Effect of statins on the treatment of early diabetic nephropathy: a systematic review and meta-analysis of nine randomized controlled trials

Diabetic nephropathy (DN) is a secondary disease of diabetes and could cause serious renal damage. This article aimed to investigate the effect of statins on the treatment of early DN.The databases were searched: Embase (January 2000-August 2021), PubMed (January 2000-August 2021), Cochrane [randomized controlled trial (RCT) database], Ovid (January 2000-August 2021), and clinicaltrials.gov (January 2000-August 2021) to obtain RCT literature related to statin intervention and DN. After screening, the risk of bias assessment was performed using the RevMan 5.4 software bias assessment tool, which was then used to perform the meta-analysis and obtain the therapeutic effects of statins by estimating indicators such as estimated glomerular filtration rate (eGFR), serum creatinine (SCR), total cholesterol (TC) level, total triglyceride (TG), and high-sensitivity C-reactive protein (hs-CRP).A total of 9 articles, 3,426 patients, and 5 types of statins were included. Meta-analysis showed that after treatment, eGFR in the experimental group was higher than in the control group [mean difference (MD) =5.80; 95% confidence interval (CI): (2.21, 9.40); P=0.002], SCR was lower than in the control group [MD =-0.46; 95% CI: (-0.69, -0.24); P<0.0001], hs-CRP level was lower than in the control group [MD =-1.20; 95% CI: (-2.05, -0.36); P=0.005], TC level was lower than in the control group [MD =-54.09; 95% CI: (-68.02, -40.16); P<0.00001], and TG level was lower than that in the control group [MD =-42.19; 95% CI: (-55.54, -28.84); P<0.00001].Statins can significantly increase eGFR, reduce SCR, decrease CRP level, and decrease blood lipid level in the treatment of DN, thus reducing the inflammatory response and protecting the kidney.