AFO) or Preserved Ratio Impaired Spirometry (PRISm), defined as a reduced FEV1 in the setting of a preserved FEV1/FVC ratio. Previous studies in research cohorts or general population estimated the prevalence of PRISm to be in the range of 7-14%. Our objective was to examine the prevalence of PRISm in a spirometry database and to determine if it was associated with clinical and demographic features as well as referral diagnosis. METHODS: We performed a retrospective analysis of demographic, clinical and spirometric characteristics of total of 21,870 spirometries. 1,616 spirometries were excluded because of missing data for analysis or extremes of age / height / weight. We calculated the prevalence of PRISm in prebronchodilator and postbronchodilator PFTs. Then we excluded multiple PFTs for the same individual. If there were multiple PFT sessions for a single individual, only the most recent one was included. We calculated the prevalence of PRISm in various age, race, BMI, diagnosis categories, male and females, smokers and non-smokers, Finally, in subset of cohort that included only patients with FEV1 RESULTS: We identified a total of 18,059 spirometries, 1,507 (17.7%) from these yielded diagnosis of PRISm. This prevalence remained stable when we performed subanalysis for postbronchodilator spirometries (2,031 out of 8,494 ; 20.7%), after excluding earlier PFTs for subjects with multiple PFTs (1,110 out of 4,567 ; 24.3%). It also remained stable in a subanalysis of prebronchodilator spirometries which met ATS criteria (1,342 out of 6,494 :20.6%). The PRISm prevalence was higher in 45-60 year old subjects (24.4%) compared to other age groups and in males (23.7%) vs females (17.9%) . The prevalence also rose with BMI, it was 31.7% in very obese subjects and was higher for referral diagnosis of restrictive lung disease (RLD) (50%). PRISm prevalence was similar between races and smokers vs non smokers. In multivariable analysis higher FEV1% predicted (OR 1.042, 95% CI 1.036-1.048), BMI (OR 1.04, 95% CI 1.03-1.05) and RLD (OR 4.31, 95% CI 2.54-7.57) were associated with diagnosis of PRISm. Smoking was inversely associated (OR 0.55, 95% CI 0.46-0.65) with PRISm. CONCLUSIONS: In our database the PRISm prevalence was 17-24% depending on subanalysis, which is significantly higher than the previously reported prevalence. PRISm prevalence increases with increasing BMI, lung function, and is higher in non-smokers and those with RLD. CLINICAL IMPLICATIONS: This article both shows that prevalence of PRISm is higher than previously thought and also gives insight for risk factors / associations of PRISm. This might alter and improve providers' appreciation of this diagnosis. DISCLOSURES: No relevant relationships by Nicholas Arnold, source=Web Response Consultant relationship with VIDA Diagnostics and GlaxoSmithKline Please note: $1001 - $5000 Added 03/14/2019 by Alejandro Comellas, source=Web Response, value=Consulting fee Removed 03/14/2019 by Alejandro Comellas, source=Web Response Consultant relationship with VIDA Diagnostics Please note: $1-$1000 Added 03/14/2019 by Alejandro Comellas, source=Web Response, value=software support Consultant relationship with GlaxoSmithKline Please note: $1001 - $5000 Added 03/14/2019 by Alejandro Comellas, source=Web Response, value=Consulting fee no disclosure on file for Michael Eberlein; No relevant relationships by Spyridon Fortis, source=Web Response No relevant relationships by Andrei Schwartz, source=Web Response no disclosure on file for Becky Skinner