Bariatric Surgery and Osteoporosis

[Procedures of complementary medicine in rheumatology]

Patients with diseases of the musculoskeletal system are confronted with a large quantity of treatment offers based on methods of complementary medicine. Despite a considerable number of publications on this topic, the scientific evidence is still poor. This article focuses on Ayurvedic medicine (AM), traditional Chinese medicine (TCM), mind-body medicine and homeopathy. These procedures have a longstanding tradition of practice and each claims to have its own theoretical concept; however, the application in the field of rheumatology can only be recommended either for specific entities or, in the case of homeopathy, not at all. In addition, this article summarizes the evidence for dietary recommendations, nutritional supplements and herbal medicine in rheumatology. The latter topics are frequently discussed in the popular press and are a much-debated issue between physicians and patients; however, clear-cut recommendations for the application on a scientific basis are the exception and mainly consist of the endorsement to adhere to the principles of a Mediterranean diet.

Efficacy of multivitamin support following bariatric surgery in patients with obesity: a prospective observational study

PURPOSE

Bariatric surgery (BS), an effective treatment for severe obesity and its comorbidities, may result in micronutrient and vitamin deficiencies. This monocentric prospective observational study aimed at evaluating the efficacy of a specifically designed vitamin/mineral formula (Bariatrifast, BIOITALIA S.r.l., Italy) for preventing and treating micronutrient deficiencies in patients submitted to BS.

METHODS

Twenty patients with severe obesity (mean weight and BMI: 123.5 kg (range 88-174) and 43.3 kg/m2 (range 37-54) respectively) underwent BS (10 vertical sleeve gastrectomy VSG, 10 Roux-en-Y gastric bypass, RYGB). The mean age was 49.9 years (range 27-68). After a presurgical visit (V0), follow-up visits were performed at 1, 3, 6 and 12 months after surgery (V1-V4). Recorded data included weight, height and BMI. A complete blood count, measurement of ferritin, folic acid, vitamin B12, ionized calcium, 25 OH vitamin D, parathyroid hormone (PTH) were obtained. Following BS, patients started the daily oral multivitamin and mineral supplement.

RESULTS

All patients achieved a significant weight loss (mean - 34.7 ± 11.8 kg). No deficiencies of various vitamins/micronutrients were detected during the entire study period. The serum concentrations of vitamin B12, 25-OH Vitamin D and folic acid increased over the follow-up period compared with V0 (mean increase 243 ng/L, 23 µg /L, 8 µg/L, respectively). Compared to RYGB, patients who underwent sleeve gastrectomy showed higher levels of 25-OH vitamin D at V2, V3 and V4 (all p < 0.05), and higher levels of Vitamin B12 and folic acid at V4 (p < 0.05 and p < 0.005, respectively). No adverse events were reported.

CONCLUSION

Following VSG or RYGB, Bariatrifast administration was associated with normal values of essential micronutrients, and it was well-tolerated without evidence of gastrointestinal side effects. Clinical Trial Registration ClinicalTrials.gov, identifiers NCT06152965.

Patients who received sleeve gastrectomy have lower plasma osteopontin levels than those who did not

BACKGROUND

The aim of this study was to compare metabolic parameters, plasma Osteopontin (OPN) and Hepatocyte Growth Factor (HGF) levels between Sleeve Gastrectomy (SG) patients in their 6th post-operation month and healthy control patients.

METHODS

Height, weight, Body Mass Index (BMI) and laboratory parameters of 58 SG patients aged 18‒65 years (Group 1) and 46 healthy control patients (Group 2) were compared. In addition, preoperative and postoperative sixth-month BMI and laboratory parameters of the patients in Group 1 were compared.

RESULTS

The mean age and gender distributions of the groups were similar (p > 0.05). Mean BMI was 28.9 kg/m2 in Group 1 and 27 kg/m2 in Group 2 (p < 0.01). While plasma HGF levels were similar between both groups, plasma OPN levels were higher in Group 2 (p < 0.001). Fasting plasma glucose, total cholesterol, triglyceride, fasting plasma insulin and insulin resistance values were higher in Group 1, while alanine aminotransferase and aspartate aminotransferase levels were higher in Group 2 (p < 0.05). There was a strong correlation between plasma HGF and OPN levels in Group 1, but not in Group 2 (Rho = 0.805, p < 0.001).

CONCLUSION

OPN and HGF are promising biomarkers that can be used to better understand and detect problems related to obesity. The fact that patients in the early post-SG period had lower plasma OPN and similar plasma HGF compared to non-surgical patients of similar age and gender with higher BMI may be another favorable and previously unknown metabolic effect of SG.

The Effect of Diet Composition on the Post-operative Outcomes of Roux-en-Y Gastric Bypass in Mice

PURPOSE

Roux-en-Y gastric bypass (RYGB) leads to the improvement of many obesity-associated conditions. The degree to which post-operative macronutrient composition contributes to metabolic improvement after RYGB is understudied.

METHODS

A mouse model of RYGB was used to examine the effects of diet on the post-operative outcomes of RYGB. Obese mice underwent either Sham or RYGB surgery and were administered either chow or HFD and then monitored for an additional 8 weeks.

RESULTS

After RYGB, reductions to body weight, fat mass, and lean mass were similar regardless of diet. RYGB and HFD were independently detrimental to bone mineral density and plasma vitamin D levels. Independent of surgery, HFD accelerated hematopoietic stem and progenitor cell proliferation and differentiation and exhibited greater myeloid lineage commitment. Independent of diet, systemic iron deficiency was present after RYGB. In both Sham and RYGB groups, HFD increased energy expenditure. RYGB increased fecal energy loss, and HFD after RYGB increased fecal lipid content. RYGB lowered fasting glucose and liver glycogen levels but HFD had an opposing effect. Indices of insulin sensitivity improved independent of diet. HFD impaired improvements to dyslipidemia, NAFLD, and fibrosis.

CONCLUSION

Post-operative diet plays a significant role in determining the degree to which RYGB reverses obesity-induced metabolic abnormalities such as hyperglycemia, dyslipidemia, and NAFLD. Diet composition may be targeted in order to assist in the treatment of post-RYGB bone mineral density loss and vitamin D deficiency as well as to reverse myeloid lineage commitment. HFD after RYGB continues to pose a significant multidimensional health risk.

