Criteria for considering studies for this review.
Types of studies
We included randomized controlled clinical trials (RCTs). We made specific adaptations related to the research question if necessary.
To assess the efficacy of nonsteroidal mineralocorticoid receptor antagonists in type 2 diabetes patients with CKD, we included RCTs, as this study design, if performed appropriately, provides the best evidence for experimental therapies in highly controlled therapeutic settings.
We used the methods recommended in the Cochrane Handbook for Systematic Reviews of Interventions (9).
We included the following formats, if sufficient information was available on study design, characteristics of participants, interventions, and outcomes: full‐text publications.
We did not apply any limitation with respect to the length of follow‐up.
Types of participants
We included adults with a confirmed diagnosis of type 2 diabetes and chronic kidney disease (as described in the studies), and we did not exclude any studies based on sex, ethnicity, disease severity, or setting.
Types of interventions
We included the following interventions: any type or dose of nonsteroidal mineralocorticoid receptor antagonist (Finerenone).
We included the following comparisons: Finerenone versus standard care (plus placebo).
The cardiovascular outcomes were a composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure.
The renal outcomes were a composite of the first occurrence of kidney failure, a sustained decrease from baseline of at least 40% in the eGFR for a period of at least 4 weeks, or death from renal causes. Kidney failure was defined as end-stage kidney disease or as a sustained eGFR of less than 15 ml per minute per 1.73 m2 for a period of at least 4 weeks. End-stage kidney disease was defined as the initiation of chronic dialysis (for ≥90 days) or kidney transplantation.
For continuous outcomes, we recorded the mean, standard deviation (SD) and total number of participants in both the treatment and control groups. Where continuous outcomes used the same scale, we performed analyses using the mean difference (MD) with 95% confidence intervals (CIs). For continuous outcomes measured with different scales, we performed analyses using the standardized mean difference (SMD). For dichotomous outcomes, we recorded the number of events and total number of participants in both the treatment and control groups. We reported the pooled risk ratio (RR) with a 95% CI.
We assessed the heterogeneity of treatment effects between trials using a Chi² test with a significance level at P < 0.1. We used the I² statistic and visual examination to assess possible heterogeneity (I² statistic > 30% to signify moderate heterogeneity, I² statistic > 75% to signify considerable heterogeneity) (10). If the I² statistic was above 80%, we planned to explore potential causes through sensitivity and subgroup analyses. However, none of our analyses demonstrated an I² statistic > 80%.
Statistical analyses were performed using the Revman software package (Review Manager, Version 5.4. Copenhagen, The Nordic Cochrane Centre, the Cochrane Collaboration).