Relationship among total kidney volume, renal function and age

Purpose: We measured kidney volume using software and investigated the relationship between kidney volume and renal function.

Materials and methods: Age, gender, height, body weight, body mass index, body surface area and serum creatinine were recorded for 539 normal individuals. A tissue segmentation tool program was used to measure kidney volume from computerized tomography images. The glomerular filtration rate was calculated using the Cockcroft-Gault equation and an abbreviated modification of diet in renal disease equation. We looked for correlations of renal parenchymal volume with age and anthropometric measurements. We also tested for a correlation between kidney volume and renal function using the glomerular filtration rate according to the Cockcroft-Gault and modification of diet in renal disease equations.

Results: Mean kidney volume in all participants was 261.3 ± 58.1 ml. Mean volume in men was approximately 14 ml greater than in women (266.1 vs 251.8 ml, p = 0.004). Kidney volume correlated significantly with height (r = 0.344, p <0.001), body weight (r = 0.343, p <0.001), body mass index (r = 0.177, p <0.001), body surface area (r = 0.371, p <0.001) and age (r = -0.418, p <0.001). Kidney volume also correlated with the glomerular filtration rate according to the Cockcroft-Gault and modification of diet in renal disease equations (p <0.001, r = 0.615 and p <0.001, r = 0.432, respectively). Kidney volume and the glomerular filtration rate decreased in parallel with increasing age.

Conclusions: Kidney volume correlates well with renal function and anthropometric measurements. Knowledge of these relationships will be valuable in clinical urology and nephrology.