Management of Patients With Kidney Disease Undergoing Bariatric Surgery: A Multidisciplinary Approach

Bariatric surgery is increasingly recognized as a safe and effective treatment for obesity in patients with chronic kidney disease (CKD), including stages 4, 5, and 5D (on dialysis). Among the available surgical methods, sleeve gastrectomy (SG) is the most commonly performed weight loss procedure and is mainly done to facilitate kidney transplantation (KT). However, many KT candidates treated with SG remain on the transplant waiting list for months to years, with some never receiving a transplant. Therefore, appropriate candidates for SG must be selected, and post-SG management should address the unique needs of this population, with a focus on sustaining the metabolic benefits of surgery while minimizing potential side effects related to rapid weight loss which may inadvertently lead to muscle and bone catabolism. Multidisciplinary post-SG care in this population may lead to overall better health on the transplant waiting list, resulting in a higher percentage of post-SG patients ultimately receiving KT. To tailor the effective treatment for these patients, clinicians should acknowledge that patients with CKD stage 4-5D have different nutritional needs and are metabolically and psychosocially distinct from the general bariatric surgery population. Sarcopenia is highly prevalent and may be exacerbated by muscle catabolism following SG if not adequately addressed. Blood pressure, glucose, and bone metabolism are all affected by the CKD stage 4-5D, and therefore require distinct diagnostic and management approaches. Long-standing chronic disease, associated comorbidities, and low adherence to medical therapies require ongoing comprehensive psychosocial assessment and support. This paper aims to review and consolidate the existing literature concerning the intersection of CKD stage 4-5D and the consequences of SG. We also suggest future clinical outcome studies examining novel treatment approaches for this medically complex population.

Narrative Review of Effects of Glucagon-Like Peptide-1 Receptor Agonists on Bone Health in People Living with Obesity

Glucagon-like peptide-1 Receptor agonists (GLP-1Ras) such as liraglutide and semaglutide have been recently approved as medications for chronic weight management in people living with obesity (PwO); GLP-1 may enhance bone metabolism and improve bone quality. However, the effects of GLP-1Ras on skeletal health remain to be determined and that's the purpose of this narrative review. Nevertheless, bone consequences of intentional weight loss interventions in PwO are well known: (i) significant weight loss induced by caloric restriction and bariatric surgery results in accelerated bone turnover and bone loss, and (ii) unlike caloric restriction interventions, PwO experience a substantial deterioration in bone microarchitecture and strength associated with an increased risk of fracture after bariatric surgery especially malabsorptive procedures. Liraglutide seems to have a positive effect on bone material properties despite significant weight loss in several rodent models. However, most of positive effects on bone mineral density and microarchitecture were observed at concentration much higher than approved for obesity care in humans. No data have been reported in preclinical models with semaglutide. The current evidence of the effects of GLP-1Ra on bone health in PwO is limited. Indeed, studies on the use of GLP-1Ra mostly included patients with diabetes who were administered a dose used in this condition, did not have adequate bone parameters as primary endpoints, and had short follow-up periods. Further studies are needed to investigate the bone impact of GLP-1Ra, dual- and triple-receptor agonists for GLP-1, glucose-dependent insulin releasing polypeptide (GIP), and glucagon in PwO.

The Effects of Bariatric Surgery on Pharmacokinetics of Drugs: a Review of Current Evidence

PURPOSE OF REVIEW

Obesity constitutes a major public health concern and has been recognized as an epidemic. To date, bariatric surgery remains the most effective way for substantial long-lasting weight loss in severe obesity. The purpose of this review is to summarize how the pharmacokinetics of drugs are affected by the most common types of bariatric surgery, i.e., Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG).

RECENT FINDINGS

Limited data are available regarding the changes in pharmacokinetics of drugs after bariatric surgery. The lack of existing guidelines may lead patients to experience drug toxicity or therapeutic undertreatment. Pharmacokinetic parameters that need to be taken into consideration postoperatively include gastric motility, gastric volume, pH, surface area, bile secretions, carrier proteins, and first-pass metabolism. For drugs with a narrow therapeutic index, other factors need to be monitored closely, including plasma drug levels, patients' clinical outcomes, and laboratory markers. Patients should be followed up frequently and treated in accordance with their response to the drug therapy. Bariatric surgery may affect the pharmacokinetics of various drugs, due to the resultant anatomical changes and the substantial weight loss. Therefore, there is a need to identify those potential changes and adjust patients' medication doses in order to achieve higher efficacy and avoid toxicity.

The Impact of Interventional Weight Loss on Bone Marrow Adipose Tissue in People Living with Obesity and Its Connection to Bone Metabolism

This review focuses on providing physicians with insights into the complex relationship between bone marrow adipose tissue (BMAT) and bone health, in the context of weight loss through caloric restriction or metabolic and bariatric surgery (MBS), in people living with obesity (PwO). We summarize the complex relationship between BMAT and bone health, provide an overview of noninvasive imaging techniques to quantify human BMAT, and discuss clinical studies measuring BMAT in PwO before and after weight loss. The relationship between BMAT and bone is subject to variations based on factors such as age, sex, menopausal status, skeletal sites, nutritional status, and metabolic conditions. The Bone Marrow Adiposity Society (BMAS) recommends standardizing imaging protocols to increase comparability across studies and sites, they have identified both water-fat imaging (WFI) and spectroscopy (1H-MRS) as accepted standards for in vivo quantification of BMAT. Clinical studies measuring BMAT in PwO are limited and have shown contradictory results. However, BMAT tends to be higher in patients with the highest visceral adiposity, and inverse associations between BMAT and bone mineral density (BMD) have been consistently found in PwO. Furthermore, BMAT levels tend to decrease after caloric restriction-induced weight loss. Although weight loss was associated with overall fat loss, a reduction in BMAT did not always follow the changes in fat volume in other tissues. The effects of MBS on BMAT are not consistent among the studies, which is at least partly related to the differences in the study population, skeletal site, and duration of the follow-up. Overall, gastric bypass appears to decrease BMAT, particularly in patients with diabetes and postmenopausal women, whereas sleeve gastrectomy appears to increase BMAT. More research is necessary to evaluate changes in BMAT and its connection to bone metabolism, either in PwO or in cases of weight loss through caloric restriction or MBS, to better understand the role of BMAT in this context and determine the local or systemic factors involved.

