Creatine supplementation does not impair kidney function in type 2 diabetic patients: a randomized, double-blind, placebo-controlled, clinical trial
- 695 Downloads
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.
- Gualano B, Novaes RB, Artioli GG, Freire TO, Coelho DF, Scagliusi FB, Rogeri PS, Roschel H, Ugrinowitsch C, Lancha AH Jr (2008a) Effects of creatine supplementation on glucose tolerance and insulin sensitivity in sedentary healthy males undergoing aerobic training. Amino Acids 34(2):245–250. doi: 10.1007/s00726-007-0508-1 PubMedCrossRefGoogle Scholar
- Gualano B, Ugrinowitsch C, Novaes RB, Artioli GG, Shimizu MH, Seguro AC, Harris RC, Lancha AH Jr (2008b) Effects of creatine supplementation on renal function: A randomized, double-blind, placebo-controlled clinical trial. Eur J Appl Physiol 103(1):33–40. doi: 10.1007/s00421-007-0669-3 PubMedCrossRefGoogle Scholar
- Harris RC, Soderlund K, Hultman E (1992) Elevation of creatine in resting and exercised muscle of normal subjects by creatine supplementation. Clin Sci (Lond) 83(3):367–374Google Scholar
- Kuehl K, Goldberg L, Elliot D (1998) Renal insufficiency after creatine supplementation in a college football athlete (abstract). Med Sci Sports Exerc 30:S235Google Scholar
- Sewell DA, Harris RC (2002) Effect of creatine supplementation in the thoroughbred horse. Equine Vet J 18:239–242Google Scholar
- Taes YE, Delanghe JR, Wuyts B, van de Voorde J, Lameire NH (2003) Creatine supplementation does not affect kidney function in an animal model with pre-existing renal failure. Nephrol Dial Transplant 18:258–264Google Scholar
- Tarnopolsky MA, Bourgeois JM, Snow R, Keys S, Roy BD, Kwiecien JM, Turnbull J (2003) Histological assessment of intermediate and long-term creatine monohydrate supplementation in mice and rats. Am J Physiol Regul Integr Comp Physiol 285:R762–R769Google Scholar