SGLT2 inhibitors and kidney outcomes across the spectrum of kidney disease: a systematic review and meta-analysis.

Background: SGLT2 inhibitors have shown to reduce clinically meaningful kidney outcomes in individuals with chronic kidney disease at high risk for adverse outcomes. The effect of these agents in preventing clinically meaningful kidney outcomes in populations at lower risk remain uncertain. We aim to evaluate the effect of SGLT2 inhibitors on kidney outcomes across the Kidney Disease: Improving Global Outcomes (KDIGO) classification and urinary albumin-to-creatinine ratio (UACR) levels.

Methods: We have searched MEDLINE (PubMed), EMBASE and the Cochrane Central Register of Controlled Trials from inception up to August 8th, 2023. In pairs, researchers selected large (≥500 subjects per arm) randomized placebo-controlled trials of SGLT2 inhibitors, with a minimum duration of one year. Researchers independently extracted study-level data and assessed within-study risk of bias with the RoB 2.0 tool and quality of evidence with GRADE.

Results: We included 10 trials, encompassing 78,184 participants and a median follow-up of 2.7 years. Risk of bias was overall low. We performed meta-analyses summarizing individual study hazard ratios (HR) and 95% confidence intervals (CI) using a random-effects model. SGLT2 inhibitors reduced the composite kidney outcome across all KDIGO (HR [95% CI]: low 0.48 [0.32-0.71], moderate 0.60 [0.39-0.93], high 0.59 [0.47-0.74], very high 0.59 [0.49-0.72]) and UACR (HR [95% CI]: <30 mg/g 0.62 [0.50-0.78], ≥30 ≤300 mg/g 0.80 [0.67-0.96], >300 mg/g 0.61 [0.52-0.73]) groups, without evidence of heterogeneity between groups.

Limitations: Small proportion of subjects without diabetes in low-risk groups and lack of standardization of composite outcomes.

Conclusions: SGLT2 inhibitors consistently reduce kidney outcomes across the spectrum of KDIGO classes and UACR levels.