Long-term dietary intake and nutritional deficiencies following sleeve gastrectomy or Roux-En-Y gastric bypass in a mediterranean population

Short-term impact of bariatric surgery on the dietary intake of patients with type 2 diabetes

BACKGROUND

The prevalence of overweight and obesity and an unhealthy diet and lifestyle are the key causes of rising diabetes burden in India. Bariatric surgery is gaining popularity in India as a favored approach to manage obesity and its accompanying comorbidities. Despite this, there is a scarcity of Indian studies evaluating dietary intake. Our goal was to analyse the dietary intake of Indian patients with type 2 diabetes mellitus (T2DM) who have undergone laparoscopic sleeve gastrectomy (LSG) or duodeno-jejunal bypass with sleeve gastrectomy (DJB-SG) or surgeries.

METHODS

The longitudinal observational study included 64 T2DM patients (32 in each procedure) enrolled through purposive sampling. The patients underwent surgery (LSG or DJB-SG procedure) between January 2017 and July 2019. Dietary data was collected at baseline and postsurgery (12 months) using a 24-h dietary recall method for 2 days (one working and one holiday).

RESULTS

The total sample consisted of 27 (42.2%) females and 37 (57.8%) males. The mean age was 46.8 years. At 12 months, the follow-up for the LSG and DJB-SG procedures was 100% and 78%, respectively. In the short term, a significant reduction was seen in weight, body mass index and haemoglobin A1C (HbA1C) in both surgical groups. The two procedures were comparable with respect to weight loss but improvement in glycaemia was higher in the DJB-SG group. The dietary intake (food groups and nutrients) was similar in the two surgical groups at baseline and 12 months postsurgery. Dietary intake assessment showed significant reduction in calorie dense foods (cereals, roots and tubers, fats and oils, table sugar, and biscuits) in both surgical groups. Among nutrients, intake of energy, fats, carbohydrates, dietary fibre, thiamine, riboflavin, niacin, folate and iron were reduced significantly in both procedures. Vitamin D (84.4% patients in LSG group and 81.3% patients in DJB-SG) and iron (62.5% patients in LSG group and 68.8% patients in DJB-SG) were commonly prevalent nutritional deficiencies at baseline and were significantly reduced at 12 months.

CONCLUSIONS

In the short term, bariatric surgery resulted in weight loss and improvement in glycaemia. Bariatric surgery does significantly affect dietary intake leading to nutritional deficiencies. Therefore, patients should be recommended vitamin and mineral supplements and regular patient education and counselling by a trained bariatric dietitian to prevent nutritional deficiencies and maintain nutritional status.

Iron Treatment in Patients with Iron Deficiency Before and After Metabolic and Bariatric Surgery: A Narrative Review

Iron is an essential nutrient in living organisms with multiple vital functions. Iron deficiency (ID) can cause long term health consequences beyond iron deficiency anemia (IDA). The high prevalence of ID and its long-term effects in patients with obesity and after metabolic and bariatric surgery (MBS) is recognized. Nevertheless, there is limited knowledge of the optimal route or dose for treatment of patients with obesity and post-MBS, and an evidence-based universal guideline for prevention and treatment of ID in short- and long-term post-MBS (PMBS) is not yet available. ID in the general population is currently treated with oral or parenteral iron, where oral iron treatment is considered the preferred option with parenteral iron as a second-line treatment in case there is intolerance or lack of response to oral iron. In patients with obesity with chronic low-grade inflammation and PMBS patients with altered gut anatomy and function, there are also alterations in the bioavailability and higher risks of side effects of available oral irons. The conclusions of current studies exploring effective treatment of iron deficiency in this population have been inconsistent and further well-planned randomized and prospective studies are needed. This is a narrative review of the literature on the available treatment options and strategies for treatment of ID in PMBS patients to recognize the knowledge gaps and provides topics of future research.

Metabolic and Bariatric Surgery for Adolescents

Obesity is a chronic, complex, and multifactorial disease. Currently, approximately 6% have severe obesity with higher rates seen among racial/ethnic minority subgroups and in rural communities. Severe obesity is associated with cardiometabolic, psychologic, and musculoskeletal comorbidities. Metabolic and bariatric surgery is an effective treatment option for adolescents endorsed by major pediatric organizations. The most common procedure is the vertical sleeve gastrectomy. Pre-operative evaluation includes an in-depth medical, nutrition, physical activity and psychosocial assessment, with a care plan developed by a multidicplinary team with the adolescent and caregiver. The post-operative plan should include monitoring for surgical complications, weight regain, micronutrient deficiencies, psychologic challenges, and transition to adult care.

Show me the evidence to guide nutrition practice: Scoping review of macronutrient dietary treatments after metabolic and bariatric surgery

BACKGROUND

Clinical practice recommendations for macronutrient intake in Metabolic and Bariatric Surgery (MBS) are insufficiently grounded in the research, possibly due to a paucity of research in key areas necessary to support macronutrient recommendations. An initial scoping review, prior to any systematic review, was determined to be vital.

OBJECTIVES

To identify topical areas in macronutrients and MBS with a sufficient evidence base to guide nutrition recommendations.

METHODS

PubMed, Cochrane, Ovid Medline, and Embase were initially searched in January 2019 (updated November 1, 2023) with terms encompassing current bariatric surgeries and macronutrients. Out of 757 records identified, 98 were included. A template was created. Five types of outcomes were identified for extraction: dietary intake, anthropometrics, adverse symptoms, health, and metabolic outcomes. All stages of screening and extraction were conducted independently by at least two authors and disagreements were resolved via team discussion. Macronutrient-related dietary treatments were classified as either innovative or standard of care. Descriptions of dietary arms were extracted in detail for a qualitatively generated typology of dietary or nutritional treatments. Heatmaps (treatments by outcomes) were produced to identify promising topics for further systematic analyses.

RESULTS

We identified protein supplementation and "food-focused" (e.g., portion-controlled meals, particular foods in the diet, etc.) topical areas in MBS nutrition care with potentially sufficient evidence to create specific MBS Macronutrients guidelines and identified topical areas with little research.

CONCLUSIONS

Clinical practice regarding macronutrient intake remains guided by consensus and indirect evidence. We detail ways that leadership at the profession level may remedy this.

Nutritional Challenges and Treatment After Bariatric Surgery

Bariatric surgery is an important weight loss tool in individuals with severe obesity. It is currently the most effective long-term weight loss treatment that lowers obesity-related comorbidities. It also has significant physiological and nutritional consequences that can result in gastrointestinal complications and micronutrient deficiencies. After gastric bypass, clinical events that negatively affect nutritional status include malabsorption, dumping syndrome, kidney stones, altered intestinal bile acid availability, bowel obstruction, ulcers, gastroesophageal reflux, and bacterial overgrowth. Risk factors for poor nutritional status and excessive loss of lean body mass and bone include reduced dietary quality and inadequate intake, altered nutrient absorption, and poor patient compliance with nutrient supplementation. There are unique concerns in adolescents, older individuals, and individuals who become pregnant postoperatively. With careful management, health-care professionals can assist with long-term weight loss success and minimize the risk of acute and long-term nutrition complications after bariatric surgery.

The Role of Dietary Intake in the Weight Loss Outcomes of Roux-en-Y Gastric Bypass and Sleeve Gastrectomy: A Systematic Review and Meta-analysis

The relationship between postoperative dietary intake and weight loss after bariatric surgery remains unclear. We performed a systematic review and meta-analysis of studies published between January 2000 and May 2023, reporting weight loss outcomes, and dietary intake before and after Roux-en-Y gastric bypass and sleeve gastrectomy. A total of 42 studies were included. There was no detectable difference in dietary intake between the two procedures. Roux-en-Y gastric bypass induced an average decrease in energy intake of 886 kcal/day at 12-month post-surgery; however, there was no correlation between daily energy intake and weight loss. These findings show a substantial reduction of energy intake in the first year after bariatric surgery but do not support a link between lower energy intake and greater weight loss.

Long-term prevalence of vitamin deficiencies after bariatric surgery: a meta-analysis

BACKGROUND

Bariatric surgery can lead to short-mid-term vitamin deficiencies, but the long-term vitamin deficiencies is unclear. This study aimed to conduct a meta-analysis regarding the long-term prevalence (≥ 5 years) of vitamin deficiencies after bariatric surgery.

METHODS

We searched the EMBASE, PubMed, and CENTRAL databases for clinical studies until June 2023. Meta-analysis, sensitivity, subgroup, and meta-regression analyses were performed.

RESULTS

This meta-analysis included 54 articles with follow-up duration ranging from 5 to 17 years. The most prevalent vitamin deficiencies after surgery were vitamin D (35.8%), followed by vitamin E (16.5%), vitamin A (13.4%), vitamin K (9.6%), and vitamin B12 (8.5%). Subgroup analyses showed that the prevalence of vitamin A and folate deficiencies increased with the follow-up time. Roux-en-Y gastric bypass had a higher rate of vitamin B12 deficiency than sleeve gastrectomy and biliopancreatic diversion with duodenal switch (BPD-DS). Studies conducted in Europe had higher vitamin A deficiency (25.8%) than in America (0.8%); Asian studies had more vitamin B12 but less vitamin D deficiency than European and American studies. Meta-regression analysis displayed that publication year, study design, preoperative age, BMI, and quality assessment score were not associated with vitamin A, B12, D, and folate deficiencies rate.

