B39-16 Prevalence of Refractory Chronic Cough and Unexplained Chronic Cough in Older Adults (≥65YEARS) Based on a Claims Algorithm Using Medicare Fee-For-Service Administrative Claims Data

Abstract Rationale Approximately 5.0% of the US population has chronic cough (CC). Refractory chronic cough (RCC) is a disease identified in a subset of people with CC that persists 8 weeks despite adequate treatment for known cough-related etiologies. Unexplained chronic cough (UCC) is diagnosed when an underlying condition is not determined despite adequate diagnostic testing. The average age of patients diagnosed with RCC/UCC is 56.9 years. Currently, no data exists on the prevalence of RCC/UCC in the US. In the absence of a specific ICD-10 code for the condition, the CC code R05.3 (introduced in 2021) encompassing persistent CC, RCC, and UCC is broadly used, making it difficult to accurately identify patients with RCC/UCC in real-world claims data. The CleaR-CC algorithm was developed (using a targeted literature review and input from a global panel of cough experts) to identify RCC/UCC patients in claims data in the absence of an ICD-10 code. Here, the objective was to apply the CleaR-CC algorithm to Medicare Fee-for-Service (FFS) data to estimate the prevalence of RCC/UCC among older adults. Methods The CleaR-CC algorithm was applied to Medicare FFS claims data from 2016-2023. Eligible patients were aged ≥65 years at the time of RCC/UCC identification and had ≥2 years of continuous enrollment. Patients with pre-existing lung conditions, recent use of ACE inhibitors, recent respiratory tract infections, or uncontrolled asthma were excluded. Descriptive analyses of patient characteristics were conducted, and annual RCC/UCC prevalence was calculated. Sensitivity analyses were performed to assess variations in RCC/UCC definition using the R05.3 code. Results From 2018-2023, 362,773 patients aged ≥65 years with RCC/UCC were identified using the CleaR-CC algorithm. The majority were female (67.3%) and White (83.2%), with a mean (SD) age of 77.5 (7.9) years. In 2023, the overall prevalence of RCC/UCC was 1.44%. Prevalence results, stratified by age, are summarized in the table. Conclusions The CleaR-CC algorithm enabled estimation of RCC/UCC prevalence in older adults in Medicare FFS data and is the first published prevalence data in the US. The RCC/UCC patient demographics identified through the CleaR-CC algorithm are consistent with those reported in the literature, supporting the algorithmic approach. The low prevalence of RCC/UCC was expected, given that diagnosis is by exclusion and the recent introduction of the R05.3 code. Future studies will validate the claims-based algorithm to accurately identify cases of RCC/UCC. This abstract is funded by: GSK study 223232