Long-term trajectories of bone metabolism parameters and bone mineral density (BMD) in obese patients treated with metabolic surgery: a real-world, retrospective study

PURPOSE

Potential negative effects of metabolic surgery on skeletal integrity remain a concern, since long-term data of different surgical approaches are poor. This study aimed to describe changes in bone metabolism in subjects with obesity undergoing both Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG).

METHODS

A single center, retrospective, observational clinical study on real-world data was performed enrolling subjects undergoing metabolic surgery.

RESULTS

123 subjects were enrolled (males 31: females 92; ages 48.2 ± 7.9 years). All patients were evaluated until 16.9 ± 8.1 months after surgery, while a small group was evaluated up to 4.5 years. All patients were treated after surgery with calcium and vitamin D integration. Both calcium and phosphate serum levels significantly increased after metabolic surgery and remained stable during follow-up. These trends did not differ between RYGB and SG (p = 0.245). Ca/P ratio decreased after surgery compared to baseline (p < 0.001) and this decrease remained among follow-up visits. While 24-h urinary calcium remained stable across all visits, 24-h urinary phosphate showed lower levels after surgery (p = 0.014), also according to surgery technique. Parathyroid hormone decreased (p < 0.001) and both vitamin D (p < 0.001) and C-terminal telopeptide of type I collagen (p = 0.001) increased after surgery.

CONCLUSION

We demonstrated that calcium and phosphorous metabolism shows slight modification even after several years since metabolic surgery, irrespective of calcium and vitamin D supplementation. This different set point is characterized by a phosphate serum levels increase, together with a persistent bone loss, suggesting that supplementation alone may not ensure the maintenance of bone health in these patients.

Strategies to reduce the onset of sleeve gastrectomy associated bone loss (STRONG BONES): Trial design and methods

Background

Despite recognized improvements in obesity-related comorbidities, mounting evidence implicates surgical weight loss in the onset of skeletal fragility. Sleeve gastrectomy (SG) is the most commonly performed bariatric procedure and is associated with 3-7% axial bone loss in the year following surgery. Bisphosphonates are FDA-approved medications for the prevention and treatment of age-related bone loss and may represent a strategy to reduce bone loss following SG surgery.

Methods

The Strategies to Reduce the Onset of Sleeve Gastrectomy Associated Bone Loss (STRONG BONES) trial (NCT04922333) is designed to definitively test whether monthly administration of the bisphosphonate, risedronate, for six months can effectively counter SG-associated bone loss. Approximately 120 middle-aged and older (≥40 years) SG patients will be randomized to six months of risedronate or placebo treatment, with skeletal outcomes assessed at baseline, six, and 12-months post-surgery. The primary outcome of the trial is 12-month change in total hip areal bone mineral density (aBMD), measured by dual energy x-ray absorptiometry (DXA). This will be complemented by DXA-acquired aBMD assessment at other skeletal sites and quantitative computed tomography (QCT) derived changes in bone quality. Change in muscle mass and function will also be assessed, as well as biomarkers of bone health, turnover, and crosstalk, providing mechanistic insight into intervention-related changes to the bone-muscle unit.

Discussion

Results from the STRONG BONES trial have the potential to influence current clinical practice by determining the ability of bisphosphonate use to mitigate bone loss and concomitant fracture risk in middle-aged and older SG patients.

Long-term outcomes after gastric bypass surgery in patients with craniopharyngioma-related hypothalamic obesity-Three cases with 7, 8, and 14 years follow-up

INTRODUCTION

Craniopharyngioma is a brain tumor, resection which often results in hypothalamic damage leading to severe obesity. While small case series and case-control studies have shown the benefits of bariatric surgery in patients with craniopharyngioma-related hypothalamic obesity, long-term results (>5 years) have not been reported so far.

METHODS

We analyzed data from 3 cases with craniopharyngioma-related hypothalamic obesity who had undergone (one proximal, two very long limb distal) Roux-en Y gastric bypass (RYGB) surgery 7, 8, and 14 years before their latest follow-up visit.

RESULTS

Percentage of total weight loss varied across the 3 patients (11%, 26%, 32%). Preexisting type 2 diabetes markedly improved in 2 patients with one showing a temporary and one a persisting remission. At RYGB surgery one patient was diagnosed to have liver cirrhosis (intraoperative biopsy), but liver function remained stable or even improved during a 7-year follow-up period. One patient required proximalisation of lower anastomosis (distal RYGB) because of severe hypoproteinemia and diarrhea which resolved after revision. Another patient temporarily developed alcohol abuse that led to weight regain, but his weight decreased when alcohol consumption became under control. Importantly, all three patients stated in a standardized questionnaire that they have benefited and that they would recommend RYGB surgery to another person.

CONCLUSION

Despite showing an unsatisfying weight loss result in one patient and distinct complications in the other two patients, all patients clearly showed long-term persisting benefits. Moreover, self-reported outcomes confirm that it was the right decision to recommend RYGB to our patients displaying craniopharyngioma-related hypothalamic obesity.

Postoperative Osteoporosis in Subjects with Morbid Obesity Undergoing Bariatric Surgery with Gastric Bypass or Sleeve Gastrectomy

Obesity has become a worldwide epidemic accompanied by adverse health effects. The limited efficiency of traditional weight reduction regimens has led to a substantial increase in the use of bariatric surgery. Today, sleeve gastrectomy (SG) and Roux-en-Y-gastric bypass (RYGB) are the most used procedures. The present narrative review focuses on the risk of developing postoperative osteoporosis and summarizes some of the most relevant micronutrient deficiencies associated with RYGB and SG. Preoperatively, the dietary habits of obese individuals might lead to precipitated deficiencies in vitamin D and other nutrients affecting bone mineral metabolism. Bariatric surgery with SG or RYGB can aggravate these deficiencies. The various surgical procedures appear to affect nutrient absorption differently. Being purely restrictive, SG may particularly affect the absorption of vitamin B12 and also vitamin D. In contrast, RYGB has a more profound impact on the absorption of fat-soluble vitamins and other nutrients, although both surgical methods induce only a mild protein deficiency. Despite adequate supplementation of calcium and vitamin D, osteoporosis may still occur after the surgery. This might be due to deficiencies in other micronutrients, e.g., vitamin K and zinc. Regular follow-ups with individual assessments and nutritional advice are indispensable to prevent osteoporosis and other adverse postoperative issues.

