Associations between visceral obesity and renal impairment in health checkup participants: a retrospective cohort study

Obesity-related renal dysfunction: gender-specific influence of visceral adiposity and early impact of metabolic and bariatric surgery

Introduction

Renal dysfunction is a recognized complication of obesity with an incompletely characterized pathophysiology. Improvement of glomerular filtration rate (GFR) after metabolic and bariatric surgery (MBS) has been reported across all classes of renal function. Inter-gender differences with regard to correlates of renal function have been described, but the influence of body composition is an understudied area. We aimed to explore determinants of renal function in obesity and to assess its variations after MBS, with a focus on body composition parameters in males and females, respectively.

Materials methods

We conducted a retrospective study on 196 patients who underwent laparoscopic sleeve gastrectomy, evaluated preoperatively and 6 months after the intervention. Recorded data included clinical and biochemical assessment, as well as body composition estimation via dual-energy X-ray absorptiometry. Serum creatinine-based formulas were used for the estimation of GFR.

Results

We included a total of 196 patients (80 males and 116 females), with a mean age of 41.43 ± 10.79. Median baseline body mass index was 42.6 (6.61) kg/m2 and 6 months excess weight loss (EWL) reached 71.43 ± 17.18%, in females, estimated GFR correlated negatively with visceral adipose tissue (VAT) mass (rho=-.368) and this correlation was stronger in females with type 2 diabetes mellitus. Moreover, women in the third VAT mass tertile were 5 times more likely to have reduced GFR compared to the first tertile. Renal function improved after MBS across all classes of filtration. In males, this improvement correlated with EWL (rho=.358) and lean mass variation (rho=-.412), while in females it correlated with VAT mass variation (rho=-.266).

Conclusions

Our results are consistent with previous findings on the positive impact of MBS on renal function and suggest a more prominent impact of visceral adiposity on GFR in females.

Central Body Fat Distribution and Kidney Function after Living Kidney Donation

BACKGROUND

In most screening guidelines, high body mass index (BMI) is considered a contraindication for kidney donation. New insights suggest that central body fat distribution might provide greater power in assessing kidney risk. This study aimed to determine whether BMI and central body fat distribution measures are associated with long-term kidney function after donor nephrectomy. We hypothesized that higher BMI, waist circumference (WC), and waist-to-height ratio (WHtR) were associated with lower kidney function long term after donation.

METHODS

The study population consisted of living kidney donors. BMI, WC, and WHtR were measured during donor screening. The outcome postdonation kidney function was assessed using measured GFR (mGFR) (mGFR, 125 I-iothalamate infusion) at 3 months ( n =1042), 5 years ( n =556), and 10 years ( n =210) of follow-up. Primary multivariable linear regression analyses were performed with BMI and WC and secondary analyses with WHtR. Linear mixed models were performed to investigate change in postdonation eGFR.

RESULTS

The donor age was 52±11 years, and 48% were male. The mean BMI was 26.1±3.6 kg/m 2 , and WC was 91±11 cm. Higher predonation BMI was associated with lower mGFR throughout follow-up: -1.35 (95% confidence interval [CI], -1.95 to -0.80), -1.55 (95% CI, -2.50 to -0.65), and -2.35 (95% CI, -4.10 to -0.60) ml/min per m 2 per 5 kg/m 2 higher BMI at 3 months, 5, and 10 years after donation, respectively, adjusted for sex, age, and predonation GFR. For WC, differences in mGFR were -1.30 (95% CI, -1.70 to -0.90), -1.50 (95% CI, -2.20 to -0.80), and -1.70 (95% CI, -3.00 to -0.50) ml/min per m 2 per 10 cm higher WC at 3 months, 5, and 10 years after donation, respectively. In male donors, BMI and WC were significantly associated with a negative postdonation change in eGFR.

CONCLUSIONS

Higher BMI and WC were independently associated with lower GFR (long term) after living kidney donation.

Effect of Weight Regain on Body Composition and Metabolic Biomarkers After Sleeve Gastrectomy: a Cross-Sectional Study from a Hospital Database

INTRODUCTION

Weight regain (WR) is described in approximately 30% of patient's post-bariatric surgery. It is related to the progression or recurrence of associated medical problems and decline in health-related quality of life. This study aimed to test the return of body composition and metabolic biomarkers to pre-operative levels when WR occurs.