CONCLUSION

A high prevalence of vitamin deficiencies was found after bariatric surgery in the long-term follow-up, especially vitamin D, E, A, K, and B12. The variation in study regions, surgical procedures, and follow-up time are associated with different postoperative vitamin deficiencies; it is necessary to develop more targeted vitamin supplement programs.

Assessing Nutritional Deficiencies in Bariatric Surgery Patients: A Comparative Study of Roux-en-Y Gastric Bypass versus Sleeve Gastrectomy

Obesity is a worldwide epidemic, and bariatric surgery is considered the primary treatment for long-term weight loss and managing obesity-related health issues. Sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) are the most performed procedures. Nutritional deficiencies are a significant concern following bariatric surgery and can have serious consequences. This study aims to compare the incidence of nutritional deficiencies in patients undergoing RYGB and SG. A retrospective analysis was conducted on the nutritional status of 505 consecutive patients who underwent either RYGB or SG between January and December 2019. Data were collected regarding vitamin B12, folic acid, vitamin D, calcium, PTH, magnesium, hemoglobin, iron, ferritin, and transferrin at preoperative, 6-month, and 12-month intervals post-surgery. The RYGB group showed significantly higher excess weight loss. Vitamin B12, hemoglobin, and ferritin levels were consistently higher in the SG group throughout the study. Vitamin D deficiency was prevalent, with no significant difference between the groups. Vitamin B12 deficiency was significantly more common in the RYGB group (6 months: 17.46% vs. 4.69%, p < 0.001; 12 months: 16.74% vs. 0.93%, p < 0.001). Despite differences in their mechanisms, bariatric surgeries were associated with nutritional deficiencies. It is crucial to efficiently assess, prevent, and manage these deficiencies tailored to each surgical procedure.

A Comparison of the Health Benefits of Customized Multivitamins and Standard Supplementation Post-bariatric Surgery: A Systematic Review

Rates of obesity increase worldwide year after year. This review explored if customized multivitamins (CMV) resulted in less micronutrient deficiency and higher serum levels of vitamins and minerals when compared to standard multivitamins (SMV) post-bariatric surgery in adults. Vitamins investigated were vitamins B1, B6, B12, D, parathyroid hormone (PTH), calcium, iron, hemoglobin, ferritin, folic acid, zinc, and magnesium. In Roux-en-Y gastric bypass (RYGB) patients weight loss surgeries (WLS) Forte or chewable CMV were studied, while in sleeve gastrectomy (SG) patients, WLS Optimum 1.0 (Opt. 1.0) or WLS Optimum 2.0 (Opt. 2.0) multivitamins were studied. An electronic search was performed on three databases (PubMed (n=28), Embase (n=120), and Cochrane (n=106)) to identify clinical trials and cohort studies. The inclusion criteria focused on studies since 2011 for adults ≥18 years old post-GB and SG. The keywords included bypass, sleeve, WLS, and multivitamins. Four clinical trials and three cohort studies were included. Jadad Scale was used to assess the quality and the bias risk in the clinical trials and the Newcastle-Ottawa scale (NOS) was used for the cohort studies. The PICO model and PRISMA rules were followed, where the outcomes targeted certain vitamin serum levels and the levels of deficiencies. The results of WLS Forte were better than SMV. The chewable CMV and Opt. 1.0 results were comparable to SMV. Opt. 2.0 was slightly better than Opt. 1.0. Further modifications would enhance the CMV presented in this systemic review. SMV would still be recommended until CMV are modified and tested. Multi-center trials that monitor the effect of the modified CMV on the serum levels of vitamins and minerals in the longer term in different wider populations are needed.

Effect of sleeve gastrectomy on the levels of oral volatile sulfur compounds and halitosis-related bacteria

Background

The association between sleeve gastrectomy and halitosis remains relatively unknown. Therefore, this study aimed to evaluate the effect of sleeve gastrectomy on halitosis and the oral bacterial species associated with halitosis in patients with obesity.

Methods

This was a prospective longitudinal cohort study that examined patients before and after sleeve gastrectomy and followed the patients at three time intervals (1, 3, and 6 months) after sleeve gastrectomy. Clinical periodontal measurements (plaque index [PI], gingival index [GI], and probing depth [PD]) were obtained. In addition, plaque samples were collected for quantification of the periodontopathogenic bacteria: Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Fusobacterium nucleatum using real-time quantitative polymerase chain reaction (qPCR). In addition, breath samples were collected to analyze the concentration of volatile sulfur compounds (VSCs), namely hydrogen sulfide (H2S), methyl mercaptan (CH3SH), and dimethyl sulfide (CH3SCH3), via portable gas chromatography (Oral Chroma™).

Results

Of the 43 patients initially included, 39 completed the study, with a mean age of 32.2 ± 10.4 years. For PI and GI repeated measurements one way analysis of variance showed a significant increase (p-value < 0.001 for both) one month after surgery, with mean values of 1.3 and 1.59, respectively, compared to the baseline. During the same period, the number of P. gingivalis increased, with a p-value = 0.04. Similarly, the levels of hydrogen sulfide (H2S) and methyl mercaptan (CH3SH) increased significantly in the first month after surgery (p-value = 0.02 and 0.01, respectively).

Conclusion

This study demonstrated that sleeve gastrectomy may lead to increased halitosis one month post-surgery, attributed to elevated and P. gingivalis counts, contributing to the development of gingivitis in obese patients who underwent sleeve gastrectomy. This emphasizes the importance of including oral health professionals in the multidisciplinary team for the management of patients undergoing bariatric surgery.

Micronutrient status 2 years after bariatric surgery: a prospective nutritional assessment

Background

Among commonly performed bariatric surgeries, biliopancreatic diversion with duodenal switch (BPD-DS) provides greater weight loss than Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG), with sustained metabolic improvements. However, the risk of long-term nutritional deficiencies due to the hypoabsorptive component of BPD-DS hinders its widespread use.

Objective

The aim of the study was to examine nutritional status over 2 years after BPD-DS, RYGB or SG.

Methods

Patients were recruited in the REMISSION trial (NCT02390973), a single-center, prospective study. Out of 215 patients, 73, 48 and 94, respectively, underwent BPD-DS, RYGB or SG. Weight loss, micronutrient serum levels (including iron, calcium, parathormone, vitamins A, B12 and D), and nutritional supplementation were assessed over 2 years. Patients were supplemented according to the type of surgery and individual micronutrient level evolution.

Results

At baseline, BPD-DS patients were younger than SG patients (p = 0.0051) and RYGB patients had lower body mass index (p < 0.001). Groups had similar micronutrient levels before surgery, with vitamin D insufficiency as the most prevalent nutritional problem (SG: 38.3%, RYGB: 39.9%, BPD-DS: 54.8%, p = 0.08). BPD-DS patients showed lower levels of iron, calcium and vitamin A than SG patients at 24 months. Groups had similar levels of vitamin D at 24 months. Prevalence of vitamin D, calcium, iron, vitamin A and vitamin B12 deficiency was similar among groups at 24 months. Rates of vitamin D insufficiency and iron deficiency were lower at 24 months than at baseline. Micronutrient intake was consistent with recommendations in groups post-surgery, but most BPD-DS patients took vitamin A and vitamin D supplement doses above initial recommendations.

Conclusion

With appropriate medical and nutritional management, all surgeries led to similar rates of vitamin D, calcium, iron, vitamin A and vitamin B12 deficiencies at 24 months. However, initial vitamin A and vitamin D supplementation recommendations for BPD-DS patients should be revised upwards.

Mental Health, and Eating Disorders in Patients After Roux-en-Y Gastric Bypass Surgery (RYGB)

<b>Introduction:</b> Obesity, as one of the main health problems worldwide, is associated with an increased risk of developing mental and eating disorders and negative eating habits. Bariatric surgery allows for rapid weight loss and alleviates the symptoms of concomitant diseases in obese patients.<b>Aim:</b> Pre- and postoperative estimation of mental disorders and eating behaviors in patients after Roux-en-Y Gastric Bypass (RYGB).<b>Material and methods:</b> Analysis of data from up to 5 years of follow-up including clinical examination and questionnaires.<b>Results:</b> Following parameters decreased after RYGB: anxiety and hyperactivity from 32.81% to 21.88%, mood disorders - 31.25% to 20.31%, substance abuse - 40.63% to 28.13%, emotional eating - 76.56% to 29.69%, binge eating - 50% to 6.25%, night eating - 87.5% to 20.31%. Postoperative rates of: negative eating habits, daily intake of calories and sweetened beverages, flatulence, constipation, and abdominal pain decreased, while the rate of food intolerance and emesis increased.<b>Conclusions:</b> In our patients, the occurrence of: mental and eating disorders, negative eating habits, daily calories, sweetened beverages, coffee intake decreased after weight loss (as a result of RYGB), but water, vegetables and fruit consumption increased. Lower rate of flatulence, constipation, and abdominal pain, but higher of food intolerance and emesis were also confirmed after RYGB.

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.

The Effects of Sleeve Gastrectomy on the Appetitive Domain of Taste Using the Progressive Ratio Task

INTRODUCTION

Sleeve gastrectomy (SG) is an effective treatment for obesity in adolescents. The underlying weight loss mechanism may impact the peripheral and central gustatory system along with reward circuits in the brain. This study aims to assess changes in appetitive behavior in short-, medium-, and long-term follow-up.

