Factors Influencing Risk for Developing Pneumonia Amongst Proton Pump Inhibitor (PPI) Users

Abstract

Introduction: Proton Pump inhibitors (PPIs) are widely used medication for variety of indications and generally well tolerated. Several studies have revealed the increased risk of pneumonia in patients taking PPIs. The goal of our study is to evaluate risk factors in PPI users, which can contribute to the acquisition of pneumonia. Methods: Our case-control study included 408 patients who were admitted to SUNY Upstate University hospital between Jan 2011 and Dec 2012. The cases had a primary diagnosis of community acquired pneumonia (CAP) or healthcare associated pneumonia (HCAP) with chest x-ray evidence of pneumonia and the controls had a primary diagnosis of chest pain without clinical or radiological evidence of pneumonia. The cases and the controls included subgroups of patients who used PPI vs. those who did not. Patients aged 18 years and above were enrolled. Data collection was performed using electronic medical records. Statistical analysis was performed using MS Excel and SPSS V.17 including descriptive statistics. Results: A total of 408 patients (cases 166 and 242 controls) were enrolled in the study. Out of all patients on PPI, 45% patients were started on PPI for stress ulcer prophylaxis. There was no difference between M: F ratio or average age between 2 groups. We found that PPI users have higher risk of acquiring pneumonia (OD - 1.5, P - 0.03). Smokers have higher risk of pneumonia while on PPI as oppose to those not on PPI (OR - 2.62, P - 0.009). Patients with GERD have higher risk of pneumonia while on PPI (OR - 1.80, P - 0.03). Patients with cancer who are on chemotherapy have higher risk of pneumonia while on PPI as compared to those who are not on PPI (OR - 4.2, OR - 0.0001). Use of statin reduces risk of pneumonia among PPI users (OR - 0.46, P - 0.01). History of Diabetes, heart failure, stroke, cirrhosis, Use of ACE inhibitors or systemic steroids did not influence risk of acquiring pneumonia while on PPI. Conclusion: We conclude that use of PPI does increase the risk of acquiring pneumonia. The factors leading to this enhanced risk are smoking, diagnosis of GERD, cancer patients on chemotherapy. Use of statin decreases risk of pneumonia. Re-evaluating need for chronic PPI especially in high risk group patients can help to avoid overuse and possibly decreasing risk of pneumonia in this patient population.