Reply to letter by dr L. Gao, on 'Lower Risk of Acute Kidney Injury in Hospitalized Patients Treated With SGLT-2 Inhibitors: A Retrospective Matched Cohort Study'.

We thank Gao and Lu for their thoughtful comments on our study investigating the association between sodium-glucose cotransporter-2 inhibitor (SGLT-2i) use and acute kidney injury (AKI) risk in hospitalised patients. In this reply, we clarify several methodological and interpretative aspects of our study. In particular, secondary analyses of continuation, discontinuation and initiation of SGLT-2i during hospitalisation should be interpreted cautiously, as these treatment decisions are likely influenced by clinical stability and other unmeasured factors. We further address concerns regarding AKI ascertainment, baseline creatinine selection, indication-stratified analyses, and the limited feasibility of dose- or agent-specific comparisons. Additional sensitivity analyses did not suggest major imbalance in early AKI detection between groups. Overall, we agree that the findings of our secondary analysis should be considered hypothesis-generating rather than definitive evidence for inpatient continuation of SGLT-2i. Future studies using prospective designs, time-updated exposure modelling or target trial emulation are needed to determine which patients may safely benefit from continuation during hospitalisation.