Creatine supplementation does not impair kidney function in type 2 diabetic patients: a randomized, double-blind, placebo-controlled, clinical trial
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Creatine supplementation may have a therapeutic role in diabetes, but it is uncertain whether this supplement is safe for kidney function. The aim of this study was to investigate the effects of creatine supplementation on kidney function in type 2 diabetic patients. A randomized, double-blind, placebo-controlled trial was performed. The patients were randomly allocated to receive either creatine or placebo for 12 weeks. All the patients underwent exercise training throughout the trial. Subjects were assessed at baseline and after the intervention. Blood samples and 24-h urine samples were obtained for kidney function assessments. Additionally, 51Cr-EDTA clearance was performed. To ensure the compliance with creatine intake, we also assessed muscle phosphorylcreatine content. The creatine group presented higher muscle phosphorylcreatine content when compared to placebo group (CR Pre 44 ± 10, Post 70 ± 18 mmol/kg/wt; PL Pre 52 ± 13, Post 46 ± 13 mmol/kg/wt; p = 0.03; estimated difference between means 23.6; 95% confidence interval 1.42–45.8). No significant differences were observed for 51Cr-EDTA clearance (CR Pre 90.4 ± 16.9, Post 96.1 ± 15.0 mL/min/1.73 m2; PL Pre 97.9 ± 21.6, Post 96.4 ± 26.8 mL/min/1.73 m2; p = 0.58; estimated difference between means −0.3; 95% confidence interval −24.9 to 24.2). Creatinine clearance, serum and urinary urea, electrolytes, proteinuria, and albuminuria were unchanged. CR supplementation does not affect kidney function in type 2 diabetic patients, opening a window of opportunities to explore its promising therapeutic role in this population. ClinicalTrials.gov registration number: NCT00992043.
KeywordsPhosphorylcreatine Chronic kidney disease Diabetes Glomerular filtration rate
Bruno Gualano, Antonio Carlos Seguro and Guilherme G. Artioli received financial support from Conselho Nacional de Desenvolvimento Científico e Tecnológico. The authors declare that the present experiment complies with the current research ethics laws of the country it has been performed in. The experimental protocol has been approved by the institution’s Ethical Committee in Research and all the subjects have signed an informed consent.
Conflict of interest
The authors declare that they have no conflict of interest.
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