Changes in Muscle Quality and Body Composition 1 Year After Hand-Assisted Laparoscopic Donor Nephrectomy in Living Kidney Donors

OBJECTIVES Our aim was to investigate effects of surgery on living donors' body composition and clarify factors related to it. MATERIALS AND METHODS We evaluated preoperative computed tomography images of 335 living kidney donors (127 men, 209 women) to calculate 3 body composition parameters and changes with aging by sex: (1) skeletal muscle mass, quantified by skeletal muscle index; (2) fat distribution, calculated by visceral adipose tissue/subcutaneous adipose tissue ratio; and (3) muscle quality, quantified by intramuscular adipose tissue content. Thereafter, with pre- and postoperative computed tomography images from 75 living kidney donors (25 men, 50 women) after hand-assisted laparoscopic donor nephrectomy, we compared pre- and postoperative body composition changes. RESULTS Annual change in intramuscular adipose tissue content with age was 0.0049 in men and 0.0091 in women. Of 75 patients, 49 had lower quality of muscle, intramuscular adipose tissue content was significantly higher after nephrectomy (P < .001), and median change in intramuscular adipose tissue content was 0.061 (range, 0.018-0.11) in men and 0.052 (range, 0.017-0.18) in women. Univariate analysis revealed that skeletal mass index and visceral adipose tissue/subcutaneous adipose tissue ratio changes were significantly different between the intramuscular adipose tissue content improvement and deterioration groups. Multivariate analysis revealed skeletal mass index change was an independent factor for intramuscular adipose tissue content change (P = .0019). Intramuscular adipose tissue content change was negatively correlated with skeletal mass index change (r = -0.40). CONCLUSIONS Although muscle quality deteriorates after nephrectomy, maintaining muscle mass is important to retaining muscle quality.