The Reduction of Visceral Adipose Tissue after Roux-en-Y Gastric Bypass Is more Pronounced in Patients with Impaired Glucose Metabolism

The effect of bariatric surgery type on cardiac reverse remodelling

INTRODUCTION

Bariatric surgery is effective in reversing adverse cardiac remodelling in obesity. However, it is unclear whether the three commonly performed operations; Roux-en-Y Gastric Bypass (RYGB), Laparoscopic Sleeve Gastrectomy (LSG) and Laparoscopic Adjustable Gastric Band (LAGB) are equal in their ability to reverse remodelling.

METHODS

Fifty-eight patients underwent CMR to assess left ventricular mass (LVM), LV mass:volume ratio (LVMVR) and LV eccentricity index (LVei) before and after bariatric surgery (26 RYGB, 22 LSG and 10 LAGB), including 46 with short-term (median 251-273 days) and 43 with longer-term (median 983-1027 days) follow-up. Abdominal visceral adipose tissue (VAT) and epicardial adipose tissue (EAT) were also assessed.

RESULTS

All three procedures resulted in significant decreases in excess body weight (48-70%). Percentage change in VAT and EAT was significantly greater following RYGB and LSG compared to LAGB at both timepoints (VAT:RYGB -47% and -57%, LSG -47% and -54%, LAGB -31% and -25%; EAT:RYGB -13% and -14%, LSG -16% and -19%, LAGB -5% and -5%). Patients undergoing LAGB, whilst having reduced LVM (-1% and -4%), had a smaller decrease at both short (RYGB: -8%, p < 0.005; LSG: -11%, p < 0.0001) and long (RYGB: -12%, p = 0.009; LSG: -13%, p < 0.0001) term timepoints. There was a significant decrease in LVMVR at the long-term timepoint following both RYGB (-7%, p = 0.006) and LSG (-7%, p = 0.021), but not LAGB (-2%, p = 0.912). LVei appeared to decrease at the long-term timepoint in those undergoing RYGB (-3%, p = 0.063) and LSG (-4%, p = 0.015), but not in those undergoing LAGB (1%, p = 0.857). In all patients, the change in LVM correlated with change in VAT (r = 0.338, p = 0.0134), while the change in LVei correlated with change in EAT (r = 0.437, p = 0.001).

CONCLUSIONS

RYGB and LSG appear to result in greater decreases in visceral adiposity, and greater reverse LV remodelling with larger reductions in LVM, concentric remodelling and pericardial restraint than LAGB.

Retrospective analysis of high-intensity focused electromagnetic procedure synchronized with radiofrequency energy for visceral fat reduction

BACKGROUND

Visceral adipose tissue (VAT), present in the abdominal cavity, oftentimes contributes to an unpleasant aesthetic appearance and can be correlated with serious health issues. High-intensity focused electromagnetic field (HIFEM) technology with synchronized radiofrequency (RF) was recently used for abdominal body shaping through subcutaneous fat reduction and muscle growth.

AIM

This study aimed to assess the effect of HIFEM + RF technology on VAT tissue.

METHODS

Data of 16 men and 24 women (22-62 years, 21.2-34.3 kg/cm2 ) from the original study were retrospectively reviewed. All subjects received three 30-min HIFEM + RF abdominal treatments once weekly for three consecutive weeks. The VAT area was measured in the axial plane of MRI scans at two levels: L4-L5 vertebrae and 5 cm above this level. The VAT was identified, segmented, and calculated, yielding total area in square centimeters per scan at both specified levels.

RESULTS

By thoughtful review of the subject's post-treatment MRI scans, no other changes in the abdominal cavity were found except for VAT. The evaluation showed a VAT reduction of 17.8% (p < 0.001) on average at 3-month follow-up, maintaining the results up to 6 months (-17.3%). Averaging the values obtained from both measured levels, the VAT, occupied an area of 100.2 ± 73.3 cm2 at the baseline. At the 3-month follow-up, the subjects achieved an average reduction of 17.9 cm2 , preserving the results at 6 months (-17.6 ± 17.3 cm).