An Evaluation of the Implementation of the European Calcified Tissue Society Recommendations on the Prevention and Treatment of Osteoporosis Secondary to Bariatric Surgery

The purpose of this study was to evaluate the implementation of the European Calcified Tissue Society (ECTS) 2022 recommendations on the prevention and treatment of osteoporosis secondary to bariatric surgery. The ECTS 2022 recommendations were applied in a retrospective cohort of postmenopausal women and men aged 50 years and older who were undergoing or had already undergone bariatric surgery. Osteoporosis medication was indicated if any of the following criteria were met: (i) history of recent (within 2 years) fragility fracture after the age of 40 years, (ii) BMD T score ≤ -2 at any of the sites of measurement, and (iii) FRAX^® ≥ 20% for major osteoporotic fractures and/or ≥3% for hip fractures. Of the 170 patients (144 women, mean age 59 (55 to 63) years) included between February 2019 and March 2022, 33 were eligible for osteoporosis medication based on the ECTS 2022 recommendations, i.e., a prevalence of 19.6% [CI95%: 13.9%; 26.5%]. Most patients met the BMD T score ≤ -2 criterion (n = 25/170, 14.7% [CI95%: 9.7%; 20.9%]) and/or the history of recent fragility fracture criterion (n = 12/170, 7.1% [CI95%: 3.7%; 12.0%]). In this study, a fifth of our population was found to be eligible for osteoporosis medication after the application of the ECTS 2022 recommendations.

Changes in Bone Turnover Markers after Roux-en-Y Gastric Bypass Versus Sleeve Gastrectomy: a Systematic Review and Meta-Analysis

This systematic review and meta-analysis was performed to compare the alterations in bone turnover markers between SG and RYGB. A literature search was conducted in PubMed, Medline, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases to find the studies. There was significant less increment in osteocalcin [WMD =  - 5.98, 95% CI (- 9.30, - 2.47) P < 0.01] and parathyroid hormone (PTH) [WMD =  - 9.59, 95% CI (- 15.02, - 4.16) P < 0.01] in the SG group compared to the RYGB group. No significant differences were seen in change of C-terminal telopeptide of type I collagen (CTX), N-terminal propeptide of type I collagen (PINP), Ca, and 25(OH)-D between SG and RYGB groups. According to our meta-analysis, bone formation markers appear to have more increment following RYGB than SG. This observation is accompanied by a larger increase in PTH after RYGB patients compared to SG patients. PROSPERO: CRD42022308985.

The PYY/Y2R-deficient male mouse is not protected from bone loss due to Roux-en-Y gastric bypass

BACKGROUND

Peptide YY (PYY) is an anorexigenic gut hormone that also has anti-osteogenic effects, inhibiting osteoblastic activity and inducing catabolic effects. It has been postulated that increases in PYY after Roux-en-Y gastric bypass (RYGB) contribute to declines in bone mineral density (BMD) and increases in bone turnover. The aim of this study is to determine the role of the PYY Y2-receptor in mediating bone loss post-RYGB in mice.

METHODS

We compared adult male wildtype (WT) and PYY Y2 receptor-deficient (KO) C57BL/6 mice that received RYGB (WT: n = 8; KO: n = 9), with sham-operated mice (Sham; WT: n = 9; KO: n = 10) and mice that were food-restricted to match the weights of the RYGB-treated group (Weight-Matched, WM; WT: n = 7; KO: n = 5). RYGB or sham surgery was performed at 15-16 weeks of age, and mice sacrificed 21 weeks later. We characterized bone microarchitecture with micro-computed tomography (μCT) at the distal femur (trabecular) and femoral midshaft (cortical). Differences in body weight, bone microarchitecture and biochemical bone markers (parathyroid hormone, PTH; C-telopeptide, CTX; and type 1 procollagen, P1NP) were compared using 2-factor ANOVA with Tukey's adjustments for multiple comparisons.

RESULTS

Body weights were similar in the WT-RYGB, WT-WM, KO-RYGB, and KO-WM: 41-44 g; these groups weighed significantly less than the Sham surgery groups: 55-57 g. Trabecular BMD was 31-43 % lower in RYGB mice than either Sham or WM in WT and KO groups. This deficiency in trabecular bone was accompanied by a lower trabecular number (19 %-23 %), thickness (22 %-30 %) and increased trabecular spacing (25 %-34 %) in WT and KO groups (p < 0.001 for all comparisons vs. RYGB). RYGB led to lower cortical thickness, cortical tissue mineral density, and cortical bone area fraction as compared to Sham and WM in WT and KO groups (p ≤ 0.004 for all). There were no interactions between genotype and bone microarchitecture, with patterns of response to RYGB similar in both WT and KO groups. CTX and P1NP were significantly higher in RYGB mice than WM in WT and KO groups. PTH did not differ among groups.

CONCLUSIONS

RYGB induced greater trabecular and cortical deficits and high bone turnover than observed in weight-matched mice, with a similar pattern in the WT and Y2RKO mice. Thus, skeletal effects of RYGB are independent of weight loss, and furthermore, PYY signaling through Y2R is not a key mediator of bone loss post-RYGB.

CT evaluation of bone fragility 2 years after bariatric surgery: an observational study

INTRODUCTION

The objectives were to evaluate bone fragility on computed tomography (CT) in patients with obesity before and 2 years after bariatric surgery and to identify risk factors for a decrease in the scanographic bone attenuation coefficient of the first lumbar vertebra (SBAC-L1).

