10.6084/m9.figshare.3501626.v1 Lemoine S. Lemoine S. Panaye M. Panaye M. Pelletier C. Pelletier C. Bon C. Bon C. Juillard L. Juillard L. Dubourg L. Dubourg L. Guebre-egziabher F. Guebre-egziabher F. PowerPoint Slides for: Cystatin C-Creatinine Based Glomerular Filtration Rate Equation in Obese Chronic Kidney Disease Patients: Impact of Deindexation and Gender Karger Publishers 2016 Glomerular filtration rate Cystatin C Creatinine Obesity Chronic Kidney Disease and Epidemiology 2016-07-26 08:27:36 Dataset https://karger.figshare.com/articles/dataset/PowerPoint_Slides_for_Cystatin_C-Creatinine_Based_Glomerular_Filtration_Rate_Equation_in_Obese_Chronic_Kidney_Disease_Patients_Impact_of_Deindexation_and_Gender/3501626 <i>Background:</i> Cystatin C is considered an alternative to creatinine to estimate glomerular filtration rate (GFR). However, studies have reported that increased adiposity is associated with a higher level of circulating cystatin C questioning the performance of estimation of GFR using cystatin C in obese subjects. <i>Methods:</i> We prospectively included 166 obese stages 1-5 chronic kidney disease (CKD) patients between 2013 and 2015. GFR was measured with a reference method without (measured GFR [mGFR]) and with adjustment to body surface area (mGFRr) and estimated (eGFR) or de-indexed eGFR using the Chronic Kidney Disease and Epidemiology (CKD-EPI) equation using creatinine (CKD-EPIcreat), cystatin (CKD-EPIcyst) and the combination of cystatin and creatinine (CKD-EPIcyst-creat). <i>Results:</i> The biases between mGFR and de-indexed CKD-EPIcyst-creat were significantly lower than de-indexed CKD-EPIcreat (p = 0.001). Accuracies were significantly better with de-indexed CKD-EPIcyst-creat compared to CKD-EPIcreat and CKD-EPIcyst, respectively (p = 0.04 and 0.03). Bland and Altman plot showed a great dispersion of all formulae when patients had a GFR >60 ml/min. Interestingly, there is a gender difference; biases, precisions and accuracies of de-indexed CKD-EPIcyst-creat were significantly lower in obese women. These results may be related to a difference in the change of body composition during obesity in men versus women and in fact only waist circumference (WC) was positively and significantly correlated with cystatin C (p < 0.0001) whereas body mass index (BMI; p = 0.3) was not; bias for CKD-EPIcyst-creat was related with WC. <i>Conclusion:</i> Cystatin C-creatinine-based GFR equations outperform creatinine-based formula in obese CKD patients especially those with BMI ≥35 and in obese women.