TYPE II INFLAMMATION IN PATIENTS WITH COPD TAKING PROTON PUMP INHIBITORS

Abstract

TOPIC: Obstructive Lung Diseases TYPE: Original Investigations PURPOSE: To examine if (chronic obstructive pulmonary disease) COPD patients taking proton pump inhibitors (PPI's) are more likely to be admitted and if a significant difference in eosinophil levels exist when compared to COPD patients not taking PPI's. METHODS: A retrospective case control analysis comparing clinically diagnosed COPD patients on PPI's to those who were not in terms of demographics, spirometry, eosinophilia, and admissions. We considered p<0.05 statistically significant. Risk factors for admissions were sought using both univariate and multivariate analyses. They were selected for a multivariate analysis if their p<0.05 or if clinically significant. RESULTS: A total of 314 clinically diagnosed COPD patients had obstruction on PFT's, completed a CBC with differential and met our matching algorithm. Baseline characteristics showed no significant difference between the PPI and non-PPI groups in; percent predicted FEV1(PPI 46.8 non-PPI 46.5 p=0.917), FEV1/FVC(PPI 45.5 non-PPI 45.2 p=0.795), age(PPI 68.4 non-PPI 68.8 p=0.695), male gender(PPI 75/157 non-PPI 75/157 p=1.0), BMI(PPI 28.0 non-PPI 26.6 P=0.079) and smoking history(PPI 84/157 non-PPI 79/157 p=0.572).A significant difference was found between the PPI and non-PPI groups in eosinophil %(E%) (PPI 3.6 non-PPI 3.0 p=0.008), maximum eosinophil count(MEC) (PPI 0.300K/µL non-PPI 0.244K/µL p=0.008), being above the GOLD eosinophil benefit threshold(GEBT) (PPI 74/157, non-PPI 52/157 p=0.011), and admissions(PPI 46/157, non-PPI 26/157 p=0.007).Using admission as the outcome variable, the following variables were significant in a univariate analysis: PPI use(Admitted 46/72 not 111/242 p=0.01), MEC(Admitted 0.333K/µL Not 0.254K/µL p=0.018), E%(Admitted 3.8 Not 3.2 p=0.037), GEBT(Admitted 37/72 Not 89/242 p=0.029), age(Admitted 65.9 Not 69.4 p=0.011), history of smoking(Admitted 45/72 Not 118/242 p=0.044). In our multivariate model PPI use(p=0.019, OR=1.96), GEBT(p=0.041 OR 1.78) and age(p=0.034 OR=0.97) were significant while smoking history(p=0.079 OR 1.65) and FEV1(p=0.287 OR 0.991) were not. CONCLUSIONS: Our study was the first to show a significant difference with higher blood eosinophil levels in COPD patients on PPI's versus not taking PPI's. We also found PPI's were associated with admissions. While PPI's are an effective treatment for GERD, reflux likely still occurs due to changes in pressure dynamics augmented in COPD. In addition, during reflux a vagally mediated acid induced bronchospasm reflex may be triggered by the presence of acid in the esophagus. This reflex persists even after acid clearance and is thought to initiate an inflammatory cascade and bronchospasm. Our findings suggest this inflammation may be eosinophilic in nature and warrants further research evaluating eosinophilia in COPD patients with GERD. CLINICAL IMPLICATIONS: COPD patients on PPI's are more likely to be admitted and to have higher eosinophil levels. DISCLOSURES: Grant for research relationship with Sanofi Please note: January 2021 Added 04/20/2021 by Daniel Ouellette, source=Web Response, value=Grant/Research No relevant relationships by Jovica Veljanovski, source=Web Response