CONCLUSION

This retrospective analysis of MRI images objectively documented the effect of HIFEM + RF abdominal therapy on VAT. The data indicates considerable VAT reduction without serious adverse events following the HIFEM + RF procedure.

Parameters of body composition and creeping fat are associated with activity of Crohn's disease

AIM

This study aimed at assessing body composition parameters, creeping fat (CrF), and Crohn's disease's (CD) activity based on the Magnetic Resonance Index of Activity (MaRIA).

METHODS

114 CD patients who underwent magnetic resonance enterography (MRE) between June 2010 and April 2020 were retrospectively assessed. The semi-automated body composition segmentation, the qualitative evaluation of CrF, and MaRIA were performed. Based on their MaRIA score, patients were divided into two groups: mild-to-moderate disease (MaRIA <11, n = 50) and severe disease (MaRIA ≥11, n = 64). MRE parameters were analyzed between both groups. Patients were dichotomized according to body composition categories and the presence of CrF. Univariate regression analyses were performed to investigate the association between dichotomized variables and severe disease. Significant variables were incorporated into the multivariate logistic regression model.

RESULTS

The severe disease group exhibited higher serum C-reactive protein (CRP) levels compared to the mild-to-moderate disease group (p ≤0.001). In the mild-to-moderate disease group, a higher proportion of patients had a body mass index (BMI) ≥ 25 (kg/m²) (32.0%) compared to the severe disease group (16.5%) (p = 0.04). The subcutaneous adipose tissue index (SATI) was significantly higher in the mild-to-moderate disease group (p = 0.04). The visceral to subcutaneous adipose tissue (VAT/SAT) ratio tended to be higher in the severe disease group (p = 0.09). There was no significant difference between both groups regarding total adipose tissue index (TATI) (p = 0.10), visceral adipose tissue index (VATI) (p = 0.51), intramuscular adipose tissue index (IMATI) (p = 0.38), skeletal muscle index (SMI) (p = 0.83), and sarcopenia (p = 0.75). In the multivariate analysis, CrF was significantly associated with severe disease (odds ratio [OR] 11.50, 95% confidence interval [CI] 3.13-42.17; p ≤0.001). Additionally, a BMI ≥ 25 (kg/m²) was protective against severe disease (OR: 0.34, 95% CI 0.12-0.95; p = 0.04).

CONCLUSION

CrF is significantly associated with CD activity.

Temporal Relationship Between Insulin Resistance and Lipid Accumulation After Bariatric Surgery: a Multicenter Cohort Study

PURPOSE

Insulin resistance (IR) is closely associated with lipid accumulation. Here, we investigated the temporal relationship between the two conditions after bariatric surgery.

MATERIALS AND METHODS

In total, 409 participants were enrolled from three bariatric centers in China from 2009 to 2018. We evaluated whether baseline IR (proxied by homeostasis model assessment of insulin resistance (HOMA-IR)) and lipid accumulation (proxied by visceral adiposity index (VAI) and lipid accumulation product (LAP)) were associated with follow-up IR and lipid accumulation (3 months postoperatively) using linear regression models. We then conducted a cross-lagged panel analysis model to simultaneously examine the bidirectional relationship between IR and lipid accumulation.

RESULTS

Multivariable linear regression analyses showed that baseline HOMA-IR was associated with follow-up VAI (β = 0.430, 95% CI: 0.082-0.778, p = 0.016) and LAP (β = 0.070, 95% CI: 0.010-0.130, p = 0.022). There was no relationship between baseline lipid accumulation and follow-up IR. Further cross-lagged panel analyses indicated that the path coefficient from baseline HOMA-IR to follow-up VAI (β₂ = 0.145, p = 0.003) was significantly greater than the coefficient from baseline VAI to follow-up HOMA-IR (β₁ =  - 0.013, p = 0.777). Similarly, the path coefficient from baseline HOMA-IR to follow-up LAP (β₂ = 0.141, p = 0.003) was significantly greater than the coefficient from baseline LAP to follow-up HOMA-IR (β₁ = 0.041, p = 0.391).

