Recurrent stone‐forming patients have high visceral fat ratio based on computed tomography images compared to first‐time stone‐forming patients

Objectives To compare various fat parameters based on computed tomography images between recurrent stone‐forming patients and patients forming stones for the first time. Methods Included in the present study were 300 patients with upper urinary tract calculi who had undergone active stone removal in our hospital. Using pretreatment computed tomography images, we measured visceral fat area and volume, subcutaneous fat area and volume, visceral fat area ratio and visceral fat volume ratio. We compared patient backgrounds and these fat parameters between those who recurrently formed stones and those who formed stones for the first time. We also performed logistic regression analysis to identify factors that contribute to severe stones. Results A total of 148 (49.3%) patients were recurrent stone‐forming patients. Recurrent stone‐forming patients were statistically significantly younger (P < 0.01) and there were more male patients (P < 0.01). In addition, visceral fat area ratio and visceral fat volume ratio in recurrent stone‐forming patients were significantly higher than those in first‐time stone‐forming patients (P = 0.03 and P = 0.01, respectively). On the other hand, there was no significant difference in visceral fat area (P = 0.32), subcutaneous fat area (P = 0.36), visceral fat volume (P = 0.38) or subcutaneous fat volume (P = 0.23). Receiver operating characteristics analysis showed that area under the curve of visceral fat volume ratio (0.583) for recurrent stones was larger than that of visceral fat area ratio (0.571). In multivariate analysis, increasing visceral fat volume ratio was an independent significant predictor of recurrent stones (P = 0.04). Conclusions Recurrent stone‐forming patients have high visceral fat ratios compared to first‐time stone‐forming patients, shown here for the first time.