METHODS

In this prospective observational study, a total of 8 adolescents with obesity who underwent SG and 9 comparator unoperated participants were studied. Appetitive behaviour towards fat and sweet taste stimuli was assessed using the Progressive Ratio Task (PRT) over a 6 year period.

RESULTS

Mean body mass index (BMI) of the surgical patients dropped from 51.5 ± 2.8 kg/m2 to 31.4 ± 1.9 and 30.9 ± 2.3 kg/m2 at 1 and 6 years follow-up, respectively. (p < 0.001). The median (interquartile range) total rewards earned during the PRT was 6 (5-7) pre-surgery, 5 (3-6) after one year and 4 (2-4) after six years from surgery (p = 0.007).

CONCLUSION

SG reduced appetitive behaviour at 1 year with maintained the benefit over 6 years as measured by the progressive ratio task.

Association of postoperative dietary macronutrient content and quality with total weight loss and fat-free mass loss at midterm after sleeve gastrectomy

OBJECTIVES

This study aimed to investigate the associations of macronutrient quantities and qualities with percentage total weight loss and percentage of fat-free mass loss relative to total weight loss in adults undergoing sleeve gastrectomy.

METHODS

This cross-sectional study included 146 patients on postoperative time since sleeve gastrectomy of 2 to 4 y. Diet was assessed using a food frequency questionnaire. Macronutrient quality index, carbohydrate quality index, fat quality index, and healthy plate protein quality index were calculated. The associations of dietary variables with percentage total weight loss and percentage of fat-free mass loss relative to total weight loss were determined using linear regression. Logistic regression was used to estimate the odds of non-response (percentage total weight loss < 25%) and excessive fat-free mass loss (percentage of fat-free mass loss relative to total weight loss > 28%) based on dietary intakes.

RESULTS

Forty-six (31.5%) were non-responders, and 49 (33.6%) experienced excessive fat-free mass loss. The fully adjusted model showed a 0.75 decrease in percentage total weight loss per 5% carbohydrate increase (95% CI, -1.45 to -0.05). The odds of non-response were 53% lower per 5% increase in protein (95% CI, 0.23-0.94). Each 5-g higher intake of fat was associated with 0.29 higher percentage of fat-free mass loss relative to total weight loss (95% CI, 0.03-0.55). The odds of excessive fat-free mass loss were reduced by 5% per gram of fiber intake (95% CI, 0.90-0.99). Each 5% increment in energy intake from protein that was isocalorically substituted for either carbohydrate or fat was associated with lower odds of nonresponse. Macronutrient quality indices had no significant associations.

CONCLUSIONS

Adherence to a high-protein, high-fiber diet after sleeve gastrectomy may enhance surgical success by improving total weight loss and preventing excessive fat-free mass loss.

Impact of bariatric surgery on ovarian reserve markers and its correlation with nutritional parameters and adipokines

Introduction

A reduction in anti-müllerian hormone (AMH) levels at short-term after bariatric surgery (BS) has been previously described. However, an assessment of ovarian reserve at longer-follow up, and a comprehensive evaluation of the potentially implicated factors has not been reported.

Design

Prospective cohort study.

Materials and methods

Twenty women aged 18-40 years with BMI 43.95 kg/m2 undergoing BS were studied at baseline (BS0), and at 1 month (BS1), 4 months (BS2), 12 months (BS3), and 24-36 months (BS4) after the surgery. Anthropometrics, reproductive hormones (AMH, FSH, LH, estradiol, testosterone, SHBG, androstenedione), metabolic parameters (adiponectin, leptin, ghrelin, insulin), and nutritional blood parameters (markers of nutritional status, vitamins, and minerals) were obtained at each study time point. Antral follicular count (AFC) was assessed by ultrasonography at BS0, BS3, and BS4. Mixed models were used for analysis of longitudinal data.

Results

The mean AMH level was 3.88 ng/mL at BS0, decreased at BS3 (mean= 2.59 ng/mL; p=0.009), and remained stable between BS3 and BS4 (mean= 2.96 ng/mL; p=0.409). We also observed a non-significant decrease in AFC at BS3 (mean=26.14 at BS0, mean 16.81 at BS3; p=0.088) that remained stable at BS4 (mean= 17.86; p=0.731). Mixed models analysis showed: (a) a decrease in 10 kg of body weight was associated with an average decrease of 0.357 ng/mL in AMH (p=0.014); (b) a decrease in 1 BMI point was associated with an average decrease of 0.109 ng/mL in AMH (p=0.005); (c) an increase in 1 µg/mL of adiponectin was associated with an average decrease of 0.091 ng/ml in AMH (p=0.041) Significant positive correlations were found between the AMH levels after BS and plasma concentrations of testosterone, free androgen index, insulin and HOMA index. No significant correlations were detected between AMH levels and nutritional parameters.

Conclusions

Our results were in line with previous observations, showing that AMH levels decreased significantly at 12 months after bariatric surgery, in parallel with a non-significant reduction in AFC. Both ovarian reserve markers showed a later stabilization up to the end of the study. Of note, postoperative AMH levels were positively correlated with key androgen and insulin resistance-related parameters.

Pre- and Post-surgical Prevalence of Thiamine Deficiency in Patients Undergoing Bariatric Surgery: a Systematic Review and Meta-analysis

Thiamine deficiency is a life-threatening nutritional abnormality observed in the patients with obesity and following bariatric surgery. The aim of the present study is to determine the prevalence of thiamine deficiency prior to and after bariatric procedures. PubMed, Web of Science, Google scholar, CENTRAL, ProQuest, and Scopus were searched to retrieve relevant studies containing data on thiamine deficiency in patients with obesity who underwent bariatric surgery. A proportional meta-analysis approach was used to pool the prevalence of thiamine deficiency prior and after surgery. Our comprehensive literature search retrieved 41 studies with relevant data. The pooled prevalence of thiamine deficiency was 7% (95% CI: 4-12%) at baseline. We observed that 19% (95% CI: 0-68%), 9% (95% CI: 3-17%), and 6% (95% CI: 3-9%) of patients had developed thiamine deficiency at 3 months, 6 months, and 1 year after surgery, respectively. We also report that the prevalence of thiamine deficiency in pregnant women who had history of bariatric surgery. The rate was highest in the first trimester (12%) compared to that in the second (8%) and third (10%) trimesters. The baseline prevalence is 7% for thiamine deficiency in bariatric surgery candidates. The prevalence rate of thiamin deficiency increased to 19% and 9% 3 and 6 months after surgery; however, the rate decreased to 6% 1 year after surgery. Due to the higher prevalence of thiamine deficiency in the early post-operative phase, close monitoring during this period is recommended. A similar strategy should be implemented for pregnant women with history of bariatric surgery in their first trimester.

Obesity surgery and neural correlates of human eating behaviour: A systematic review of functional MRI studies

Changes in eating behaviour including reductions in appetite and food intake, and healthier food cue reactivity, reward, hedonics and potentially also preference, contribute to weight loss and its health benefits after obesity surgery. Functional magnetic resonance imaging (fMRI) has been increasingly used to interrogate the neural correlates of eating behaviour in obesity, including brain reward-cognitive systems, changes after obesity surgery, and links with alterations in the gut-hormone-brain axis. Neural responses to food cues can be measured by changes in blood oxygen level dependent (BOLD) signal in brain regions involved in reward processing, including caudate, putamen, nucleus accumbens, insula, amygdala, orbitofrontal cortex, and top-down inhibitory control, including dorsolateral prefrontal cortex (dlPFC). This systematic review aimed to examine: (i) results of human fMRI studies involving obesity surgery, (ii) important methodological differences in study design across studies, and (iii) correlations and associations of fMRI findings with clinical outcomes, other eating behaviour measures and mechanistic measures. Of 741 articles identified, 23 were eligible for inclusion: 16 (69.6%) longitudinal, two (8.7%) predictive, and five (21.7%) cross-sectional studies. Seventeen studies (77.3%) included patients having Roux-en-Y gastric bypass (RYGB) surgery, six (26.1%) vertical sleeve gastrectomy (VSG), and five (21.7%) laparoscopic adjustable gastric banding (LAGB). The majority of studies (86.0%) were identified as having a very low risk of bias, though only six (27.3%) were controlled interventional studies, with none including randomisation to surgical and control interventions. The remaining studies (14.0%) had a low risk of bias driven by their control groups not having an active treatment. After RYGB surgery, food cue reactivity often decreased or was unchanged in brain reward systems, and there were inconsistent findings as to whether reductions in food cue reactivity was greater for high-energy than low-energy foods. There was minimal evidence from studies of VSG and LAGB surgeries for changes in food cue reactivity in brain reward systems, though effects of VSG surgery on food cue reactivity in the dlPFC were more consistently found. There was consistent evidence for post-operative increases in satiety gut hormones glucagon-like-peptide 1 (GLP-1) and peptide YY (PYY) mediating reduced food cue reactivity after RYGB surgery, including two interventional studies. Methodological heterogeneity across studies, including nutritional state, nature of food cues, post-operative timing, lack of control groups for order effects and weight loss or dietary/psychological advice, and often small sample sizes, limited the conclusions that could be drawn, especially for correlational analyses with clinical outcomes, other eating behaviour measures and potential mediators. This systematic review provides a detailed data resource for those performing or analysing fMRI studies of obesity surgery and makes suggestions to help improve reporting and design of such studies, as well as future directions.