MATERIALS AND METHODS

Patients with obesity who underwent bariatric surgery and CT before and 2 years (± 6 months) after bariatric surgery were included. SBAC-L1 was measured on CT with a fracture threshold at 145 HU.

RESULTS

78 patients were included, 85.9% women, mean age of 48.5 years (± 11.4); the mean BMI was 46.2 kg/m² (± 7) before surgery and 29.8 kg/m² (± 6.7) 2 years after surgery. There was a significant change in SBAC-L1 2 years after surgery (p = 0.037). In multivariate analysis, the risk factors for having an SBAC-L1 ≤ 145HU 2 years after bariatric surgery in those with an SBAC-L1 > 145HU before surgery were age and sex, with men and older patients having a higher risk (OR 32.6, CI 95% [1.86-568.77], and OR 0.85, CI 95% [0.74-0.98], respectively).

CONCLUSION

SBAC-L1 was significantly lower two years after bariatric surgery. Men sex and older patients were the risk factors for having an SBAC-L1 below the fracture threshold 2 years after surgery.

Diet Management of Patients with Chronic Kidney Disease in Bariatric Surgery

Morbid obesity is considered a civilization disease of the 21st century. Not only does obesity increase mortality, but it is also the most important cause of the shortening life expectancy in the modern world. Obesity is associated with many metabolic abnormalities: dyslipidemia, hyperglycemia, cardiovascular diseases, and others. An increasing number of patients diagnosed with chronic kidney disease (CKD) are obese. Numerous additional disorders associated with impaired kidney function make it difficult to conduct slimming therapy and may also be associated with a greater number of complications than in people with normal kidney function. Currently available treatments for obesity include lifestyle modification, pharmacotherapy, and bariatric surgery (BS). There are no precise recommendations on how to reduce excess body weight in patients with CKD treated conservatively, undergoing chronic dialysis, or after kidney transplantation. The aim of this study was to analyze studies on the bariatric treatment of obesity in this group of people, as well as to compare the recommendations typical for bariatrics and CKD.

[Indications in Obesity Therapy - Surgeons First?]

Obesity is a growing problem worldwide. For the first time since 2010, more people have been overweight than underweight. In particular, obesity-associated diseases, above all type 2 diabetes mellitus, pose enormous challenges to the healthcare system. On July 3, 2020, the German Bundestag recognised obesity as a disease and initiated the development of a diseases management program (DMP), which is currently being drawn up. So far, the indication for treatment of obesity in Germany has been based on the S3 guideline "Surgery of obesity and metabolic diseases" of the DGAV from 2018 and the S3 guideline "Prevention and therapy of obesity" of the German Obesity Society e. V. from 2014. This article gives an overview of the currently available conservative, medical, endoscopic and surgical treatment methods for overweight and obesity in Germany and explains the indications. Against the background of the reorientation of obesity treatment as a part of the DMP and the forthcoming revisions of the guidelines, the previous indication should be discussed critically. The scientific findings of the last few years show that surgical treatment of obesity not only achieves the greatest weight loss in the long term, but also that obesity-associated diseases are then treated more effectively and overall mortality is reduced significantly more effectively than with conservative treatment.

Musculoskeletal effects of obesity and bariatric surgery – a narrative review

Obesity affects several areas of the human body, leading to increased morbidity and mortality and the likelihood of other diseases, such as type 2 diabetes mellitus, cardiovascular diseases and musculoskeletal disorders. These conditions predispose to bone fractures and sarcopenic obesity, defined by the presence of an obesity-associated decrease in muscle mass and strength. Both bone fragility and sarcopenic obesity disease are consequences of several factors, such as a low degree of chronic inflammation, insulin resistance, hormonal changes, nutritional deficiencies, ectopic fat deposits and sedentary lifestyle. The diagnosis of obesity-related musculoskeletal disorders is limited by the lack of sarcopenia criteria and lower accuracy of bone mineral density measurement by dual-energy X-ray absorptiometry in overweight people. Reducing body weight provides undeniable benefits to this population, however treating cases of severe obesity with bariatric surgery can cause even greater damage to bone and muscle health, especially in the long term. The mechanisms involved in this process are not yet fully understood, but factors related to nutrient malabsorption and mechanical discharge as well as changes in gut hormones, adipokines and bone marrow adiposity should be taken into account. Depending on the surgical technique performed, greater musculoskeletal damage may occur, especially in cases of malabsorptive surgeries such as Roux-en-Y gastric bypass, when compared to restrictive techniques such as sleeve gastrectomy. This difference is probably due to greater weight loss, nutrient malabsorption and important hormonal changes that occur as a consequence of the diversion of intestinal transit and loss of greater absorptive surface. Thus, people undergoing bariatric procedures, especially malabsorptive ones, should have their musculoskeletal health supervised to allow early diagnosis and appropriate therapeutic interventions to prevent osteoporotic fractures and preserve the functionality of the skeletal muscles.

BONE HEALTH ASSESSMENT OF ELDERLY PATIENTS UNDERGOING BARIATRIC SURGERY

BACKGROUND

Bariatric surgery promotes changes in body composition, that can include the loss of bone mineral density (BMD). There is a lack of studies on the evolution of bone health of elderly people who underwent bariatric surgery, in general, and when comparing the gastric bypass (GB) and sleeve gastrectomy (SG) techniques.

OBJECTIVE

To evaluate the bone health of elderly patients with obesity undergoing bariatric surgery.

METHODS

This is a prospective randomized clinical study, that was carried out with individuals of both sexes, ≥65 years, undergoing GB or SG and who met the inclusion criteria. Age, gender and comorbidities (type 2 diabetes mellitus, arterial hypertension, dyslipidemia and osteoarthrosis) were collected and analyzed at baseline. Anthropometric data (weight, body mass index, percentage of weight loss, percentage of excess weight loss), laboratory tests related to bone health and bone mineral density were analyzed before and 24 months after surgery.

