Changes in bone mass and body composition after bariatric surgery

Prospective Study to Evaluate Rectus Femoris Muscle Ultrasound for Body Composition Analysis in Patients Undergoing Bariatric Surgery

Background: Bariatric surgery (BS) has a significant impact on body composition (BC) and consequently may affect established sarcopenic obesity (SO) in candidate patients. The aim of this study was to assess the utility of muscle ultrasound (MUS) of rectus femoris thickness (RFT) for the evaluation of BC and skeletal muscle function in patients undergoing BS compared to bioimpedance analysis (BIA), dual-energy X-ray absorptiometry (DEXA) and dynamometry. On the other hand, we aimed to demonstrate how MUS of RFT correlates with quality of life (QoL) in this population, likely due to its ability to detect regional quadriceps muscle sarcopenia compared to the other mentioned methods. Methods: This was a prospective pilot study that included 77 participants (64.9% female, mean age: 53.2 ± 8.67 years) who underwent BS. Handgrip strength was measured using a dynamometer, fat-free mass index (iFFM) was assessed by BIA, appendicular muscle index (AMI) was calculated using DEXA, and RFT was measured by MUS. Moreover, homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. All these measurements were conducted 1 month prior to BS and at the 12-month follow-up. QoL was assessed using the Moorehead-Ardelt questionnaire. Results: The mean BMI decreased by 12.95 ± 3.56 kg/m2 (p = 0.001). Firstly, we observed a positive correlation pre-surgery between HOMA and RFT (r = 0.27, p = 0.02), iFFM (r = 0.36, p = 0.001), AMI (r = 0.31, p = 0.01) and dynamometer readings (r = 0.26, p = 0.02). In addition, we found a correlation between RFT and iFFM (pre-surgery: r = 0.31, p = 0.01; post-surgery: r = 0.25, p = 0.05) and between RFT and lower-extremity AMI post-surgery (r = 0.27, p = 0.04). Secondly, we observed significant reductions in iFFM, AMI and RFT (p = 0.001), but not in dynamometer readings (p = 0.94). Finally, a tendency to a positive correlation between QoL questionnaire and RFT post-surgery results (r = 0.23, p = 0.079) was observed. Conclusions: Our results suggest that RFT measured by MUS is useful for evaluating SO and for the follow-up of these patients after BS. Moreover, RFT can provide relevant information about regional sarcopenia and probably has an accurate correlation with QoL in comparison with the other methods.

Effect of Nutritional Deprivation after Sleeve Gastrectomy on Bone Mass, Periostin, Sclerostin and Semaphorin 4D: A Two-Year Longitudinal Study

Bariatric surgery induces bone loss, but the exact mechanisms by which this process occurs are not fully known. The aims of this 2-year longitudinal study were to (i) investigate the changes in areal bone mineral density (aBMD) and bone turnover markers following sleeve gastrectomy (SG) and (ii) determine the parameters associated with the aBMD variations. Bone turnover markers, sclerostin, periostin and semaphorin 4D were assessed before and 1, 12 and 24 months after SG, and aBMD was determined by DXA at baseline and after 12 and 24 months in 83 patients with obesity. Bone turnover increased from 1 month, peaked at 12 months and remained elevated at 24 months. Periostin and sclerostin presented only modest increases at 1 month, whereas semaphorin 4D showed increases only at 12 and 24 months. A significant aBMD decrease was observed only at total hip regions at 12 and 24 months. This demineralisation was mainly related to body weight loss. In summary, reduced aBMD was observed after SG in the hip region (mechanical-loading bone sites) due to an increase in bone turnover in favour of bone resorption. Periostin, sclerostin and semaphorin 4D levels varied after SG, showing different time lags, but contrary to weight loss, these biological parameters did not seem to be directly implicated in the skeletal deterioration.

Effect of regional body composition changes on bone density remodeling after sleeve gastrectomy

Background

Sleeve gastrectomy (SG) results in bone mineral density (BMD) loss and varying body composition parameters. However, the effects of body compositions on bone health are controversial. In order to accurately demonstrate their relationship and provide new insights into the causes of BMD loss after sleeve gastrectomy, this study is aimed to investigate the role of changes in body composition in BMD loss 12 months after SG.

Methods

41 Chinese individuals with obesity (25 women and 16 men) who underwent SG were prospectively examined for at least 12 months. Measurements of anthropometrics, body composition, BMD and blood samples were collected.