Effects of medical and surgical treatment on vitamin D levels in obesity

INTRODUCTION

Persons living with obesity treated with bariatric surgery are at a high risk of developing nutritional deficiencies. The primary aim of this observational cohort study was to compare vitamin D levels in patients two years after bariatric surgery (Roux-en-Y gastric bypass/RYGB and sleeve gastrectomy/SG) with a very low-energy diet (VLED). The same subjects were also compared with a population sample from the same region at baseline. The primary hypothesis was that surgery, especially RYGB, would lead to an increased prevalence of vitamin D deficiency compared to subjects treated with VLED. 971 individuals eligible for surgical, RYGB (n = 388), SG (n = 201), and medical treatment (n = 382), in routine care, were included consecutively between 2015 and 2017. A random population sample from the WHO-MONICA project was used as a reference, (n = 414). S-calcium, S-25(OH)D (vitamin D), and S-PTH (parathyroid hormone) were measured in all persons with obesity at baseline and two years after treatment (n = 713). Self-reported use of vitamin D and calcium supplementation was registered.

RESULTS

Vitamin D deficiency (S-25(OH)D <25mmol/l) was found in 5.2% of the persons with obesity at baseline versus 1.7% of the general population (SMD>0.1). S-25(OH)D increased for all treatment groups but was higher in RYGB and SG (SMD>0.1, standardized mean difference). Thirteen subjects (1.8%) had vitamin D deficiency after obesity treatment.

CONCLUSION

Surgical intervention for obesity followed by vitamin D supplementation was not associated with a higher risk for vitamin D deficiency, irrespective of surgery type, compared to individuals on medical treatment. However, persons living with obesity seeking weight loss treatment are more likely to have deficient vitamin D levels compared to the general population.

Development and complications of nutritional deficiencies after bariatric surgery

The clinical effectiveness of bariatric surgery has encouraged the use of bariatric procedures for the treatment of morbid obesity and its comorbidities, with sleeve gastrectomy and Roux-en-Y gastric bypass being the most common procedures. Notwithstanding its success, bariatric procedures are recognised to predispose the development of nutritional deficiencies. A framework is proposed that provides clarity regarding the immediate role of diet, the gastrointestinal tract and the medical state of the patient in the development of nutritional deficiencies after bariatric surgery, while highlighting different enabling resources that may contribute. Untreated, these nutritional deficiencies can progress in the short term into haematological, muscular and neurological complications and in the long term into skeletal complications. In this review, we explore the development of nutritional deficiencies after bariatric surgery through a newly developed conceptual framework. An in-depth understanding will enable the optimisation of the post-operative follow-up, including detecting clinical signs of complications, screening for laboratory abnormalities and treating nutritional deficiencies.

Prevalence and associated factors of vitamin D deficiency after Roux-en-Y gastric bypass: a systematic review and meta-analysis

OBJECTS

To estimate the prevalence and associated factors of vitamin D deficiency (VDD) after Roux-en-Y gastric bypass (RYGB).

METHODS

PubMed, EMBASE, and CENTRAL were searched for relevant records from inception to 17 March 2023, using search terms: vitamin D, vitamin D3, vitamin D deficiency, hypovitaminosis D, gastric bypass, and RYGB. Studies were eligible for inclusion if they provided related data on VDD prevalence after RYGB.

RESULTS

Of the 1119 screened studies, 72 studies involving 7688 individuals were enrolled in the final analysis. The prevalence estimates of VDD after RYGB were 42%. Subgroup analyses suggested the pooled prevalence of postoperative VDD was 35% for follow-up duration less than or equal to 1 year, 43% for greater than 1 and less than or equal to 5 years, and 54% for greater than 5 years. Meta-regression showed that VDD prevalence was positively correlated with follow-up time. Also, the prevalence was higher in studies with inadequate vitamin D supplementation than in those with adequate supplementation and in Asia population than in those from South America, Europe, and North America. Other factors associated with high VDD prevalence after RYGB included high presurgical VDD prevalence, noncompliant patients, and black populations. No significant association existed between VDD and alimentary length.

CONCLUSION

VDD presented a high prevalence in patients following RYGB. It occurred more frequently with longer postoperative follow-up time. Population-specific vitamin D supplementation measures, targeted treatment for presurgical VDD, improved patient compliance, and periodical follow-ups were necessary to reduce VDD and other adverse outcomes.

Comparative analysis of lifestyle behaviors and dietary intake among obese and non-obese individuals following bariatric surgery: a secondary data analysis from 2020 to 2022

Objective

The aim of this research is to perform a comparative examination of lifestyle habits and dietary consumption between obese and non-obese subjects who have undergone bariatric surgery. This is done with the intent of investigating the disparities in obesity outcomes attributable to these elements.

Method

This study involves a secondary analysis of cross-sectional data obtained from the Sharik Diet and Health National Survey (SDHNS). To ensure a representative distribution of participants, the SDHNS employs a proportional quota sampling strategy, with stratification based on age, sex, and geographic location within Saudi Arabia's 13 administrative regions, utilizing the ZDataCloud® system for this purpose. The data, collected between 2020 and 2022 from over 15,000 participants, were screened to identify the eligible records of individuals who underwent bariatric surgery.

Results

Within the entire sample, a mere 5.0% (806 individuals) had undertook bariatric surgery, with females comprising 54% of this specific subgroup. The average age within this group was 38.85 years (SD 13.02) and range (18-87). Post-operative results showed that 33% of these individuals remained classified as obese. Utilizing the backward likelihood ratio regression model, it was determined that factors including age, decreased consumption of fresh juices and chicken, as well as current tobacco use, were significantly associated with persistent obesity.

Conclusion

The findings of this study suggest an association between the non-obese group and healthier lifestyle choices, including the consumption of high-protein diets and fresh juices, alongside a decreased prevalence of smoking. These observations underscore the significance of maintaining a healthy lifestyle for positive weight loss outcomes following bariatric surgery.

A Systematic Review and Meta-Analysis of Vitamin D Status of Patients with Severe Obesity in Various Regions Worldwide

INTRODUCTION

Managing nutritional deficiencies is an essential component in the treatment of severe obesity. Vitamin D deficiency is often reported in investigations in severely obese cohorts. However, no prior study has summarized findings on this topic. Consequently, the aim of this systematic review and meta-analysis was to investigate the 25-hydroxyvitamin D [25(OH)D] status in individuals with severe obesity in different regions worldwide. We also evaluated levels of calcium, parathyroid hormone (PTH), and magnesium as secondary outcome measures.

METHODS

We searched Medline, PubMed, Scopus, the Cochrane Library, and EMBASE for relevant observational studies published in English from 2009 to October 2021. The heterogeneity index among the studies was determined using the Cochran (Q) and I2 tests. Based on the heterogeneity results, the random-effect model was applied to estimate the prevalence of vitamin D deficiency.

RESULTS

We identified 109 eligible observational studies. Overall, 59.44% of patients had vitamin D deficiency [25(OH)D <20 ng/mL], whereas 26.95% had vitamin D insufficiency [25(OH)D 20-30 ng/mL]. Moreover, the mean 25(OH)D level was 18.65 ng/mL in 96 studies. The pooled mean estimate of the serum calcium, PTH, and magnesium was 9.26 mg/dL (95% confidence interval [CI]: 9.19-9.32, I2 = 99.7%, p < 0.001), 59.24 pg/mL (95% CI: 54.98, 63.51, I2 = 99.7%, p < 0.001), and 0.91 mg/dL (95% CI: 0.84, 0.98, I2 = 100.0%, p < 0.001), respectively. The results of the subgroup analysis indicated that the mean estimates of 25(OH)D were highest in North America (21.71 ng/mL [19.69, 23.74], [I2 = 97.2%, p < 0.001]) and lowest in Southeast Asia (14.93 ng/mL [14.54, 15.33], [I2 = 0.0%, p = 0.778]).

CONCLUSION

The results obtained showed a significant prevalence of vitamin D deficiency among severely obese individuals in various geographical regions, whereas the highest and lowest mean estimates were reported for North America and Southeast Asia, respectively.

VITAMIN D LEVELS AND LIPID PROFILE IN PATIENTS UNDERGOING BARIATRIC SURGERY

BACKGROUND

Vitamin, mineral, and metabolic deficiencies occur in the postoperative period of bariatric surgery, in the short and long term, and are worrisome intercurrences.

AIMS

To evaluate the association of serum vitamin D levels with the lipid profile in obese patients undergoing bariatric surgery.

METHODS

Case series of patients assisted from 2010 to 2018, in a private hospital of medium and high complexity, who underwent bariatric surgery using sleeve gastrectomy or Roux-en-Y gastric bypass techniques, monitored by the same surgeon. Sociodemographic, clinical, laboratory, and anthropometric data were collected preoperatively and at 6, 12, and 24 months after surgery.

RESULTS

A total of 156 individuals, mostly female (75.6%) were monitored. The most frequent comorbidities were hepatic steatosis (76.3%) and hypertension (48.27). Regarding preoperative vitamin D levels, only 18.9% of the population had a satisfactory level (≥30 ng/mL). There was a reduction in weight and an improvement in the lipid profile after surgery. Significant correlations were observed between the lipid profile and vitamin D concentration only in the sample submitted to the Roux-en-Y gastric bypass technique: negative correlation between total cholesterol and vitamin D two years after surgery; positive correlation between triglycerides and vitamin D one year after surgery; and negative correlation between high-density lipoprotein and vitamin D two years post-surgery.