METHODS

In this cross-sectional study conducted in 2021, patients were randomly selected from the hospital's electronic databases between 2001 and 2020. Patient demographic data, comorbidities, body compositions, and metabolic biomarkers were collected. Three groups were defined: groups A (WR), B (weight loss), and C (control group; patients with obesity who had not yet undergone bariatric surgery).

RESULTS

A total of 88 patients were enrolled in this study and matched with the control group. The body mass index in group A was 43.8 ± 6.9 kg/m²; group B was 28.6 ± 4.2; group C was 43.9 ± 7.1. Body muscle mass, body fat mass, and visceral fat significantly differed between groups A and B (p < 0.001) but not between groups A and C (p = 0.8). There was a significant difference in leptin, ghrelin, postprandial glucagon-like peptide-1, insulin, and fibroblast growth factor-21 (but not retinol-binding protein-4) between groups A and B. Most metabolic biomarkers in group A returned to the pre-operative values as in group C.

CONCLUSION

WR had a direct negative effect on body composition and metabolic biomarkers, whereby the values returned to pre-operative levels. Early detection of WR and possible additional therapy are necessary to prevent associated medical problems.

Lower Visceral Fat Area in Patients with Type 2 Diabetic Peripheral Neuropathy

OBJECTIVE

There is preliminary evidence that visceral fat area (VFA) was associated with the presence of type 2 diabetic peripheral neuropathy (DPN) in the Korean population; however, no studies have reported the association in Chinese population. The purpose of this study was to explore the possible correlation of VFA with DPN in such a population.

METHODS

A total of 2498 hospitalized patients with type 2 diabetes mellitus (T2DM) undergone VFA measurement, and were divided into DPN group (n=900) and non-DPN group (n=1594). The association of VFA with the presence of DPN was evaluated by correlation and multiple logistic regression analyses, generalized additive model with a smooth curve fitting, and receiver operating characteristic (ROC) curve analysis.

RESULTS

The VFA was significantly lower in the DPN group than in the non-DPN group (P < 0.001). VFA was significantly and positively associated with sural nerve conduction velocity (SNCV) and amplitude potential (SNAP) and negatively associated with the presence of DPN (all P< 0.001); there was no significant difference in the curve fitting (P = 0.344). Multivariate logistic regression analysis showed that the risk of presence of DPN decreased progressively across the VFA quartiles (P for trend < 0.001) and was significantly lower in patients in the highest VFA quartile than in those in the lowest quartile (OR: 0.382, 95% CI 0.151-0.968, P< 0.001) after multivariate adjustment. The ROC analysis revealed that the best cut-off value of VFA for predicting the presence of DPN was 50.5cm² (sensitivity 84.40%; specificity 34.00%).

CONCLUSION

These results suggest that lower VFA level may be associated with increased risk of the presence of DPN in T2DM patients.

Body Composition, Basal Metabolic Rate and Leptin in Long-Term Weight Regain After Roux-en-Y Gastric Bypass Are Similar to Pre-surgical Obesity

PURPOSE

The purpose of this study is to evaluate the relationship between body composition, basal metabolic rate (BMR), and serum concentrations of leptin with long-term weight regain after Roux-en-Y gastric bypass (RYGB) and compare it with obesity before surgery.

MATERIALS AND METHODS

Prospective longitudinal analytical study. Three groups were formed: individuals 60 months post RYGB, with weight regain (G1) and without it (G2), and individuals with obesity who had not undergone bariatric surgery (G3). Body fat (BF), body fat mass (BFM), visceral fat (VF), fat-free mass (FFM), skeletal muscle mass (SMM), and BMR were assessed by octapolar and multi-frequency electrical bioimpedance. Fasting serum concentrations of leptin were measured.

RESULTS

Seventy-two individuals were included, 24 in each group. Higher means of BF, BFM, VF, and leptin levels were observed in G1, when compared to G2 (BF: 47.5 ± 5.6 vs. 32.0 ± 8.0, p < 0.05; FBM: 47.8 ± 11.6 vs. 23.9 ± 7.0, p < 0.05; VF: 156.8 ± 30.2 vs. 96.1 ± 23.8, p < 0.05; leptin: 45,251.2 pg/mL ± 20,071.8 vs. 11,525.7 pg/mL ± 9177.5, p < 0.000). G1 and G2 did not differ in FFM, SMM, and BMR. G1 and G3 were similar according to BF, FFM, BMR, and leptin levels. Body composition, but not leptin, was correlated with %weight regain in G1 (FBM: r = 0.666, p < 0.000; BF: r = 0.428, p = 0.037; VF: r = 0.544, p = 0.006).

