Supplementary Material for: Long-Term Proton Pump Inhibitor Therapy Increases the Risk of Infection in Patients with Incident Hemodialysis

<b><i>Background:</i></b> Infection is one of the most common causes of death in patients with chronic kidney disease (CKD). Proton pump inhibitors (PPIs) are not only widely used in patients with CKD but also represent a known risk factor for infection in the general population. Here, we investigated associations between PPIs and infection events in patients with incident hemodialysis. <b><i>Methods:</i></b> We analyzed data from 485 consecutive patients with CKD who started hemodialysis at our hospital between January 2013 and December 2019. We analyzed associations between infection events and long-term (≥6 months) PPI use before and after propensity score-matched analysis. <b><i>Results:</i></b> Of the 485 patients, PPIs were administered to 177 patients (36.5%). During 24 months of follow-up, infection events occurred in 53 patients (29.9%) with PPIs and 40 patients (13.0%) without PPIs (<i>p</i> &lt; 0.001). Patients with PPIs had a significantly higher cumulative incidence rate of infection events than those without PPIs (hazard ratio [HR] 2.13, 95% confidence interval [CI]: 1.36–3.32; <i>p</i> &lt; 0.001). Even after propensity score-matched analysis (132 patients matched in each), the rate of infection events was higher for patients with PPIs (28.8% vs. 12.1%, HR 2.88, 95% CI: 1.61–5.16; <i>p</i> &lt; 0.001). Similar results were obtained for severe infection events in both unmatched (14.1% vs. 4.5%, HR 2.97, 95% CI: 1.47–6.00; <i>p</i> = 0.002) and propensity score-matched analyses (14.4% vs. 3.8%, HR 4.54, 95% CI: 1.85–11.13; <i>p</i> &lt; 0.001). <b><i>Conclusions:</i></b> In patients with incident hemodialysis, long-term PPI use increases the risk of infection. Clinicians should be wary of unnecessarily prolonging PPI therapy.