Abstract Rationale Gastroesophageal reflux disease (GERD) is a common comorbidity in non-cystic fibrosis bronchiectasis (NCFB), yet its impact on clinical outcomes remains poorly defined. We sought to determine whether GERD is associated with worse clinical outcomes in patients with NCFB using a large, real-world database. Methods We conducted a retrospective cohort study using the TriNetX platform, identifying patients with NCFB (ICD-10 J47*) with and without concurrent GERD (ICD-10 K21*), excluding those with cystic fibrosis (ICD-10 E84*). Propensity score matching (PSM) was performed using 1:1 nearest neighbor matching without replacement, controlling for age, sex, race/ethnicity, obesity, socioeconomic risk factors, and tobacco use. Primary outcomes included pneumonia, bronchiectasis exacerbations, intensive care unit admission, mechanical ventilation, and mortality. Statistical analyses included risk ratios and Cox proportional hazards modeling for survival outcomes. Results Out of 421,710 patients with NCFB in the dataset from January 2000 to September 2025, 186,874 (44%) had a diagnosis of GERD. After propensity score matching, 179,753 patients with NCFB+GERD and 179,753 patients with NCFB-only were included (mean age 74.0±13.1 years, 58.8% female, 67.1% White). Baseline characteristics were well-balanced after matching. Median follow-up was approximately 2.5 years for both cohorts (898 vs 889 days; similar means and IQR), ensuring balanced observation time. Compared to NCFB-only, NCFB+GERD was associated with increased risks for mortality (risk ratio 1.04, 95% CI 1.02-1.05; p 0.001), pneumonia (risk ratio 1.06, 95% CI 1.05-1.08; p 0.001), bronchiectasis exacerbations (risk ratio 1.03, 95% CI 1.01-1.06; p = 0.006), and mechanical ventilation (risk ratio 1.14, 95% CI 1.10-1.18; p 0.001). Intensive care unit admission rates were comparable between groups (risk ratio 1.00; p = 0.65). Conclusions In this large propensity score-matched analysis, concurrent GERD in NCFB is independently associated with increased mortality, pneumonia, bronchiectasis exacerbations, and mechanical ventilation requirements. These findings suggest GERD may represent a modifiable risk factor warranting aggressive management in NCFB patients. Study limitations include retrospective design, reliance on ICD-10 coding accuracy, and potential unmeasured confounders. Our results support systematic screening and treatment of GERD in NCFB, but whether targeted GERD management can modify the natural history of NCFB future investigation. This abstract is funded by: None
Daher et al. (Fri,) studied this question.