RESULTS

A total of 36 patients (GB, n=18; SG, n=18) were evaluated. At baseline, except for sex and preoperative body mass index, which was higher in GB, groups were similar. After 24 months, GB was superior for weight loss (%WL) and excess weight loss (%EWL). Regarding bone health, a significant decrease of BMD was observed in the spine, total proximal femur and femoral neck in all groups, with an average decrease of 5.1%, 10.5% and 15.1%, respectively. In addition, the observed decrease in BMD was up to 25% in the total femur after 24 months, six patients went from normal BMD to osteopenia and one from osteopenia to osteoporosis. There was no difference in parathormone values. However, there was an association between the increase in parathormone and the decrease in BMD in the spine, mainly in the GB group. There was no association between %WL and %EWL with the reduction in BMD.

CONCLUSION

Bariatric surgery was related to the reduction of BMD in elderly patients, but there was no statistical difference between the two surgical techniques.

Nutritional Outcomes One Year after One Anastomosis Gastric Bypass Compared to Sleeve Gastrectomy

One Anastomosis Gastric Bypass (OAGB) and Sleeve Gastrectomy (SG) are the most common bariatric procedures performed worldwide. SG is a restrictive procedure whereas OAGB involves malabsorption as well, supposing a risk of deficiency development post OAGB. The aim of the study was to compare nutritional deficiencies and metabolic markers one year after the procedures, while adhering to the current protocols. Retrospective analysis was performed for data on 60 adults undergoing primary OAGB, compared to 60 undergoing primary SG. Mean pre-surgery BMI for SG was 42.7 kg/m² and 43.3 kg/m² for OAGB. A multidisciplinary team followed up with the patients at least 3 times during the first year. Mean weight loss was 39.0 kg for SG and 44.1 kg for OAGB. The OAGB group presented a significantly sharper decline in T.Chol and a trend for sharper LDL decrease; a higher increase in folate and a trend for a greater decrease in albumin and hemoglobin were observed in OAGB. For vitamin B12, D, iron and ferritin, no difference was observed between the treatment groups, although there were some in-group differences. Nutritional recommendations and adopted supplement plans minimize the risk of deficiencies and result in improvement in metabolic biomarkers one year after OAGB, which was comparable to SG.

[Obesity - a chronic disease requiring treatment]

The globally increasing prevalence of obesity represents a key medical and socioeconomic challenge. Due to related comorbidities and complications such as arterial hypertension, diabetes mellitus, fatty liver disease, and arteriosclerosis, obesity leads to a significant statistical reduction in lifespan. Currently, bariatric surgery is the most effective approach to manage body weight and comorbidities while lifestyle intervention as basic obesity therapy and medical treatment often do not lead to sufficient and sustainable weight loss. However, recent medical approaches show now promising effects on weight control and might close the gap towards bariatric surgical procedures. For instance, semaglutide has been approved by EMA in January 2022 for medical treatment of obesity concomitant to basic lifestyle therapy in adults with a BMI of ≥ 30 kg/m² or ≥ 27 kg/m² and weight-related comorbidity. Apart from weight control, improvement in cardiometabolic risk factors can be achieved with this treatment. Moreover, other drugs, mostly based on incretin mono- or multiagonism, are currently developed and may open further effective treatment options for obesity and its complications in the near future.On a health political level, first steps for the development of a structured treatment program (DMP) for obesity are in progress to enable early guideline-based and structured treatment of obesity, and to prevent the obesity associated complications.

Secondary Osteoporosis and Metabolic Bone Diseases

Fragility fracture is a worldwide problem and a main cause of disability and impaired quality of life. It is primarily caused by osteoporosis, characterized by impaired bone quantity and or quality. Proper diagnosis of osteoporosis is essential for prevention of fragility fractures. Osteoporosis can be primary in postmenopausal women because of estrogen deficiency. Secondary forms of osteoporosis are not uncommon in both men and women. Most systemic illnesses and organ dysfunction can lead to osteoporosis. The kidney plays a crucial role in maintaining physiological bone homeostasis by controlling minerals, electrolytes, acid-base, vitamin D and parathyroid function. Chronic kidney disease with its uremic milieu disturbs this balance, leading to renal osteodystrophy. Diabetes mellitus represents the most common secondary cause of osteoporosis. Thyroid and parathyroid disorders can dysregulate the osteoblast/osteoclast functions. Gastrointestinal disorders, malnutrition and malabsorption can result in mineral and vitamin D deficiencies and bone loss. Patients with chronic liver disease have a higher risk of fracture due to hepatic osteodystrophy. Proinflammatory cytokines in infectious, autoimmune, and hematological disorders can stimulate osteoclastogenesis, leading to osteoporosis. Moreover, drug-induced osteoporosis is not uncommon. In this review, we focus on causes, pathogenesis, and management of secondary osteoporosis.

Fracture risk following bariatric surgery: a systematic review and meta-analysis

Bariatric surgery may negatively impact bone health. We aimed to compare fracture risk following bariatric surgery by type (malabsorptive, restrictive), or to non-surgical weight loss, or to controls with obesity. We systematically searched four databases from inception until October 2020. We included observational and interventional studies on adults. We screened articles and abstracted data in duplicate and independently and assessed the risk of bias. We conducted random-effects model meta-analyses (Review Manager v5.3), to calculate the relative risk of any or site-specific fracture (CRD42019128536). We identified four trials of unclear-to-high risk of bias and 15 observational studies of fair-to-good quality. Data on fracture risk following bariatric surgery compared to medical weight loss is scarce and limited by the small number of participants. In observational studies, at a mean/median post-operative follow-up > 2 years, the relative risk of any fracture was 45% (p < 0.001) and 61% (p = 0.04) higher following malabsorptive procedures compared to obese controls and restrictive procedures, respectively, with moderate to high heterogeneity. Site-specific relative fracture risk (hip and wrist) was one- to two-folds higher post malabsorptive procedures compared to obese controls or restrictive procedures. The risks of any and of site-specific fracture were not increased following restrictive procedures compared to obese controls. Fracture risk seems to increase following malabsorptive bariatric surgeries, at a mean/median follow-up > 2 years. The risk is not increased with restrictive surgeries. The available evidence has several limitations. A prospective and rigorous long-term follow-up of patients following bariatric surgery is needed for a better assessment of their fracture risk with aging.