CONCLUSION

Our study demonstrated a unidirectional relationship from HOMA-IR to VAI and LAP, suggesting that the change in IR may precede lipid accumulation after surgery.

Changes in Lean Tissue Mass, Fat Mass, Biological Parameters and Resting Energy Expenditure over 24 Months Following Sleeve Gastrectomy

Sleeve gastrectomy (SG) induces weight loss but its effects on body composition (BC) are less well known. The aims of this longitudinal study were to analyse the BC changes from the acute phase up to weight stabilization following SG. Variations in the biological parameters related to glucose, lipids, inflammation, and resting energy expenditure (REE) were concomitantly analysed. Fat mass (FM), lean tissue mass (LTM), and visceral adipose tissue (VAT) were determined by dual-energy X-ray absorptiometry in 83 obese patients (75.9% women) before SG and 1, 12 and 24 months later. After 1 month, LTM and FM losses were comparable, whereas at 12 months the loss of FM exceeded that of LTM. Over this period, VAT also decreased significantly, biological parameters became normalized, and REE was reduced. For most of the BC, biological and metabolic parameters, no substantial variation was demonstrated beyond 12 months. In summary, SG induced a modification in BC changes during the first 12 months following SG. Although the significant LTM loss was not associated with an increase in sarcopenia prevalence, the preservation of LTM might have limited the reduction in REE, which is a longer-term weight-regain criterion.

Marked weight loss on liraglutide 3.0 mg: Real-life experience of a Swiss cohort with obesity

OBJECTIVE

This study investigated the effectiveness of liraglutide 3.0 mg daily in combination with a standardized multidisciplinary intervention on body weight and body composition changes in a real-life setting.

METHODS

A prospective, observational cohort study design was used. Adult patients with BMI > 35 kg/m² , or BMI > 28 kg/m² with greater than or equal to one metabolic comorbidity, were included (n = 54, 65% women). Liraglutide treatment was covered by Swiss health insurance. Clinical and biological data were collected at baseline, 4 months, and 10 months. Body composition was assessed by dual-energy x-ray absorptiometry at baseline and 10 months.

RESULTS

At 10 months, mean (SD) percentage weight loss (WL%) was -12.4% (5.5%) or -14.1 (6.6) kg. WL% was ≥5% in 87% of patients at 4 months and in 96% at 10 months. WL% was higher in women (-9.5% [3.1%] vs. men -7.2% [2.5%], p = 0.02) at 4 months and persisted at 10 months (-13.7% [5.2%] vs. -9.6% [5.1%], p = 0.006). WL% was associated with baseline percentage fat mass but not with age or BMI. Body composition showed a decrease in fat mass, visceral adipose tissue, and absolute lean mass.

CONCLUSIONS

In a real-world setting, liraglutide 3.0 mg led to beneficial changes in WL and body composition, with a greater impact in women.

Validity of dual-energy x-ray absorptiometry for estimation of visceral adipose tissue and visceral adipose tissue change after surgery-induced weight loss in women with severe obesity

OBJECTIVE

Reliable and simple methods to quantify visceral adipose tissue (VAT) and VAT changes are needed. This study investigated the validity of dual-energy x-ray absorptiometry (DXA) compared with magnetic resonance imaging (MRI) for estimating VAT cross sectionally and longitudinally after surgery-induced weight loss in women with severe obesity.

METHODS

Women with obesity (n = 36; mean age 43 [SD 10] years; 89% White) with DXA and MRI before bariatric surgery (T0) at 12 (T12) and 24 months (T24) post surgery were included. CoreScan (GE Healthcare, Chicago, Illinois) estimated VAT from 20% of the distance between the top of the iliac crest and the base of the skull. MRI VAT (total VAT) was measured from the base of the heart to the sacrum/coccyx on a whole-body scan.

RESULTS

Mean DXA VAT was 45% of MRI VAT at T0, 46% at T12, and 68% at T24. DXA underestimated change in MRI VAT between T0 and T12 by 26.1% (0.81 kg, p = 0.03) and by 71.7% (0.43 kg, p < 0.001) between T12 and T24. The relationship between DXA VAT and MRI VAT differed between T12 and T24 (p value for interaction = 0.03).