CONCLUSION

Long-term weight regain after RYGB is similar to pre-surgical obesity in body composition, BMR, and leptin concentrations, indicating relapse of metabolic and hormonal impairments associated with excessive body fat.

The risk of chronic kidney disease in relation to anthropometric measures of obesity: A Swedish cohort study

BACKGROUND

It has been shown that individuals with obesity have a higher risk for chronic kidney disease (CKD). However, it is unclear which measure of obesity is most useful for prediction of CKD in the general population. The aim of this large prospective study was to explore the association between several anthropometric measures of obesity, i. e., body mass index (BMI), waist circumference (WC), waist circumference to height ratio (WHtR), waist-to-hip ratio (WHR), percentage of body fat (BF%), weight, height and incidence of hospitalizations due to CKD, in a population-based cohort study.

METHODS

The 'Malmö Diet and Cancer Study (MDCS)' cohort in Sweden was examined during 1991 to 1996. A total of 28,449 subjects underwent measurement of anthropometric measures and blood pressure and filled out a questionnaire. Incidence of in- and outpatient hospital visits for CKD was monitored from the baseline examination over a mean follow-up of 18 years. Cox proportional hazards regression was used to explore the association between anthropometric measures and incidence of CKD, with adjustments for risk factors.

RESULTS

The final study population included 26,723 subjects, 45-73 years old at baseline. Higher values of BMI, WC, WHR, WHtR and weight were associated with an increased risk of developing CKD in both men and women. Only in women, higher values of BF% was associated with higher risk of CKD. Comparing the 4th vs 1st quartile of the obesity measure, the highest hazard ratio (HR) for CKD in men was observed for BMI, HR 1.51 (95% CI: 1.18-1.94) and weight (HR 1.52 (95% CI: 1.19-1.94). For women the highest HR for CKD was observed for BF%, HR 2.01 (95% CI: 1.45-2.78).

CONCLUSIONS

In this large prospective study, all anthropometric measures of obesity were associated with a substantially increased incidence of CKD, except for BF% in men. Some measures were slightly more predictive for the risk of CKD than others such as BMI and weight in men and BF% in women. In clinical daily practice use of all anthropometric measures of obesity might be equally useful to assess the risk of developing CKD. This study supports the strong evidence for an association between obesity and CKD.

Association of the ratio of visceral-to-subcutaneous fat volume with renal function among patients with primary aldosteronism

Patients with primary aldosteronism have a higher risk of chronic kidney disease. Visceral fat tissue is hypothesized to stimulate the adrenal glands to overproduce aldosterone, and aldosterone promotes visceral fat tissue to produce inflammatory cytokines. However, it is unclear whether the volume of accumulated visceral fat tissue is associated with renal impairment among patients with hyperaldosteronism. We conducted a single-center cross-sectional study to assess the association between the estimated glomerular filtration rate and the ratio of the visceral-to-subcutaneous fat volume calculated by computed tomography. One hundred eighty patients with primary aldosteronism were enrolled. The mean ± SD age was 52.7 ± 11.0 years, and 60.0% were women. The ratio of visceral-to-subcutaneous fat volume was highly correlated with the estimated glomerular filtration rate (r = 0.49, p < 0.001). In multiple linear regression models, the ratio of visceral-to-subcutaneous fat tissue volume was significantly associated with the estimated glomerular filtration rate (estimates: -4.56 mL/min/1.73 m² per 1-SD), and there was an interaction effect between the plasma aldosterone concentration and the ratio of visceral-to-subcutaneous fat volume (p < 0.05). The group with a higher plasma aldosterone concentration exhibited a steeper decline in eGFR than the lower plasma aldosterone concentration group when the ratio increased. The ratio of visceral-to-subcutaneous fat tissue volume was an independent risk factor for renal dysfunction. This association increased in the presence of a high plasma aldosterone concentration. Clinicians should pay attention to the ratio of visceral-to-subcutaneous fat tissue volume and encourage primary aldosteronism patients to improve their lifestyle in addition to treating renin-aldosterone activity.