BACKGROUND: Although kidney size is commonly measured in patients with chronic kidney disease (CKD), its relationship with kidney function is poorly understood. We conducted this longitudinal study to better understand the relationship between kidney size and function. METHODS: We retrospectively studied 178 kidneys measured by ultrasound in 93 patients with CKD who did not have autosomal polycystic kidney disease. Renal function was measured using estimated glomerular filtration rate (GFR). A mixed model that accounted for repeated measurements or nested observations was used for statistical analysis. RESULTS: In cross-sectional analyses, the following independent variables emerged as predictors of kidney size: estimated GFR along with its squared term, height, age and interactions of each of these two independent variables with aetiology of CKD. In longitudinal analyses over a median follow-up of 3.7 years, after accounting for predictors of baseline kidney size such as aetiology, height and estimated GFR, we found that kidney atrophy occurred at a rate of 0.072 cm/year (SD 0.016, P = 0.007). This atrophy was 'blunted' with declining GFR. Each 1 mL/min/1.73 m(2)/year greater decline in eGFR abrogated kidney atrophy by 0.015 cm/year (P = 0.024). CONCLUSION: Although in cross-sectional surveys kidney size is directly related to function, the longitudinal relationship between form and function is inverted. Since the rate of change in GFR determines kidney atrophy, we conclude that kidney size is a determinant of renal prognosis.
BACKGROUND: Although kidney size is commonly measured in patients with chronic kidney disease (CKD), its relationship with kidney function is poorly understood. We conducted this longitudinal study to better understand the relationship between kidney size and function. METHODS: We retrospectively studied 178 kidneys measured by ultrasound in 93 patients with CKD who did not have autosomal polycystic kidney disease. Renal function was measured using estimated glomerular filtration rate (GFR). A mixed model that accounted for repeated measurements or nested observations was used for statistical analysis. RESULTS: In cross-sectional analyses, the following independent variables emerged as predictors of kidney size: estimated GFR along with its squared term, height, age and interactions of each of these two independent variables with aetiology of CKD. In longitudinal analyses over a median follow-up of 3.7 years, after accounting for predictors of baseline kidney size such as aetiology, height and estimated GFR, we found that kidney atrophy occurred at a rate of 0.072 cm/year (SD 0.016, P = 0.007). This atrophy was 'blunted' with declining GFR. Each 1 mL/min/1.73 m(2)/year greater decline in eGFR abrogated kidney atrophy by 0.015 cm/year (P = 0.024). CONCLUSION: Although in cross-sectional surveys kidney size is directly related to function, the longitudinal relationship between form and function is inverted. Since the rate of change in GFR determines kidney atrophy, we conclude that kidney size is a determinant of renal prognosis.
Authors: Gert Jan de Borst; Nicolette G C van der Sande; Frank L J Visseren; Yolanda van der Graaf; Hendrik M Nathoe; Tim Leiner; Peter J Blankestijn Journal: Clin J Am Soc Nephrol Date: 2017-05-09 Impact factor: 8.237
Authors: Samia Rafael Yamashita; Augusto Castelli von Atzingen; Wagner Iared; Alexandre Sérgio de Araújo Bezerra; Adriano Luiz Ammirati; Maria Eugênia Fernandes Canziani; Giuseppe D'Ippolito Journal: Radiol Bras Date: 2015 Jan-Feb
Authors: Luciano Selistre; Muriel Rabilloud; Pierre Cochat; Vandréa de Souza; Jean Iwaz; Sandrine Lemoine; Françoise Beyerle; Carlos E Poli-de-Figueiredo; Laurence Dubourg Journal: PLoS Med Date: 2016-03-29 Impact factor: 11.069