CONCLUSIONS

CoreScan lacks validity for comparing VAT across individuals or for estimating the size of changes within individuals; however, within the limits of measurement error, it may provide a useful indicator of whether some VAT change has occurred within an individual.

Effects of Roux-en-Y Gastric Bypass Versus Sleeve Gastrectomy on Body Composition for Patients with a BMI > 35 kg/m2 at 1 Year After Surgery

PURPOSE

Effects of Roux-en-Y gastric bypass (RYGB) versus sleeve gastrectomy (SG) on body composition have not been well compared. This meta-analysis aimed to compare changes in fat mass (FM) and lean tissue mass (LTM) for patients with a BMI > 35 kg/m² at 1 year after RYGB and SG.

METHODS

PubMed, EMBASE, the Cochrane Library, and ClinicalTrials.gov were searched ending in December 2021 for eligible studies which reported baseline and postsurgical BMI, FM, and LTM.

RESULTS

Of 17 eligible studies, 831 patients were included, 484 following RYGB and 347 following SG. Weighted mean differences (WMD) and 95% confidence intervals (CI) were from a random-effects model. For patients with a BMI > 35 kg/m², RYGB resulted in a more substantial reduction of BMI (- 14.13 kg/m² [95%CI - 14.74, - 13.53] versus - 11.96 kg/m² [95%CI - 12.81, - 11.11], P < 0.001) and FM (- 26.22 kg [95%CI - 28.31, - 24.12] versus - 21.50 kg [95%CI - 25.52, - 17.48], P = 0.042) than SG, and a relatively weaker impact on LTM (- 8.28 kg [95%CI - 9.33, - 7.22] versus - 10.12 kg [95%CI - 11.55, - 8.68], P = 0.043).

CONCLUSION

This meta-analysis study indicates that RYGB is superior to SG in reducing excess FM for patients with a BMI > 35 kg/m² and seems to be more beneficial when LTM preservation is taken into consideration.

Long-term body composition improvement in post-menopausal women following bariatric surgery: a cross-sectional and case-control study

OBJECTIVE

Bariatric surgery (BS) induces loss of body fat mass (FM) with an inexorable loss of lean mass (LM). Menopause leads to deleterious changes in body composition (BC) related to estrogen deficiency including LM loss and increase in total and visceral adipose tissue (VAT). This study aims to describe the long-term weight evolution of post-menopausal women after Roux-en-Y gastric bypass (RYGB) and to compare the BC between BS patients vs post-menopausal non-operated women.

DESIGN

Cross-sectional study of 60 post-menopausal women who underwent RYGB ≥2 years prior to the study with nested case-control design.

METHODS

Post-menopausal BS women were matched for age and BMI with controls. Both groups underwent DXA scan, lipids and glucose metabolism markers assessment.

RESULTS

Median follow-up was 7.5 (2-18) years. Percentage of total weight loss (TWL%) was 28.5 ± 10%. After RYGB, LM percentage of body weight (LM%) was positively associated with TWL% and negatively associated with nadir weight. Forty-one post-BS women were age- and BMI-matched with controls. Post-BS patients showed higher LM% (57.7% (±8%) vs 52.5% (±5%), P = 0.001), reduced FM% (39.4% (±8.4%) vs 45.9% (±5.4%), P < 0.01) and lower VAT (750.6 g (±496) vs 1295.3 g (±688), P < 0.01) with no difference in absolute LM compared to controls. While post-BS women showed a better lipid profile compared to controls, no difference was found in glucose markers.

CONCLUSIONS

Post-menopausal women after RYGB have a lower FM and VAT, preserved LM and a better lipid profile compared to controls. Weight loss after RYGB seems to have a persistent positive impact on metabolic health.