CONCLUSIONS

It is essential to routinely monitor vitamin D levels and lipid profile pre- and postoperatively in order to avoid damage associated with this vitamin deficiency.

Dietary Macronutrient Composition and Quality, Diet Quality, and Eating Behaviors at Different Times Since Laparoscopic Sleeve Gastrectomy

PURPOSE

This study aimed to compare energy, macronutrients (quantity and quality), the overall dietary quality, and eating behaviors of patients undergoing laparoscopic sleeve gastrectomy (LSG) at different times since surgery.

MATERIALS AND METHODS

This cross-sectional study included 184 adults at least 1 year post-LSG. Dietary intakes were assessed by a 147-item food frequency questionnaire. Macronutrient quality was assessed by computing the macronutrient quality index (MQI), carbohydrate quality index, fat quality index, and healthy plate protein quality index (HPPQI). The Healthy Eating Index (HEI)-2015 was used to assess diet quality. The Dutch Eating Behavior Questionnaire was used to assess eating behaviors. Based on the time since LSG, the time at which eating data were also collected, participants were categorized into three groups: 1-2 years (group 1), 2-3 years (group 2), and 3-5 years (group 3).

RESULTS

Group 3 consumed significantly more energy and absolute carbohydrates than group 1. The MQI and HPPQI scores of group 3 were significantly lower than those of group 1. The HEI score was significantly lower in group 3 compared to group 1, with a mean difference of 8.1 points. Compared to patients with 1-2 years following LSG, those with 2-3 and 3-5 years consumed more refined grains. Eating behavior scores did not differ between groups.

CONCLUSION

Patients at 3-5 years post-LSG consumed more energy and carbohydrates than those at 1-2 years after the surgery. Protein quality, overall macronutrient quality, and overall diet quality decreased as time passed following surgery.

Nutritional Status, Selected Nutrients Intake, and Metabolic Disorders in Bariatric Surgery Patients

Bariatric surgery is the most effective treatment for obesity and its complications. However, failure to adhere to dietary recommendations can result in both unsatisfactory weight loss and metabolic disorders. The aim of this study was to evaluate the effects of bariatric surgery on the anthropometric parameters and selected nutrient intake. A total of 12 months postoperatively, percent excess weight loss (%EWL) was significantly higher after laparoscopic Roux-en-Y gastric bypass (LRYGB) than laparoscopic sleeve gastrectomy (LSG) and laparoscopic adjustable gastric banding (LAGB) (93.78% vs. 56.13% and 55.65%, p < 0.001). The same was true for waist-to-hip ratio (WHR) (p = 0.017) and waist-to-height ratio (WHtR) changes (p = 0.022). There was a significant decrease in total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels after RYGB. A significant decrease (p < 0.05) in daily intake was found for energy (4278.4 kcal vs. 1355.17 kcal), sucrose (122.23 g vs. 38.22 g), dietary fiber (30.90 g vs. 14.20 g), eicosapentaenoic fatty acid and docosahexaenoic acid (EPA+DHA) (142.46 mg vs. 52.90 mg) and % energy from fats (42.43% vs. 35.17%), saturated fatty acids (SAFAs) (19.96% vs. 14.11%) and alpha-linolenic fatty acid (ALA) (0.87% vs. 0.69%). Energy intake and energy % from fats positively correlated with body weight (BW), waist circumference (WC), WHR, and WHtR, and negatively with %EWL. The percentage of unsaturated fatty acids positively correlated with WC and WHR. Energy intake correlated positively with serum triglycerides (TGs) and energy % from fats and carbohydrates. Despite significant weight loss, the patient's diet deviated from recommendations and may have contributed to metabolic disorders.

Changes in dietary intake, food tolerance, hedonic hunger, binge eating problems, and gastrointestinal symptoms after sleeve gastrectomy compared with after gastric bypass; 1-year results from the Oseberg study-a randomized controlled trial

BACKGROUND

The randomized Oseberg study compared the effects of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB), on the 1-y remission of type 2 diabetes and β-cell function (primary outcomes). However, little is known about the comparable effects of SG and RYGB on the changes in dietary intakes, eating behavior, and gastrointestinal discomfort.

OBJECTIVES

To compare 1-y changes in intakes of macro- and micronutrients, food groups, food tolerance, hedonic hunger, binge eating, and gastrointestinal symptoms after SG and RYGB.

METHODS

Among others, prespecified secondary outcomes were dietary intake, food tolerance, hedonic hunger, binge eating, and gastrointestinal symptoms assessed with a food frequency questionnaire, food tolerance questionnaire, Power of food scale, Binge eating scale, and Gastrointestinal symptom rating scale, respectively.

RESULTS

A total of 109 patients (66% females), with mean (SD) age 47.7 (9.6) y and body mass index of 42.3 (5.3) kg/m², were allocated to SG (n = 55) or RYGB (n = 54). The SG group had, compared with the RYGB group, greater 1-y reductions in the intakes of: protein, mean (95% CI) between-group difference, -13 (-24.9, -1.2) g; fiber, -4.9 (-8.2, -1.6) g; magnesium, -77 (-147, -6) mg; potassium, -640 (-1237, -44) mg; and fruits and berries, -65 (-109, -20) g. Further, the intake of yogurt and fermented milk products increased by >2-folds after RYGB but remained unchanged after SG. In addition, hedonic hunger and binge eating problems declined similarly after both surgeries, whereas most gastrointestinal symptoms and food tolerance remained stable at 1 y.

CONCLUSIONS

The 1-y changes in dietary intakes of fiber and protein after both surgical procedures, but particularly after SG, were unfavorable with regard to current dietary guidelines. For clinical practice, our findings suggest that health care providers and patients should focus on sufficient intakes of protein, fiber, and vitamin and mineral supplementation after both SG and RYGB. This trial was registered at [clinicaltrials.gov] as [NCT01778738].

Association Between Energy and Macronutrient Intakes and Weight Change After Bariatric Surgery: a Systematic Review and Meta-analysis

OBJECTIVES

This systematic review and meta-analysis aimed to summarize the evidence on the associations of energy and macronutrient intakes (carbohydrates, fats, and proteins) with weight loss in adults after sleeve gastrectomy or gastric bypass and to determine whether these dietary characteristics of patients with suboptimal weight loss (SWL) or weight regain differ from those without these experiences.

METHODS

PubMed, Scopus, and Web of Science were searched until December 2021. Twenty-three observational studies were included.

RESULTS

Studies on the association of postoperative energy and macronutrients and weight loss used diverse approaches. Pooled results showed that patients with SWL consumed more energy than those with acceptable weight loss. Weight regainers consumed more energy and carbohydrates and less protein than non-regainers.

CONCLUSIONS

Higher energy consumption is related to SWL and weight regain after surgery. Associations between macronutrients and weight outcome following bariatric surgery warrant further investigation.

Assessment of the Clinical Condition and Way of Patients' Nutrition before and after Laparoscopic Sleeve Gastrectomy

One of the most commonly performed bariatric procedures is the laparoscopic sleeve gastrectomy (LSG). It is highly effective in reducing body weight, but it carries the risk of developing nutritional deficiencies and their consequences. The aim of the study was to determine the clinical condition of obese patients after LSG in terms of nutritional status, metabolic disorders, and way of nutrition. Thirty participants (15 women and 15 men) took part in the study. A statistically significant reduction in the total body fat mass (women by 37.5% p < 0.05, men by 37.06% p < 0.05) and total fat free mass (women by 10% p < 0,05, men by 12.5% p < 0.05) was demonstrated 6 months after LSG. Moreover, insufficient protein intake has been shown in over 73% of women and 40% of men. Before and 6 months after LSG, insufficient intake of calcium, magnesium, potassium, folate, vitamin D, and iron was observed. Six months after the LSG, significant decreases of fasting glucose (p < 0.05), insulin (p < 0.05), TG (p < 0.05), and AST (p < 0.05) concentrations, were observed in both groups. Optimization of nutrition in order to prevent nutritional deficiencies and their complications is a key element of the therapy of obese patients treated surgically.

Prevalence of anemia and related nutrient deficiencies after sleeve gastrectomy: A systematic review and meta-analysis

This study aimed to investigate the prevalence of anemia and related nutrient deficiencies after sleeve gastrectomy (SG). Four online databases were searched for relevant articles. Thirty-one studies with 7639 patients were included in the meta-analysis. The pooled anemia prevalence was 7%, 6%, 9%, 10%, 12%, 25%, 20%, and 18% at baseline, 3 months, 6 months, 12 months, 24 months, 36 months, 48 months, and 60 months, respectively. Although the prevalence of vitamin B12 and folate deficiencies remained low postoperatively, the prevalence of ferritin deficiency steadily increased from 6% at baseline to 27% at 60 months. The prevalence of serum iron deficiency decreased from 13% at baseline to 6% at 24 months and increased to 20% at 60 months. Anemia and ferritin deficiency were strongly correlated (Pearson correlation coefficient = 0.774, p = 0.041). Subgroup analysis suggested that age ≤40 years, preoperative anemia, and insufficient iron supplementations were high-risk factors for postoperative anemia. SG is associated with an increased risk of anemia and decreased iron storage over long-term observation. Routine iron supplementations may reduce anemia after SG; however, the dosages recommended by current guidelines may be insufficient. More strict monitoring schedules and supplementation strategies should be established for the timely detection and management of postoperative anemia.

