SGLT2 inhibitors and renal outcomes in type 2 diabetes with or without renal impairment: A systematic review and meta-analysis

Background: Sodium–glucose co-transporter 2 (SGLT2) inhibitors may have renal protective effects in people with impaired kidney function. We assessed the use of SGLT2 inhibitors in people with type 2 diabetes with or without renal impairment [defined as estimated glomerular filtration rate (eGFR) of ≥30 and <60 ml/min/1.73 m² and/or UACR > 300 and ≤5000 mg/g] by conducting a systematic review and meta-analysis of available studies. Methods: Randomised controlled trials (RCTs) were identified from MEDLINE, EMABASE, Web of Science, the Cochrane Library, and search of bibliographies to March 2017. No relevant observational study was identified. Summary measures were presented as mean differences and narrative synthesis performed for studies that could not be pooled. Results: 42 articles which included 40 RCTs comprising 29,954 patients were included. In populations with renal impairment, SGLT2 inhibition compared with placebo was consistently associated with an initial decrease in eGFR followed by an increase and return to baseline levels. In pooled analysis of 17 studies in populations without renal impairment, there was no significant change in eGFR comparing SGLT2 inhibitors with placebo (mean difference, 0.51 ml/min/1.73 m²; 95% CI: −0.69, 1.72; p = 403). SGLT2 inhibition relative to placebo was associated with preservation in serum creatinine levels or initial increases followed by return to baseline levels in patients with renal impairment, but levels were preserved in patients without renal impairment. In populations with or without renal impairment, SGLT2 inhibitors (particularly canagliflozin and empagliflozin) compared with placebo were associated with decreased urine albumin, improved albuminiuria, slowed progression to macroalbuminuria, and reduced the risk of worsening renal impairment, the initiation of kidney transplant, and death from renal disease. Conclusions: Emerging data suggests that with SGLT2 inhibition, renal function seems to be preserved in people with diabetes with or without renal impairment. Furthermore, SGLT2 inhibition prevents further renal function deterioration and death from kidney disease in these patients.