Nutritional Deficiencies Before and After Bariatric Surgery: Prevention and Treatment

PURPOSE OF REVIEW

Bariatric surgery has the unique ability to drive substantial and sustainable weight loss in people living with obesity. Non-reversibility of these surgical techniques provides lifelong benefits but entails the need for continuous medical follow-up. The purpose of the current paper is to review and summarize current data on nutritional deficiencies in patients before and after bariatric surgery.

RECENT FINDINGS

The cornerstone of preventing the emergence of disorders related to nutritional deficiencies is preoperative screening and correct supplementation since they may be exacerbated postoperatively. Following guidelines in conjunction to a lifelong personalized medical approach is of high importance. Bariatric surgery is a well-studied successful and durable means of weight loss that may lead to nutritional deficiencies. There is, thus, a medical need for careful monitoring and treatment of micro- and macronutrient deficiencies by an experienced multidisciplinary team.

The Effect of Exercise for the Prevention of Bone Mass After Bariatric Surgery: a Systematic Review and Meta-analysis

We aimed to assess if exercise applied after bariatric surgery (BS) improves bone mineral density (BMD) compared to usual care. Systematic search was conducted up to January 2021. Effect measures were determined using standardized mean difference (SMD) with 95% confidence interval (CI). Certainty evidence was assessed according to GRADE. Four clinical trials encompassing 340 patients were included. Exercise induced a positive BMD effect at total hip (SMD = 0.37 [95% CI 0.02, 0.71]; very low certainty evidence), femoral neck (SMD = 0.63 [95% CI 0.19, 1.06]; low certainty evidence), lumbar spine (SMD = 0.41 [95% CI 0.19, 0.62]; low certainty evidence), and 1/3 radius (SMD = 0.58 [95% CI 0.19, 0.97]; low certainty evidence). Exercise undertaken after BS seems to induce a positive effect on BMD.

Bile acids, gut microbiota and metabolic surgery

Metabolic surgery, or bariatric surgery, is currently the most effective approach for treating obesity and its complications. Vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB) are the top two types of commonly performed metabolic surgery now. The precise mechanisms of how the surgeries work are still unclear, therefore much research has been conducted in this area. Gut hormones such as GLP-1 and PYY have been studied extensively in the context of metabolic surgery because they both participate in satiety and glucose homeostasis. Bile acids, whose functions cover intestinal lipid absorption and various aspects of metabolic regulation via the action of FXR, TGR5, and other bile acid receptors, have also been actively investigated as potential mediators of metabolic surgery. Additionally, gut microbiota and their metabolites have also been studied because they can affect metabolic health. The current review summarizes and compares the recent scientific progress made on identifying the mechanisms of RYGB and VSG. One of the long-term goals of metabolic/bariatric surgery research is to develop new pharmacotherapeutic options for the treatment of obesity and diabetes. Because obesity is a growing health concern worldwide, there is a dire need in developing novel non-invasive treatment options.

Bone Response to Weight Loss Following Bariatric Surgery

Obesity is a global health challenge that warrants effective treatments to avoid its multiple comorbidities. Bariatric surgery, a cornerstone treatment to control bodyweight excess and relieve the health-related burdens of obesity, can promote accelerated bone loss and affect skeletal strength, particularly after malabsorptive and mixed surgical procedures, and probably after restrictive surgeries. The increase in bone resorption markers occurs early and persist for up to 12 months or longer after bariatric surgery, while bone formation markers increase but to a lesser extent, suggesting a potential uncoupling process between resorption and formation. The skeletal response to bariatric surgery, as investigated by dual-energy X-ray absorptiometry (DXA), has shown significant loss in bone mineral density (BMD) at the hip with less consistent results for the lumbar spine. Supporting DXA studies, analyses by high-resolution peripheral quantitative computed tomography (HR-pQCT) showed lower cortical density and thickness, higher cortical porosity, and lower trabecular density and number for up to 5 years after bariatric surgery. These alterations translate into an increased risk of fall injury, which contributes to increase the fracture risk in patients who have been subjected to bariatric surgery procedures. As bone deterioration continues for years following bariatric surgery, the fracture risk does not seem to be dependent on acute weight loss but, rather, is a chronic condition with an increasing impact over time. Among the post-bariatric surgery mechanisms that have been claimed to act globally on bone health, there is evidence that micro- and macro-nutrient malabsorptive factors, mechanical unloading and changes in molecules partaking in the crosstalk between adipose tissue, bone and muscle may play a determining role. Given these circumstances, it is conceivable that bone health should be adequately investigated in candidates to bariatric surgery through bone-specific work-up and dedicated postsurgical follow-up. Specific protocols of nutrients supplementation, motor activity, structured rehabilitative programs and, when needed, targeted therapeutic strategies should be deemed as an integral part of post-bariatric surgery clinical support.

Bariatric surgery and skeletal health: A narrative review and position statement for management by the European Calcified Tissue Society (ECTS)

CONTEXT

Numerous studies have demonstrated detrimental skeletal consequences following bariatric surgery.

METHODS

A working group of the European Calcified Tissue Society (ECTS) performed an updated review of existing literature on changes of bone turnover markers (BTMs), bone mineral density (BMD), and fracture risk following bariatric surgery and provided advice on management based on expert opinion.

LITERATURE REVIEW

Based on observational studies, bariatric surgery is associated with a 21-44% higher risk of all fractures. Fracture risk is time-dependent and increases approximately 3 years after bariatric surgery. The bariatric procedures that have a malabsorptive component (including Roux-en-Y Gastric bypass (RYGB) and biliopancreatic diversion (BPD)) have clearly been associated with the highest risk of fracture. The extent of high-turnover bone loss suggests a severe skeletal insult. This is associated with diminished bone strength and compromised microarchitecture. RYGB was the most performed bariatric procedure worldwide until very recently, when sleeve gastrectomy (SG) became more prominent. There is growing evidence that RYGB is associated with greater reduction in BMD, greater increase in BTMs, and higher risk of fractures compared with SG but RCTs on optimal management are still lacking.