Higher magnesium levels are associated with better glycaemic control and diabetes remission post-bariatric surgery

BACKGROUND

Low Magnesium (Mg) dietary intake has been associated with increased risk of type 2 diabetes mellitus (T2DM). Furthermore, in patients with T2DM, hypomagnesemia is associated with worst glycaemic control. Bariatric surgery (BS) remains the most effective treatment in severe obesity and also provides resolution/improvement of T2DM. Our aim is to evaluate the association between Mg supplementation post-BS and Mg serum levels with diabetes status after BS.

METHODS

We performed an observational study on patients with obesity and T2DM who underwent BS. Data was assessed pre-BS and one-year post-BS.

RESULTS

We included a total of 403 patients with T2DM. At baseline, 43.4% of the patients had Mg deficiency. Pre-BS, patients with Mg deficiency had poorer glycaemic control - HbA1c 7.2 ± 1.6% vs 6.4 ± 1.0% (p < 0.001), fasting plasma glucose 146.2 ± 58.8 mg/dL vs 117.5 ± 36.6 mg/dL (p < 0.001) and were under a greater number of anti-diabetic drugs 1.0 (IQR 0-2.0) vs 1.0 (IQR 0-1.0) (p = 0.002). These findings persisted at one-year post-BS. At the first-year post-BS, 58.4% of the patients had total remission of T2DM and 4.1% had partial remission. Patients without Mg deficiency at one-year post-BS had higher rates of total and partial remission. Higher serum Mg levels at baseline is an independent predictor of total T2DM remission (p < 0.0001). The optimal cut-off of baseline Mg to predict total T2DM remission was 1.50 mg/dL with a sensitivity of 73% and a specificity of 58% (area under ROC = 0.65). Patients that were under Mg supplementation post-BS had serum Mg values, glycaemic control and total remission of T2DM similar to patients non-supplemented.

CONCLUSION

In patients with T2DM submitted to BS, higher Mg serum levels at baseline and 1-year after BS were associated with better glycaemic control and higher rates of total T2DM remission at the first year post-BS.

Hypocalcemia After Thyroidectomy in Patients with Prior Bariatric Surgery: A Propensity Score Matched Analysis from a National Administrative Database

Background: Studies have suggested that patients with prior gastric bypass may be at increased risk for hypocalcemia following thyroidectomy. Unfortunately, most of these studies are limited to case reports and small series. This study represents the largest sample size to date to assess the incidence of post-thyroidectomy hypocalcemia in patients with a history of bariatric surgery. Methods: The TriNetX Research Network was queried to retrospectively identify patients with prior bariatric surgery who underwent total thyroidectomy between 2011 and 2021. The incidence of hypocalcemia following surgery was compared with patients who underwent total thyroidectomy, and hemithyroidectomy with no history of bariatric surgery. Results: We identified 446 patients with a history of bariatric surgery and subsequent thyroidectomy, 29,346 patients with total thyroidectomy, and 19,603 patients with hemithyroidectomy alone. The one-month incidence of hypocalcemia was 54.7% in those with a history of bariatric surgery who underwent thyroidectomy, 43.9% in those with thyroidectomy alone (relative risk, RR = 1.2 [confidence interval, CI 1.1-1.4], p < 0.001), and 8.1% in those with hemithyroidectomy only (RR = 6.8 [CI 6.1-7.4], p < 0.001). Permanent hypocalcemia was documented in 11.4% of patients with prior bariatric surgery who underwent thyroidectomy, 7.7% of those with thyroidectomy only (RR = 1.5 [CI 1.1-1.9], p = 0.003), and 2.9% of patients with hemithyroidectomy alone (RR = 3.9 [CI 3.0-5.2], p < 0.001). Significant differences persisted after matching demographics, prior need for supplementation, and risk factors for hypocalcemia after thyroidectomy. When stratified by bariatric procedure, patients with a history of Roux-en-Y gastric bypass (RYGB) (n = 35) had a greater, although not statistically significant, risk of short-term hypocalcemia (51.4%; RR = 1.2 [CI 0.8-1.6], p = 0.37), and a significantly increased risk of permanent hypocalcemia (20.0%; RR = 2.6 [CI 1.3-5.1], p = 0.005) compared with thyroidectomy alone. Sleeve gastrectomy (SG) (n = 40) was not associated with an increased risk of short-term (40.0%; RR = 0.9 [CI 0.6-1.3], p = 0.62) or permanent (7.5%; RR = 1.0 [CI 0.3-2.9], p = 0.96) hypocalcemia. Conclusions: Prior RYGB, but not SG, may increase the risk of permanent hypocalcemia after thyroidectomy. Additional research is necessary to determine optimal prevention and treatment strategies to reduce morbidity in this population.

Potential associations between alterations in gut microbiome and obesity-related traits after the bariatric surgery

AIM

This study aimed to examine the effects of both obesity and bariatric surgery on gut microbiome, dietary intake, as well as metabolic and inflammatory parameters.

METHODS

All participants (15 with morbid obesity who had bariatric surgery, 8 with morbid obesity and 11 non-obese) were followed-up for a 6-month period with the interviews at baseline (M0), at the end of 3 (M3) and 6 months (M6). Dietary assessment was done, and blood and faecal samples were collected.

RESULTS

Dietary energy and nutrient intakes as well as serum levels glucose, total cholesterol, LDL-cholesterol, and hs-CRP levels decreased by surgery (p<0.05, for each). Participants with morbid obesity had higher levels of Firmicutes and lower levels of Bacteroidetes at M0 compared to non-obese participants. The abundances of Bacteroidetes increased (p=0.02) while Firmicutes decreased (p>0.05) by the surgery, leading a significant decrease in Firmicutes/Bacteroidetes ratio (p=0.01). At sub-phylum level, the abundances of Lactobacillus and Bifidobacterium decreased while Akkermansia increased by the surgery (p<0.01, for each). Although participants who are morbidly obese had a distinct profile according to ß-diversity indices at M0, it became similar with the profile of non-obese participants (p>0.05) at M3 and M6. Similarly, α-diversity indices were lower in subjects with morbid obesity at M0, but became similar to levels in non-obese controls at M6.

CONCLUSION

This study confirmed that bariatric surgery has substantial impacts on gut microbiome composition and diversity, as well as anthropometrical measurements and biochemical parameters, which were associated with the alterations in dietary intake patterns. This article is protected by copyright. All rights reserved.

The need and safety of vitamin supplementation in adults with obesity within 9 months post sleeve gastrectomy (SG): assessment based on intake

The aim of the study was to assess the need and safety of vitamin supplementation in adults with obesity post bariatric surgery (SG), based on intake assessment. Patients with obesity class III, and with obesity class II with comorbidities were followed up at 3, 6 and 9 months post bariatric surgery. Based on a 4-day food record questionnaire, the intake of vitamins and calories was assessed and an interview regarding the consumption of supplements was conducted. The study showed a deficiency in the dietary intake of vitamin D, folate (B₉) and vitamin B₁ (in 93–100% of respondents), vitamins E and C (in 53–67% of respondents), vitamins A, PP and vitamins B₂ and B₆ (in 10 to 23% of respondents) and vitamin B₁₂ (only 1 woman). The intake of multivitamin supplements was implemented by 72% of respondents, independently, all patients were taking a vitamin D supplement. Vitamin deficiencies were only reported in a small percentage of patients (3–17%), who did not take supplements throughout the observation period. Supplementation with vitamins D, E, C, B₁ and folic acid (B₉), used regularly, supplemented the nutritional deficiencies of patients. The intake of vitamin A, B₂, PP, and B₆ with supplements did not significantly affect the overall intake. Supplementation with vitamin B₁₂ turned out to be unjustified to the nutritional recommendations. The dietary and/or supplemental intake of vitamins did not exceed the tolerable upper intake level (UL). The results of the study confirm the need to implement vitamin supplementation for bariatric patients and its safety.

Gut microbiome: Linking together obesity, bariatric surgery and associated clinical outcomes under a single focus

Obesity is increasingly prevalent in the post-industrial era, with increased mortality rates. The gut microbiota has a central role in immunological, nutritional and metabolism mediated functions, and due to its multiplexity, it is considered an independent organ. Modern high-throughput sequencing techniques have allowed phylogenetic exploration and quantitative analyses of gut microbiome and improved our current understanding of the gut microbiota in health and disease. Its role in obesity and its changes following bariatric surgery have been highlighted in several studies. According to current literature, obesity is linked to a particular microbiota profile that grants the host an augmented potential for calorie release, while limited diversity of gut microbiome has also been observed. Moreover, bariatric surgery procedures represent effective interventions for sustained weight loss and restore a healthier microbiota, contributing to the observed fat mass reduction and lean mass increase. However, newer evidence has shown that gut microbiota is only partially recovered following bariatric surgery. Moreover, several targets including FGF15/19 (a gut-derived peptide), could be responsible for the favorable metabolic changes of bariatric surgery. More randomized controlled trials and larger prospective studies that include well-defined cohorts are required to better identify associations between gut microbiota, obesity, and bariatric surgery.

