title: Evaluation of creatinine-based and cystatin C-based equations for estimation of glomerular filtration rate in type 1 diabetic patients.
abstract: Objective Several formulas based in different biomarkers may be used to estimate glomerular filtration rate (GRF). However, all of them have some limitations, and it is very important to evaluate their performances in different groups of patients. Therefore, we compared GFR, as estimated by creatinine-based and cystatin C-based equations, according to albuminuria, in type 1 diabetes (T1DM), in an observational case-control study. Subjects and methods T1DM patients were classified according to albuminuria: normoalbuminuric (n = 63), microalbuminuric (n = 30), macroalbuminuric (n = 32). GFR was calculated using creatinine-based and cystatin C-based (aMDRD, CKD-EPIcr, CKD-EPIcys, MacIsaac, Tan and CKD-EPIcrcys) equations. Spearman Correlation was used to evaluate the correlation of GFR estimated by the formulas with albuminuria. ROC curves were constructed to compare AUCs of GFR estimated by equations, in reference to macroalbuminuria. Sensibility, specificity and accuracy were calculated for a cut-off < 60 mL/min/1.73 m2. Results GFR estimated by creatinine-based and cystatin C-based equations significantly differed among normoalbuminuric, microalbuminuric and macroalbuminuric patients. Spearman correlation and AUCs of GFR estimated by creatinine-based and cystatin C-based formulas were very similar to each other, though cystatin C-based equations presented better correlation with albuminuria and higher AUCs than the creatinine-based ones, and the best accuracy to detect macroalbuminuric patients. Conclusion Although GFR estimated by all creatinine-based and cystatin C-based equations permitted the differentiation between T1DM patients, according to albuminuria, cystatin C-based equations presented best accuracy to detect macroalbuminuria in T1DM patients and should be considered in the clinical routine in order to increase the possibility of early diagnostic of chronic renal disease.
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Universidade Federal de São João Del Rei, Divinópolis, MG, Brasil.
authors.forename: Caroline Pereira
authors.initials: CP
authors.lastname: Domingueti
authors.affiliation: Departamento de Clínica Médica, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil.
authors.forename: Rodrigo Bastos
authors.initials: RB
authors.lastname: Fóscolo
authors.affiliation: Departamento de Pediatria, Faculdade de Medicina, UFMG, Belo Horizonte, MG, Brasil.
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Simões E Silva
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, UFMG, Belo Horizonte, MG, Brasil.
authors.forename: Luci Maria S
authors.initials: LM
authors.lastname: Dusse
authors.affiliation: Departamento de Endocrinologia e Metabolismo, Instituto de Educação e Pesquisa da Santa Casa de Belo Horizonte, Belo Horizonte, MG, Brasil.
authors.forename: Janice Sepúlveda
authors.initials: JS
authors.lastname: Reis
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, UFMG, Belo Horizonte, MG, Brasil.
authors.forename: Maria das Graças
authors.initials: Md
authors.lastname: Carvalho
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, UFMG, Belo Horizonte, MG, Brasil.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Fernandes
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, UFMG, Belo Horizonte, MG, Brasil.
authors.forename: Karina Braga
authors.initials: KB
authors.lastname: Gomes
mesh_terms: D000328:Adult; D000419:Albuminuria / Q000097:blood*; D000465:Algorithms; D015415:Biomarkers / Q000097:blood; D003404:Creatinine / Q000097:blood*; D055316:Cystatin C / Q000097:blood*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000097:blood / Q000175:diagnosis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012015:Reference Standards; D012016:Reference Values; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000175:diagnosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D055815:Young Adult
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D003404:Creatinine