EXPERT OPINION

In all patients, it is mandatory to treat vitamin D deficiency, to achieve adequate daily calcium and protein intake and to promote physical activity before and following bariatric surgery. In post-menopausal women and men older than 50 years, osteoporosis treatment would be reasonable in the presence of any of the following criteria: i) history of recent fragility fracture after 40 years of age, ii) BMD T-score ≤ -2 at hip or spine, iii) FRAX score with femoral neck BMD exceeding 20% for the 10-year major osteoporotic fracture probability or exceeding 3% for hip fracture. Zoledronate as first choice should be preferred due to intolerance of oral formulations and malabsorption. Zoledronate should be used with caution due to hypocemia risk. It is recommended to ensure adequate 25-OH vitamin D level and calcium supplementation before administering zoledronate.

CONCLUSIONS

The bariatric procedures that have a malabsorptive component have been associated with the highest turnover bone loss and risk of fracture. There is a knowledge gap on osteoporosis treatment in patients undergoing bariatric surgery. More research is necessary to direct and support guidelines.

A comparison of changes in bone turnover markers after gastric bypass and sleeve gastrectomy, and their association with markers of interest

BACKGROUND

It is still debated whether differences in bone turnover markers (BTMs) exist between the 2 most popular bariatric surgery procedures (Roux-en-Y gastric bypass [RYGB] and sleeve gastrectomy [SG]).

OBJECTIVES

To compare changes in BTMs after RYGB and SG, and to investigate their association with predefined markers of interest.

SETTING

University hospital, Lille, France.

METHODS

An ancillary investigation of a prospective cohort was conducted. SG patients with severe obesity ≥40 years were matched one-to-one to RYGB patients for age, sex, body mass index (BMI), and menopausal status. BTMs, as well as predefined markers of interest, were measured at baseline, 12, and 24 months after bariatric surgery.

RESULTS

Sixty-four patients (66% women) had a mean (standard deviation [SD]) age of 49.6 years (5.1) and a mean (SD) BMI of 45.0 kg/m² (6.0). From baseline to 12 months, a significant increase in BTMs was observed in both groups (P < .001). Moreover, RYGB was associated with a greater increase in C-terminal telopeptide (β-CTX) and procollagen type 1 N-terminal propeptide (PINP) compared with SG (P < .0001). From 12 to 24 months, a significant decrease in BTMs was observed in both groups, but no significant differences were found between RYGB and SG. However, BTMs did not return to baseline levels. The changes in PINP and β-CTX at 12 months were independently associated with the type of surgical procedure, after adjusting for weight or each predefined marker of interest (all P < .0001).

CONCLUSION

RYGB was associated with a greater increase in BTMs than SG at 12 and 24 months.

Nutritional intake and bone health

Osteoporotic or fragility fractures affect one in two women and one in five men who are older than 50. These events are associated with substantial morbidity, increased mortality, and an impaired quality of life. Recommended general measures for fragility fracture prevention include a balanced diet with an optimal protein and calcium intake and vitamin D sufficiency, together with regular weight-bearing physical exercise. In this narrative Review, we discuss the role of nutrients, foods, and dietary patterns in maintaining bone health. Much of this information comes from observational studies. Bone mineral density, microstructure-estimated bone strength, and trabecular and cortical microstructure are positively associated with total protein intake. Several studies indicate that fracture risk might be lower with a higher dietary protein intake, provided that the calcium supply is sufficient. Dairy products are a valuable source of these two nutrients. Hip fracture risk appears to be lower in consumers of dairy products, particularly fermented dairy products. Consuming less than five servings per day of fruit and vegetables is associated with a higher hip fracture risk. Adherence to a Mediterranean diet or to a prudent diet is associated with a lower fracture risk. These various nutrients and dietary patterns influence gut microbiota composition or function, or both. The conclusions of this Review emphasise the importance of a balanced diet including minerals, protein, and fruit and vegetables for bone health and in the prevention of fragility fractures.

Characteristics of Patients Reporting Presumed Problematic Drinking Behavior After Gastric Bypass: Exploring Long-Term Data From the BAROBS Study

OBJECTIVE

To explore patients' long-term experiences with drinking alcohol after Roux-n-Y gastric bypass (RYGB) for conceptualizing what may indicate problematic drinking behavior after bariatric surgery.

STUDY DESIGN

Three-center, observational study.

PATIENTS

546 adult patients undergoing RYGB in the period 2003-2009 in Norway.

MAIN OUTCOME MEASURES

Self-reported data on drinking behavior and experiences related to alcohol collected 10-15 years after surgery.

RESULTS

Out of the 959 patients undergoing RYGB in the period, 29 were diseased and 546 participated in this follow-up study (58.7%). Focusing on suspicious changes in drinking behavior, 8.8% reported drinking more, 11.5% consumed alcohol at least twice a week, and 10.6% consumed at a minimum of 6 units of alcohol at a frequency of at least once monthly. The nature of hangovers had changed for about a third of the patients, with 21.6% reporting these to feel weaker or absent. Repeated alcoholic blackouts were reported by 11.9%. A subgroup of the patients were categorized as displaying presumed problematic drinking behavior(PPDB). Among the PPDB-men there was a significant association to having had a fall last year (6 (100.0%) PPDB-patients vs. 30 (29.7%) non-PPDB, p<.001). Among the PPDB-women, there was a significant association to having had alcohol problems prior to surgery (7 (70.0%) PPDB-patients vs. 67 (17.7%) non-PPDB, p<.001). Less significant associations to PPDB reported for explorative purposes were lack of patient education (men) (16 (26.2%) PPDB-patients vs. 8 (61.5%) non-PPDB, p=.014); more than 3 months persistent musculoskeletal pain (women) (45 (15.3%) PPDB-patients vs. 29 (24.6%) non-PPDB, p=.026); subjective problems with memory (women) (58 (20.7%) PPDB-patients vs. 10 (9.1%) non-PPDB, p=.006); and, receiving professional help for mental problems last 12 months (women) (29 (22.7%) PPDB-patients vs. 45 (14.7%) non-PPDB, p=.043).

CONCLUSION

A subset of patients display drinking behaviors that may be consistent with postsurgical alcohol problems. Screening instruments like AUDIT may not be sufficiently specific to capture several risk behaviors occurring after bariatric surgery.