Does Bypass of the Proximal Small Intestine Impact Food Intake, Preference, and Taste Function in Humans? An Experimental Medicine Study Using the Duodenal-Jejunal Bypass Liner

The duodenal-jejunal bypass liner (Endobarrier) is an endoscopic treatment for obesity and type 2 diabetes mellitus (T2DM). It creates exclusion of the proximal small intestine similar to that after Roux-en-Y Gastric Bypass (RYGB) surgery. The objective of this study was to employ a reductionist approach to determine whether bypass of the proximal intestine is the component conferring the effects of RYGB on food intake and sweet taste preference using the Endobarrier as a research tool. A nested mechanistic study within a large randomised controlled trial compared the impact of lifestyle modification with vs. without Endobarrier insertion in patients with obesity and T2DM. Forty-seven participants were randomised and assessed at several timepoints using direct and indirect assessments of food intake, food preference and taste function. Patients within the Endobarrier group lost numerically more weight compared to the control group. Using food diaries, our results demonstrated similar reductions of food intake in both groups. There were no significant differences in food preference and sensory, appetitive reward, or consummatory reward domain of sweet taste function between groups or changes within groups. In conclusion, the superior weight loss seen in patients with obesity and T2DM who underwent the Endobarrier insertion was not due to a reduction in energy intake or change in food preferences.

Anemia After Sleeve Gastrectomy and One-Anastomosis Gastric Bypass: An Investigation Based on the Tehran Obesity Treatment Study (TOTS)

BACKGROUND

Bariatric surgery has been associated with iron, folate, and vitamin B12 deficiencies, which can lead to anemia. This study compares the incidence of anemia between sleeve gastrectomy (SG) and one-anastomosis gastric bypass (OAGB).

METHODS

Patients from a prospectively collected database of patients with morbid obesity undergoing a primary bariatric procedure from April 2013 to September 2018 were included. Statistical analysis was performed using the general estimation equation. Patients were followed for 6, 12, 24, and 36 months post-surgery.

RESULTS

The present study included 2618 patients, of whom 72.3% underwent SG and 27.6% underwent OAGB. The majority of the study population were women (75.7%), and the mean age of the participants was 39.5 ± 11.7 years. At the end of the follow-up, the excess weight loss percentage was 66.15 in the SG group and 75.41 in the OAGB group (P <  0.05). The incidence of anemia at 12-, 24-, and 36-month was 16.2, 19.7, and 24.3% in the SG group and 28.4, 37.6, and 56.5% in the OAGB group, showing significantly higher incidence in the OAGB than the SG group ([Formula: see text] < 0.001). However, there was no significant difference between the SG and OAGB groups regarding the incidence of iron and vitamin B12 deficiency.

CONCLUSIONS

The patients undergoing bariatric surgery, especially OAGB, should be closely monitored post-surgery regarding the incidence of anemia, and supplementation in developing countries could be continued even after the first year.

Vitamin B Complex Deficiency After Roux-en-Y Gastric Bypass and Sleeve Gastrectomy-a Systematic Review and Meta-Analysis

Bariatric surgery, although an effective method, still has complications, like nutritional deficiencies. Our aim was to summarize the evidence on the frequency of complex B vitamin deficiencies in studies comparing Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). We included 25 studies for qualitative synthesis and 21 studies for quantitative synthesis. Relevant data was extracted, including proportion of patients with deficiency and mean serum vitamin values in 3 different timeframes. B12 and folate were the most prevalent deficiencies. B12 deficiency was more common after RYGB and folate serum mean levels were higher after RYGB. SG causes less nutrient deficiency and is therefore a better technique from this point of view. More studies are needed on B2, B3, and B6 vitamins to draw better conclusions.

Evaluation of the impact of gastric bypass surgery on eating behaviour using objective methodologies under residential conditions: Rationale and study protocol

Gastric bypass surgery leads to significant and sustained weight loss and a reduction in associated health risks in individuals with severe obesity. While reduced energy intake (EI) is the primary driver of weight loss following surgery, the underlying mechanisms accounting for this energy deficit are not well understood. The evidence base has been constrained by a lack of fit-for-purpose methodology in assessing food intake coupled with follow-up studies that are relatively short-term. This paper describes the underlying rationale and protocol for an observational, fully residential study using covert, objective methodology to evaluate changes in 24-hr food intake in patients (n = 31) at 1-month pre-surgery and 3-, 12- and 24-months post-surgery, compared to weight-stable controls (n = 32). The main study endpoints included change in EI, macronutrient intake, food preferences, and eating behaviours (speed, frequency, and duration of eating). Other physiological changes that may influence EI and weight regulation including changes in body composition, circulating appetite hormones, resting metabolic rate, total energy expenditure and gastrointestinal symptoms were also evaluated. Understanding which mechanisms contribute to a reduction in EI and weight loss post-surgery could potentially help to identify those individuals who are most likely to benefit from gastric bypass surgery as well as those that may need more targeted intervention to optimise their weight loss post-surgery. Furthermore, clarification of these mechanisms may also inform targeted approaches for non-surgical treatments of obesity.

Macro- and Micro-nutrient Intake Adequacy in Gastric Bypass Patients after 24 Months: a Cross-sectional Study

Decreased food intake is an effective mechanism for gastric bypass surgery (GBS) for successful weight loss. This cross-sectional study aimed to assess dietary intake, micro-and macro-nutrients in the patients undergoing GBS and determine the possible associations with weight changes. We assessed anthropometric indices and food intake at 24 month-post gastric bypass surgery. Dietary data was evaluated using three-day food records. After the 24 months of surgery, among 35 patients (mean age: 43.5 ± 11.2 years; 82.85% females), with the mean body mass index (BMI) of 30.5 ± 4.5 kg/m², 17 cases were < 50% of their excess weight. The average daily calorie intake was 1,733 ± 630 kcal, with 14.88% of calories from protein. Consumption amounts of protein (0.82 ± 0.27 g/kg of the current weight), as well as fiber, and some micro-nutrients (vitamin B9, E, K, B5, and D3) were lower than recommended amounts. Patients were classified into three groups based on their success in weight loss after surgery. Calorie intake was not significantly different between groups, but successful groups consumed considerably more protein and less carbohydrate than the unsuccessful group (p < 0.05). Based on our findings, the patients undergoing GBS had inadequate macro- and micro-nutrient intake after 24 months. However, protein intake can affect patients' success in achieving better weight loss. Long-term cohort and clinical studies need to be conducted to comprehend this process further.

Preventing calcium and vitamin D deficiencies following weight loss and metabolic surgery

Introduction

Uncertain nutritional outcomes following common metabolic surgical techniques are concerning given the long-term potential for postoperative metabolic bone disease. This study aims to investigate the variations in serum calcium, vitamin D, and parathyroid hormone (PTH) levels following Roux-en-Y Gastric bypass (RYBP) and Sleeve Gastrectomy (SG).

Methods

A retrospective analysis of 370 patients who underwent metabolic surgery at a single-centre group practice in Melbourne, Australia, over 2 years.

Results

Patients underwent SG (n = 281) or RYGP (n = 89), with 75% and 87% of the cohort being female, respectively. Postoperative mean serum calcium levels and median serum vitamin D levels improved significantly by 24 months within both cohorts. Serum PTH levels within the RYBP group were significantly higher than the SG group across all time points. PTH levels significantly fell from 5.7 (IQR 4.2–7.4) to 5.00 (4.1–6.5) pmol/L by 24 months following SG. However, PTH levels following RYBP remained stable at 24 months, from 6.1 (IQR 4.7–8.7) to 6.4 (4.9–8.1) pmol/L. Furthermore, we failed to notice a significant improvement in PTH levels following RYBP among those with higher PTH levels preoperatively.

Conclusion

Higher PTH levels following RYBP, compared to SG, may imply we are undertreating patients who are inherently subjected to a greater degree of malabsorption and underlying nutritional deficiencies. This finding calls for a tailored supplementation protocol, particularly for those with high preoperative PTH levels undergoing RYBP, to prevent deficiencies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-021-01348-3.

Iron supplementation following bariatric surgery: A systematic review of current strategies

Iron deficiency (ID) and iron deficiency anemia (IDA) are common following bariatric surgery; however, there are limited standardized treatment recommendations for their management. The purpose of this study was to review the current strategies for iron supplementation following bariatric surgery and assess their relative efficacy in managing ID and IDA. MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched to January 2021. Primary outcomes of interest were prevention or improvement in ID or IDA with iron supplementation. Forty-nine studies with 12,880 patients were included. Most patients underwent Roux-en-Y gastric bypass (61.9%). Iron supplementation was most commonly administered orally for prevention of ID/IDA and was effective in 52% of studies. Both IV and oral iron were given for treatment of ID/IDA. Fifty percent (3/6) of the oral and 100% (3/3) of the IV supplementation strategies were effective at treating ID. Iron supplementation strategies employed following bariatric surgery are highly variable, and many do not provide sufficient iron to prevent the development of ID and IDA, potentially due to poor patient adherence. Further high-quality prospective trials, particularly comparing intravenous and oral iron, are warranted in order to determine the ideal dosage, route, and duration of iron supplementation.

The Need and Safety of Mineral Supplementation in Adults with Obesity Post Bariatric Surgery-Sleeve Gastrectomy (SG)

PURPOSE

Most of the research indicated that daily dietary intake of minerals in SG patients was lower than the current recommendations. The aim of the study was to assess the need and safety of a mineral supplementation practice in adults with obesity, at 3, 6, and 9 months post bariatric surgery-sleeve gastrectomy (SG).

METHODS

The study included 24 women and 6 men. Based on a 4-day food record questionnaire, mineral and calorie intake was calculated at 3, 6, and 9 months after bariatric surgery (SG). Furthermore, an interview on supplement intake was also conducted.