Results

For 12 months, the femoral neck (FN) BMD and total hip (TH) BMD decreased significantly compared with baseline in both sexes but not lumbar spine (LS) BMD. Greater TH BMD loss was observed in men than in women. For the first 6 months post-SG, the FN BMD loss was positively associated with the estimated fat free mass index (eFFMI) reduction in women (adjusted β = 0.77, P = 0.004) and positively associated with reduction of subcutaneous fat area (SFA) in men (r = 0.931, P = 0.007). For 12 months post-SG, the FN BMD loss was negatively associated with visceral fat area (VFA) reduction in women (adjusted β = -0.58, P = 0.027) and men (adjusted β = -0.68, P = 0.032). TH BMD loss was positively associated with waist circumference reduction in women (r = 0.448, P = 0.028).

Conclusion

FN and TH BMD decrease after SG in both women and men. The changes in body compositions are associated with BMD loss at different time points and bone sites. Our data emphasize the limitation of simply taking the total weight loss (% TWL) as an influencing factor of bone mineral density and the necessity of delineating body composition in relevant studies.

Effects of preoperative sarcopenia-related parameters on the musculoskeletal and metabolic outcomes after bariatric surgery: a one-year longitudinal study in females

Reduced muscle mass and/or strength are risk factors for metabolic and musculoskeletal impairment. The present study evaluated anthropometric, metabolic, and musculoskeletal outcomes in females with and without sarcopenic-obesity parameters who underwent bariatric surgery during a 1-year follow-up. A prospective, single-center cohort study was conducted in females with obesity undergoing preoperative evaluation for surgery. In the preoperative period, females were allocated into obesity with sarcopenic-obesity parameters (SOP group, n = 15) and without sarcopenic-obesity parameters (obesity group, n = 21). Sarcopenic obesity parameters were defined as lower appendicular skeletal mass adjusted for weight (ASM/wt) and/or low handgrip strength (HGS). Anthropometric, metabolic, and musculoskeletal parameters were assessed before surgery and at 3 months, 6 months, and a 1-year after bariatric surgery. Weight loss was similar between groups (p > 0.05). Weight, body mass index, fat mass, body fat percentage, skeletal muscle mass, fat-free mass, fat-free mass index, HGS were reduced in both groups during the 1-year follow-up (p < 0.05). However, when muscle mass and strength were analyzed relative to body size, an improvement after bariatric surgery was found in both groups (p < 0.05). Total cholesterol, LDL-c, triglycerides, fasting glucose, glycated hemoglobin, insulin, and insulin resistance were reduced in both groups during the 1-year follow-up (p < 0.05). In addition, HDL-c serum concentration increased in females with and without sarcopenic-obesity parameters over the 1-year follow-up (p < 0.05). Both groups had decreased bone mineral density (BMD) at all sites (lumbar spine, femoral neck, and total femur) over the 1-year follow-up (p < 0.05). The highest quartile of ASM/wt was positively associated with BMD variables in a longitudinal analysis, suggesting that preserved ASM/wt in pre-surgery may be beneficial for BMD after 1 year of bariatric surgery. The results showed that bariatric surgery promotes similar musculoskeletal and metabolic changes in females with preserved muscle mass and strength or in females with sarcopenia-related parameters.

Long-Term Changes in Bone Density and Bone Metabolism After Gastric Bypass Surgery: a Retrospective Cohort Study

PURPOSE

Patients with severe obesity submitted to Roux-en-Y gastric bypass (RYGB) are at risk of developing long-term hypovitaminosis D and secondary hyperparathyroidism (SHPT) as well as osteometabolic disease. This study aimed to evaluate calcium-vitamin D-PTH axis and bone mineral density (BMD) changes from post-RYGB patients who were followed-up until a median of 5 years.

MATERIALS AND METHODS

Vitamin D deficiency was defined as 25-hydroxyvitamin D <20 ng/mL and SHPT as PTH >68 pg/mL, in patients with normal serum creatinine and calcium. BMD was estimated by dual-energy X-ray absorptiometry (DXA, g/cm²).

RESULTS

We included 127 post-RYGB patients (51±10.6 years, 87.4% self-declared White, 91.3% female, 52.8% postmenopausal). Vitamin D deficiency prevalence was the highest (41.5%) in the second year and the lowest (21.2%) in the third year (p<0.05). SHPT prevalence was 65.4% in the second year and increased to 83.7% in the sixth year (p<0.05). Patients with low BMD in lumbar, femoral neck, and total proximal femur were older and presented menopausal status more frequently than normal BMD group (p<0.05). Older age was a risk marker for altered BMD in femoral neck (OR=1.185; 95% CI 1.118-1.256) and in total proximal femur (OR=1.158; 95% CI 1.066-1.258), both after adjusting for follow-up and excess weight loss.

