New anthropometry-based age- and sex-specific reference values for urinary 24-hour creatinine excretion based on the adult Swiss population

• DOI: 10.1186/s12916-015-0275-x
• Publication Date: 2015-02-26T14:07:08Z
• Authors: Valentina Forni Ogna; Adam Ogna; Philippe Vuistiner; Menno Pruijm; Belen Ponte; Daniel Ackermann; Luca Gabutti; Nima Vakilzadeh; Markus Mohaupt; Pierre-Yves Martin; Idris Guessous; Antoinette Péchèr...; Fred Paccaud; Murielle Bochud; Michel Burnier
• Keywords: Adult; Male; 610 Medicine & health; Ethnic Groups; 2700 General Medicine; Urinalysis; Body Mass Index; 03 medical and health sciences; 0302 clinical medicine; Creatinine/urine; Reference Values; info:eu-repo/classification/ddc/616; Ethnicity; Humans; info:eu-repo/classification/ddc/613; ddc:613; Aged; ddc:616; Medicine(all); Anthropometry; Biomarkers/urine; Middle Aged; Urinalysis/standards; 3. Good health; Cross-Sectional Studies; Creatinine; Linear Models; Female; 10029 Clinic and Policlinic for Internal Medicine; Biomarkers; Switzerland; Research Article

Urinary creatinine excretion is used as a marker of completeness of timed urine collections, which are a keystone of several metabolic evaluations in clinical investigations and epidemiological surveys.We used data from two independent Swiss cross-sectional population-based studies with standardised 24-hour urinary collection and measured anthropometric variables. Only data from adults of European descent, with estimated glomerular filtration rate (eGFR) ≥60 ml/min/1.73 m2 and reported completeness of the urinary collection were retained. A linear regression model was developed to predict centiles of the 24-hour urinary creatinine excretion in 1,137 participants from the Swiss Survey on Salt and validated in 994 participants from the Swiss Kidney Project on Genes in Hypertension.The mean urinary creatinine excretion was 193 ± 41 μmol/kg/24 hours in men and 151 ± 38 μmol/kg/24 hours in women in the Swiss Survey on Salt. The values were inversely correlated with age and body mass index (BMI).We propose a validated prediction equation for 24-hour urinary creatinine excretion in the general European population, based on readily available variables such as age, sex and BMI, and a few derived normograms to ease its clinical application. This should help healthcare providers to interpret the completeness of a 24-hour urine collection in daily clinical practice and in epidemiological population studies.