Does Antioxidant Supplementation Slow Diabetic Kidney Disease Progression?

A study published in PLOS One found that the use of antioxidant agents may improve early kidney damage in patients with diabetic kidney disease (DKD). 

Since oxidative stress is known to worsen DKD, study authors sought to review available data on the possible benefits of chronic antioxidant supplementation on DKD progression. They conducted a systematic review and meta-analysis which included adult patients with DKD secondary to type 1 or type 2 diabetes mellitus.

Randomized controlled trials or quasi-randomized controlled trials evaluating any antioxidant supplementation such as vitamin A, vitamin C, vitamin E, selenium, zinc, methionine or ubiquinone alone or in combination were included in the analysis.

The primary outcome was progression to end-stage kidney disease; secondary outcomes included change in albuminuria, proteinuria, serum creatinine, and renal function. Fifteen studies involving 4,345 patients met the review criteria.  

The data showed antioxidants significantly reduced albuminuria vs. control (SMD –0.47, 95% CI: –0.78, –0.16) but had no effects on glomerular filtration rate (GFR) (MD –0.12mL/min/1.73m², 95% CI: –0.06, 0.01). “Evidence of benefits on the other outcomes of interest was inconclusive or lacking,” noted lead author Davide Bolignano.

The review was limited by the number of studies and small sample size. Studies in the future should include hard endpoints with longer follow-up and a larger sample size to confirm the benefits of antioxidant supplementation for delaying DKD progression.

For more information visit journals.plos.org.