The magnitude and progress of lean body mass, fat-free mass, and skeletal muscle mass loss following bariatric surgery: A systematic review and meta-analysis

Postbariatric loss of muscle tissue could negatively affect long-term health due to its role in various bodily processes, such as metabolism and functional capacity. This meta-analysis aimed to unravel time-dependent changes in the magnitude and progress of lean body mass (LBM), fat-free mass (FFM), and skeletal muscle mass (SMM) loss following bariatric surgery. A systematic literature search was conducted in Pubmed, Embase, and Web of Science. Fifty-nine studies assessed LBM (n = 37), FFM (n = 20), or SMM (n = 3) preoperatively and ≥1 time points postsurgery. Random-effects meta-analyses were performed to determine pooled loss per outcome parameter and follow-up time point. At 12-month postsurgery, pooled LBM loss was -8.13 kg [95%CI -9.01; -7.26]. FFM loss and SMM loss were -8.23 kg [95%CI -10.74; -5.73] and -3.18 kg [95%CI -5.64; -0.71], respectively. About 55% of 12-month LBM loss occurred within 3-month postsurgery, followed by a more gradual decrease up to 12 months. Similar patterns were seen for FFM and SMM. In conclusion, >8 kg of LBM and FFM loss was observed within 1-year postsurgery. LBM, FFM, and SMM were predominantly lost within 3-month postsurgery, highlighting that interventions to mitigate such losses should be implemented perioperatively.

Impact of Bariatric Surgery on Adipose Tissue Biology

Bariatric surgery (BS) procedures are actually the most effective intervention to help subjects with severe obesity achieve significant and sustained weight loss. White adipose tissue (WAT) is increasingly recognized as the largest endocrine organ. Unhealthy WAT expansion through adipocyte hypertrophy has pleiotropic effects on adipocyte function and promotes obesity-associated metabolic complications. WAT dysfunction in obesity encompasses an altered adipokine secretome, unresolved inflammation, dysregulated autophagy, inappropriate extracellular matrix remodeling and insufficient angiogenic potential. In the last 10 years, accumulating evidence suggests that BS can improve the WAT function beyond reducing the fat depot sizes. The causal relationships between improved WAT function and the health benefits of BS merits further investigation. This review summarizes the current knowledge on the short-, medium- and long-term outcomes of BS on the WAT composition and function.

Improvement of glucose metabolism following rapid weight loss after bariatric surgery and its impact on reduction of visceral abdominal fat versus free fat muscle

BACKGROUND

Body fat distribution is highly associated with metabolic disturbances. Skeletal muscle plays an important role in glucose metabolism, as it serves as an important organ for glucose storage in the form of glycogen. In fact, low muscle mass has been associated with metabolic syndrome, type 2 diabetes (T2D), systemic inflammation, and decreased survival.

OBJECTIVES

To compare the relationship between visceral abdominal fat (VAF) and fat free mass (FFM) with the improved glucose metabolism after bariatric surgery.

SETTING

University hospital, United States.

METHODS

A retrospective review was performed of all patients who underwent bariatric surgery between 2011 and 2017 at a university hospital in the United States. In severely obese patients with T2D, we measured the VAF via abdominal computed tomography scan and we calculated the FFM preoperatively and at a 12-month follow-up. Data collected included baseline demographic characteristics and perioperative parameters, such as treatment for hypertension (HTN) and T2D, body mass index (BMI), glycated hemoglobin (HbA1C), glucose, and lipid profile.

RESULTS

A total of 25 patients met the inclusion criteria. The average age was 52.5 ± 11.6 years. The initial BMI was 41.41 ± 5.7 kg/m² and the postoperative BMI was 31.7 ± 6.9 kg/m² (P < .0001). The preoperative VAF volume was 184.6 ± 90.2 cm³ and the postoperative VAF volume was 93.8 ± 46.8 cm³ at the 12-month follow-up (P < .0001). The preoperative FFM was 55.2 ± 11.4 kg and the postoperative FFM was 49.1 ± 12 kg (P < .072). The preoperative HbA1C was 5.8% ± .9%, which decreased postoperatively to 5.3% ± .4% at the 12-month follow-up (P < .013).

CONCLUSION

Bariatric surgery has been demonstrated to be an effective treatment modality for severe obesity and T2D. Our results suggest that at 12 months, there is a reduction in VAF and HbA1C without a significant loss of FFM. Further prospective studies are needed to better understand these findings.

