Current use, the drug use within 30 days before the index date; recent use, the drug use within 90 days, but not within 30 days, before the index date; past use, the drug use after the cohort entry, but not within 90 days before the index date.

*ORs of AKI for current/recent PPI users compared with past users were estimated using a conditional logistic regression model.

†Adjusted ORs were estimated by entering the potential confounders into the model.