Effects of adding tripterygium glycosides to angiotensin-converting enzyme inhibitors or angiotensin receptor blockers on albuminuria in patients with diabetic nephropathy

Introduction: Tripterygium glycosides (TGs) have been widely used in China to treat diabetic nephropathy (DN); however, proof of their use is scarce. The present study aimed to evaluate the effectiveness and safety of adding TGs to angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs).

Methods: By searching Embase, MEDLINE, Cochrane Library, SINOMED, China National Knowledge Infrastructure, VIP Information/Chinese Scientific Journals, and WANFANG databases, we identified previous studies that met the specific selection criteria and included them in the meta-analysis. Analyses were performed using Review Manager (version 5.3).

Results: Nine randomized controlled trials were included in the final meta-analysis. Patients were compared before and after treatment with ACE inhibitors or ARBs plus TGs, or ACE inhibitors or ARBs alone. The results revealed that treatment with ACE inhibitors or ARBs plus TGs resulted in significantly greater reductions in 24-h urinary total protein (UTP) levels (trial duration <2 months, mean difference [MD]: -0.25; 95% confidence interval [CI]: -0.32, -0.18; trial duration between 2 and 6 months, MD: -0.39; 95% CI: -0.44, -0.33; trial duration >6 months, MD: -2.09; 95% CI: -2.89, -1.29) compared with treatment using ACE inhibitors or ARBs alone. Additionally, ACE inhibitors or ARBs plus TGs showed better results after long-term administration. Treatment with ACE inhibitors or ARBs plus TGs resulted in significantly greater reductions in serum creatinine (SCr) compared with ACE inhibitors or ARBs alone (MD: -9.87; 95% CI: -13.76, -5.97).

Conclusion: In patients with DN, adding TGs to ACE inhibitors or ARBs significantly lowered both the 24-h UTP and SCr levels. Therefore, ACE inhibitors or ARBs plus TGs might improve the treatment of DN in patients.