Weight Loss Directly Influences Intermediate-Term Remission of Diabetes Mellitus After Bariatric Surgery: A Retrospective Case-Control Study

PURPOSE

Roux en Y gastric bypass surgery (RYGB) is an effective therapy for patients with severe obesity. It induces both significant weight loss and rapid improvements of metabolic complications. This study was undertaken to better define the direct role of weight loss in the metabolic improvements.

METHODS

A retrospective, case-control study of a cohort of 649 patients with obesity who underwent RYGB, comparing higher and lower responders at 2 years after surgery (n = 100 pairs). Pairs of patients were matched for age, gender, and initial BMI. The rates of remission of diabetes, hypertension, dyslipidemia, and hyperuricemia were compared using a mixed effects logistic regression analysis.

RESULTS

Diabetes before surgery was present in 12/100 lower responders and 17/100 higher responders. Remission at 2 years was observed in 4/12 (33%) of lower responders, compared to 15/17 (88%) of higher responders. Thus, the odds of diabetes remission was significantly smaller in lower responders (OR = 0.067, 95% CI 0.01-0.447). A mixed model regression analysis of all the parameters for each patient showed that the odds of achieving remission of any comorbidity was significantly lower in lower responders (OR = 0.62, 95% CI = 0.39-0.97).

CONCLUSION

We could demonstrate that weight loss is a significant determinant of the remission of diabetes 2 years after RYGB. These data underline the importance of weight loss in the benefits of this procedure.

Obesity and Weight Gain in Persons with HIV

PURPOSE OF REVIEW

The proportion of overweight and obese persons with HIV (PWH) has increased since the introduction of antiretroviral therapy (ART). We aim to summarize recent literature on risks of weight gain, discuss adipose tissue changes in HIV and obesity, and synthesize current understanding of how excess adiposity and HIV contribute to metabolic complications.

RECENT FINDINGS

Recent studies have implicated contemporary ART regimens, including use of integrase strand transfer inhibitors and tenofovir alafenamide, as a contributor to weight gain, though the mechanisms are unclear. Metabolic dysregulation is linked to ectopic fat and alterations in adipose immune cell populations that accompany HIV and obesity. These factors contribute to an increasing burden of metabolic diseases in the aging HIV population. Obesity compounds an increasing burden of metabolic disease among PWH, and understanding the role of fat partitioning and HIV- and ART-related adipose tissue dysfunction may guide prevention and treatment strategies.

Acute and longer-term body composition changes after bariatric surgery

BACKGROUND

Bariatric surgery induces weight loss but its acute and longer-term effects on body composition (BC) are largely unknown.

OBJECTIVES

To determine the BC changes in obese French patients after sleeve gastrectomy (SG) at 1 and 12 months.

SETTING

Obesity Reference Center, University Hospital of Montpellier, France.

METHODS

Whole and localized BC (lean tissue mass [LTM] and fat mass [FM]) and abdominal adiposity, including total adipose tissue, visceral adipose tissue, and subcutaneous adipose tissue, were determined by dual-energy X-ray absorptiometry in 30 obese patients (25 women, 83.3%) just before SG and 1 and 12 months later.

RESULTS

The mean weight loss was -9.7 ± 2.6 kg at 1 month and -32.1 ± 10.3 kg at 12 months. This weight loss was due to an equivalent decrease in LTM and FM in the acute phase, while FM loss appeared to be the main cause in the chronic phase. For each component (LTM and FM), the loss was relatively homogeneous across sites. Compared with the presurgical values, android and gynoid tissue and total adipose tissue, visceral adipose tissue, and subcutaneous adipose tissue changed significantly over the 12-month period. No basal clinical parameter was predictive of the variation in LTM, whereas age and the whole-body LTM/FM ratio were associated with the decrease in FM.

CONCLUSION

This study demonstrates that SG induces a clear modification in BC, characterized by a decrease in LTM in the acute phase and sustained FM loss in the first year. These results suggest that the early phase should be targeted for strategies to reduce LTM loss, which is a longer-term weight-regain criterion. Further studies to investigate the potential advantages of visceral adipose tissue compared with whole-body FM for improving post-SG co-morbidities should be performed.