Visceral obesity in Asian living kidney donors significantly impacts early renal function after donor nephrectomy

Abdominal adipose tissue and type 2 diabetic kidney disease: adipose radiology assessment, impact, and mechanisms

Diabetic kidney disease (DKD) is a significant healthcare burden worldwide that substantially increases the risk of kidney failure and cardiovascular events. To reduce the prevalence of DKD, extensive research is being conducted to determine the risk factors and consequently implement early interventions. Patients with type 2 diabetes mellitus (T2DM) are more likely to be obese. Abdominal adiposity is associated with a greater risk of kidney damage than general obesity. Abdominal adipose tissue can be divided into different fat depots according to the location and function, including visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), perirenal adipose tissue (PAT), and renal sinus adipose tissue (RSAT), which can be accurately measured by radiology techniques, such as computed tomography (CT) and magnetic resonance imaging (MRI). Abdominal fat depots may affect the development of DKD through different mechanisms, and radiologic abdominal adipose characteristics may serve as imaging indicators of DKD risk. This review will first describe the CT/MRI-based assessment of abdominal adipose depots and subsequently describe the current studies on abdominal adipose tissue and DKD development, as well as the underlying mechanisms in patients of T2DM with DKD.

Effects of body fat components on early renal functions of individuals following kidney donation

Objective:

Obesity stands as a risk factor for the chronic kidney disease. The objective of this study was to investigate the relationship between early renal function following kidney donation and the measurements of body fat components.

Methods:

In total, 86 donors followed up for at least 6 months postoperatively were included. Height and weight measurements and results of laboratory analysis of all donors were recorded retrospectively. Visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), hepatic fat (HF), pancreatic fat (PF) and splenic fat (SF) measurements were performed, and pancreatic splenic fat fraction difference (P−S) and pancreatic splenic fat fraction ratio (P/S) were calculated by a radiologist using the records of preoperative computed tomography scans of donors.

Results:

The estimated glomerular filtration rate (eGFR), serum creatinine and spot urinary microalbumin/creatinine ratio values of the donors at the sixth month postoperatively were statistically different from those of the preoperative values ( p < 0.001). In addition, the individuals were divided into two categories based on the postoperative eGFR: ⩾ 60 mL/min/1.73 m2 and < 60 mL/min/1.73 m2. Age, low-density lipoprotein (LDL) level and VAT/SAT ratio were lower in group eGFR: ⩾ 60 ( p < 0.001, p = 0.03, p = 0.007, respectively). Age and VAT/SAT ratio were the parameters found to be affecting the eGFR significantly, and VAT/SAT ratio (0.729, 95% CI: 0.602–0.856, p = 0.007) had higher predictive value in receiver operating characteristic curve (ROC).

Conclusion:

Preoperative measurements of body fat components may provide significant information to predict postoperative renal functions of kidney donor candidates.

Level of evidence:

Not applicable.

Pre-transplant morphometry by computed tomography scan and post-transplant dialysis risk in overweight or obese kidney transplant recipients

PURPOSE

Adipose distribution and sarcopenia could better assess kidney transplantation outcomes than body mass index (BMI) and have been poorly evaluated among obese and overweight recipients. We aimed to evaluate morphometric radiologic markers to predict post-operative dialysis within this population.

METHODS

We conducted a retrospective study including patients with a BMI > 25 kg/m² undergoing kidney transplantation during 5 years. Subcutaneous adipose tissue surface (SAT), visceral adipose tissue surface (VAT), and psoas surface were measured on CT scans sections. A model predictive of post-transplantation dialysis was elaborated through a multivariable logistic regression and was compared to a model including only BMI.

RESULTS

Overall, 248 patients were included whom mean (SD) BMI and age were, respectively, 29.7 kg/m2 (3.6) and 56 years (12.7). Of them, 83 (33.5%) needed dialysis: 14 (5.7%) for primary kidney failure and 69 (27.8%) for delayed kidney function. On multivariable analysis, SAT, VAT and deceased donor were significantly associated with post-operative dialysis (respectively, OR [95%CI]:1.6 [1.1-2.6], 1.6[1.1-2.6], and 7.5 [1.6-56]). The area under the curve of this predictive model was 0.70 versus 0.64 for a BMI-based model.

CONCLUSION

High VAT and SAT were associated with post-transplantation dialysis. A predictive model based on these morphometrics could provide a better appreciation of graft recovery after transplantation among obese and overweight recipients. External validation is needed.