RESULTS

It was found that in both men and women, there was a dietary intake deficiency of calcium (97% of respondents), potassium (97%), magnesium (83%), sodium (60%), and zinc (53%). In women, the deficiencies also included iron (50%) and copper (29%). Only 72% of the patients took dietary supplements. The applied supplementation did not adjust for the required intake of calcium in all of the patients, as well as the intake of magnesium in the male patients. Low intake of sodium and potassium were not supplemented and should be corrected by diet modification. The patients did not require supplementation of phosphorus or manganese, while male patients did not require iron or copper supplementation. The dietary and/or supplemental intake of minerals did not exceed the tolerable upper intake level (UL).

CONCLUSION

The results of the study confirm the need to implement personalized mineral supplementation for bariatric surgery patients.

Understanding the Experience of Osteoporosis Risk in Bariatric Surgical Patients

Despite what is known about risk factors, preventive treatment, and increased prevalence of fragility fractures in post-bariatric surgical patients, little is known about how patient perspectives of osteoporosis risk inform their commitment to bone health. The purpose of this study was to examine the lived experience of osteoporosis risk in people who have had bariatric surgery. Interpretive phenomenology was used to explore osteoporosis from the perspectives of patients who have had bariatric surgery. Eligibility criteria included female, age older than 18 years, and able to understand and speak English. This research provided an understanding of the risk of osteoporosis from the constructed realities and experiences of those who have had bariatric surgery. Participants in this study incorrectly felt they had little to no risk for osteoporosis after bariatric surgery. Patients need to be aware of an increased risk for osteoporosis leading to the potential for fragility fractures after bariatric surgery; nurses are well positioned to enhance osteoporosis prevention efforts in this population through pre- and postoperative education.

Micronutrient status in bariatric surgery patients receiving postoperative supplementation per guidelines: Insights from a systematic review and meta-analysis of longitudinal studies

The micronutrient status and optimal monitoring schedule after bariatric surgery have not been sufficiently assessed. This systematic review and meta-analysis investigated the longitudinal changes in micronutrient status after bariatric surgery. PubMed, EMBASE, and Cochrane Library were searched for articles that measured preoperative and postoperative serum micronutrient levels in patients undergoing Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). Among guideline-adherent studies, the longitudinal changes in micronutrient status were investigated using weighted mean difference (WMD) using a random-effects model. Among the 82 included studies, the guideline adherence rates for micronutrient supplementation after bariatric surgery did not exceed 20%. In patients supplemented per guidelines, vitamin A significantly decreased after RYGB by -7.54 (95% confidence interval [CI], -10.16 to -4.92) μg/dl at 12-23 months, vitamin E decreased after RYGB by -2.35 (95% CI, -3.65 to -1.05) μg/dl at ≥24 months, and ferritin by -54.93 (95% CI, -77.19 to -32.67] μg/L at ≥24 months after SG, compared with baseline, with moderate level of evidence. Significant decreases in micronutrient levels at certain follow-up intervals in studies with supplementation per guidelines need to be considered to establish a post-bariatric micronutrient monitoring schedule for timely detection and management of micronutrient deficiencies.

Evaluation of Dietary Assessment Tools Used in Bariatric Population

Severe obesity is associated with major health issues and bariatric surgery is still the only treatment to offer significant and durable weight loss. Assessment of dietary intakes is an important component of the bariatric surgery process. Objective: To document the dietary assessment tools that have been used with patients targeted for bariatric surgery and patients who had bariatric surgery and explore the extent to which these tools have been validated. Methods: A literature search was conducted to identify studies that used a dietary assessment tool with patients targeted for bariatric surgery or who had bariatric surgery. Results: 108 studies were included. Among all studies included, 27 used a dietary assessment tool that had been validated either as part of the study per se (n = 11) or in a previous study (n = 16). Every tool validated per se in the cited studies was validated among a bariatric population, while none of the tools validated in previous studies were validated in this population. Conclusion: Few studies in bariatric populations used a dietary assessment tool that had been validated in this population. Additional studies are needed to develop valid and robust dietary assessment tools to improve the quality of nutritional studies among bariatric patients.

Methodological issues in assessing change in dietary intake and appetite following gastric bypass surgery: A systematic review

Gastric bypass surgery is an effective long-term treatment for individuals with severe obesity. Changes in appetite, dietary intake, and food preferences have all been postulated to contribute to postoperative body weight regulation, however, findings are inconsistent. The aim of this systematic review was to evaluate the current literature on changes in dietary intake and appetite following gastric bypass surgery, in the context of the methodology used and the analysis, interpretation, and presentation of results. Four databases were systematically searched with terms related to "gastric bypass surgery," "appetite," and "dietary intake," and 49 papers (n = 2384 patients after gastric bypass) were eligible for inclusion. The evidence indicated that only a reduction in overall energy intake and an increase in postprandial satiety are maintained beyond 6-month post-surgery, whereas relative macronutrient intake and premeal hunger remain unchanged. However, available data were limited by inconsistencies in the methods, analysis, presentation, and interpretation of results. In particular, there was a reliance on data collected by subjective methods with minimal acknowledgment of the limitations, such as misreporting of food intake. There is a need for further work employing objective measurement of appetite and dietary intake following gastric bypass surgery to determine how these mechanisms may contribute to weight regulation in the longer term.

Nutritional consequences of endoluminal gastroplasty in the treatment of morbidly obese patients

BACKGROUND

The Endoscopic sleeve gastroplasty (ESG) is one of the new advanced restrictive techniques of bariatric endoscopy. The principle of this bariatric technique is the reduction of stomach volume through endoscopic plication. The long-term efficacy and metabolic effects of this procedure are the subject of this study.

METHODS

20 patients were enrolled; four men, sixteen women. Then they were followed for 24 months in terms of glycemic control, body composition, vitamin, and nutritional status. Observed parameters included glucose, triacylglycerols, high- and low-density lipoprotein cholesterol, micro and macro nutrients, fat mass, and lean body mass.

RESULTS

We observed significant weight loss and a decrease body composition resulted from procedure vs. baseline, with levels of blood glucose also showing statistically significant reductions. The most notable decline in measured values was observed in period six months after the procedure. No significant changes were observed in measurement of micronutrients.

CONCLUSIONS

Good restriction results were obtained following ESG, which might be mediated via altered glucose metabolism. The ESG method has shown a positive effect on fat and muscle mass. Unlike surgical methods, there were no deficits or deficiencies, especially in terms of essential vitamin levels.

The prevalence of zinc deficiency in morbidly obese patients before and after different types of bariatric surgery

BACKGROUND

The prevalence of obesity is considered to be increased worldwide. Lack of mineral elements is one of the essential side effects of bariatric surgery as a trending treatment for obesity. We aimed to assess zinc deficiency among morbidly obese patients before and following different types of bariatric surgical procedures.

METHODS

In the present retrospective cohort study, 413 morbidly obese patients (body mass index (BMI) ≥ 40 kg/m2 or BMI ≥ 35 kg/m2 with a complication or risk factor, e.g., diabetes mellitus) were enrolled who received bariatric surgery, aged between 18 and 65 years old, and had a negative history of active consumption of alcohol and illicit drugs. Patients were assigned into three groups of bariatric surgeries: mini-gastric bypass, Roux-en-Y gastric bypass (RYGB), and sleeve gastrectomy (SG). We recorded baseline clinical and demographic characteristics and zinc serum levels during the preoperative and postoperative follow-up periods at three, six, and 12 months after the operation.

RESULTS

All patients with a mean age of 40.57 ± 10.63 years and a mean preoperative BMI of 45.78 ± 6.02 kg/m2 underwent bariatric surgery. 10.2% of the bariatric patients experienced zinc deficiency before the surgery, and 27.1% at 1 year after the surgery. The results showed that 27.7% of mini-gastric bypass patients, 29.8% of RYGB, and 13.3% of SG experienced zinc deficiency 12 months following surgery. We observed no statistical differences in the preoperative and postoperative zinc deficiency between different types of surgeries.

CONCLUSION

A high prevalence of preoperative zinc deficiency among morbidly obese patients who underwent bariatric surgery was observed, which increased during the postoperative periods. We recommend assessing zinc serum levels and prescribing zinc supplements before the bariatric operation to alleviate the prevalence of zinc deficiency after the operation.

Acquired Refractory Iron Deficiency Anemia

Anemia is a global health problem affecting one-third of the world population, and half of the cases are due to iron deficiency (ID). Iron deficiency anemia (IDA) is the leading cause of disability in several countries. Although multiple mechanisms may coexist, ID and IDA causes can be classified as i) insufficient iron intake for the body requirement, ii) reduced absorption, and iii) blood losses. Oral iron represents the mainstay of IDA treatment. IDA is defined as "refractory" when the hematologic response after 4 to 6 weeks of treatment with oral iron (an increase of >=1 g/dL of Hb) is absent. The cause of iron-refractory anemia is usually acquired and frequently related to gastrointestinal pathologies, although a rare genetic form called iron-refractory iron deficiency anemia (IRIDA) exists. In some pathological circumstances, either genetic or acquired, hepcidin increases, limiting the absorption in the gut, remobilization, and recycling of iron, thereby reducing iron plasma levels. Indeed, conditions with high hepcidin levels are often under-recognized as iron refractory, leading to inappropriate and unsuccessful treatments. This review provides an overview of the iron refractory anemia underlying conditions, from gastrointestinal pathologies to hepcidin dysregulation and iatrogenic or provoked conditions, and the specific diagnostic and treatment approach.