CONCLUSION

After 5 years, most bariatric patients presented calcium-vitamin D-PTH axis disruption, in which SHPT was more frequent than hypovitaminosis D. Older patients and menopausal women presented higher rates of low BMD, and older age was a risk marker, especially for low BMD in femoral sites.

Lean mass and strength profile of women submitted to bariatric surgery: comparison of the EWGSOP2 and FNIH classification for sarcopenia - ASBS program phase II

Aim: To assess the effect of bariatric surgery on the lean mass of women after one year of the procedure, comparing its outcomes upon the classification from both the Foundation of the National Institutes of Health (FNIH) and the European Working Group on Sarcopenia in the Elderly People (EWGSOP). Material and methods: Twenty-eight obese women aged 40.5 ± 9.8 yrs who underwent Roux-en-Y gastric bypass (RYGB) were included. 27 of them were reassessed after 6 months of surgery, and 16 completed the one-year follow-up. Pre-sarcopenia condition was assessed through a handgrip strength test and body composition by dual-energy X-ray absorptiometry (DXA). Total body mass, body mass index, and lean mass (LM) were collected prior to, 6 and 12 months after RYGB surgery. Results: All subjects reassessed after 12 months were diagnosed with pre-sarcopenia according to the FNIH classification criteria, while according to the EWGSOP2 Consensus they presented normal values. LM represented 14% of the influence on handgrip strength (p = .049) after 6 months of surgery; however, its influence on strength after 12 months increased to 30% (p = .028). Conclusion: The FNIH classification is the most effective criteria since it uses LM content as the first test, considering that strength capacity needs more time to be affected by the surgical procedure. On the other hand, the EWGSOP2 classification should not be applied to determine the loss of LM in younger populations regardless of what may have caused such changes.

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.

Effects of anthropometric parameters on bone mineral density in women: from perimenopause to old age

AIM

To analyze the influence of body components on bone mineral density (BMD) in women from perimenopause to old age.

MATERIAL AND METHODS

A total of 117 women were allocated into three groups according to the reproductive stage (STRAW): perimenopausal (PEM, N = 28, mean age 44.8 ± 3.6), early postmenopausal (EPM, N = 36, mean age 51.4 ± 2.8) and late postmenopausal (LPM, N = 53; mean age 64.0 ± 1.7). Total body mass, body mass index (BMI), lean mass (LM), fat mass (FM), fat percentage (FP) and BMD at the lumbar spine (lBMD) and femoral neck (fBMD) were assessed.

RESULTS

BMI, FM, LM and BMD values decreased from PEM to LPM. The total effect of FM on fBMD and lBMD was of 42% and 8% for PEM, 28% and 33% for EMP and 9% and 1% for LPM respectively. Additionally, the total effect of LM on fBMD and lBMD was 48% and 3% for PEM, 54% and 53% for EMP and 9% and 11% for LPM women respectively.

CONCLUSION

BMI, LM, and FM decreased with aging. All these components had great influence on both fBMD and lBMD in EMP women. Conversely, in PEM these parameters only had influence on femoral BMD, but not on lumbar spine. These data suggests that LM is the most important component in BMD for women older than 50 years old, particularly in the hip.

How Does Fat Mass Change in the First Year After Bariatric Surgery? A Systemic Review and Meta-Analysis

This systematic review and meta-analysis investigated the time-course effect of different type of bariatric surgeries (BS) up to 1 year post-surgery on fat mass (FM) and body fat percentage (BFP) in patients with morbid obesity. We searched PubMed, Scopus, EMBASE, ISI web of science, and Cochrane databases from October 2002 until May 2020 with no restriction in the English language, to find studies examining the effect of BS on FM (kg) and BFP (%) in morbid obese patients. Meta-analysis of 103 studies carried out on data of 18,166 and 14,575 morbid obese patients following BS, showed that BS was associated with a substantial decrease in FM and BFP, respectively, in 1 month (- 8.17 kg [95% CI - 9.07, - 7.27] and - 1.51% [95% CI - 2.56, - 0.46]), 3 months (- 15.75 [95% CI - 17.49, - 14.0] and - 4.90 [95% CI - 5.97, - 3.83]), 6 months (- 22.51 [95% CI - 23.93, - 21.09] and - 8.56% [95% CI - 9.63, - 7.49]), and 12 months (- 29.69 [95% CI - 31.3, - 28.09] and - 13.49% [95% CI - 14.52, - 12.40]) after the surgery. In conclusion, BS was associated with sustained declines in FM and BFP, from 1 to 12 months, with no indication of plateau phase post-surgery post-operatively. The present study emphasizes that post-bariatric care should have more focus on FM loss during 1-year post-surgery to identify the patients at risk for fat loss plateau.