Micronutrient Deficiencies After Roux-en-Y Gastric Bypass: Long-Term Results

Anemia and iron metabolism disorders after single anastomosis sleeve ileal (SASI) bypass. Is it a real problem?

PURPOSE

SASI (single anastomosis sleeve ileal) bypass can lead to nutritional deficiencies, including disorders of iron metabolism and anemia. This study aims to evaluate the effect of SASI bypass on weight loss, anemia, and iron deficiency in patients with obesity during the follow-up period.

METHODS

This study is a retrospective analysis of prospectively collected data from patients who underwent SASI bypass at our hospital between January 2020 and February 2022.

RESULTS

The mean age of the patients was 42 years (range 22-58). The average duration of the follow-up period was 26 months. The mean percentage of excess weight loss (%EWL) was 90.1%, and total weight loss (%TWL) was 30.5%. During the postoperative observation period, anemia was identified in ten patients (25%), comprising 70% with normocytic anemia, 10% with microcytic anemia, and two macrocytic anemia cases (20%). Iron deficiency was observed in two patients (5%).

CONCLUSION

SASI bypass is an effective bariatric procedure in weight loss outcomes. However, there may be an increased risk of anemia and iron metabolism disruptions associated with this procedure. The common limb length (250 vs. 300 cm) did not significantly impact hemoglobin, iron, TIBC, ferritin levels, or anemia incidence among patients undergoing SASI bypass. The decrease in postoperative ferritin levels signifies a depletion in tissue iron reserves, thereby emphasizing the necessity for surveillance of iron homeostasis parameters following SASI bypass.

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.

Roux-en-Y Gastric Bypass and the Clinical Manifestations of Vitamin Deficiencies: Case Report and Literature Review

This case outlines the complications of Roux-en-Y gastric bypass surgery (RYGBS) and demonstrates clinical manifestations of several vitamin deficiencies. We present a 45-year-old female patient who was admitted to our hospital with generalized weakness, anasarca, hypotension, and failure to thrive, a year after she had her RYGBS. After the procedure, she had nausea, vomiting, and diarrhea with progressive inability to tolerate any oral intake. Subsequently, the patient lost over 200 pounds and got bedridden. Initially, after the procedure, the patient had a dilatation of her anastomotic stricture, but after her surgeon moved out of town she was lost to follow up until she presented to our hospital. Upon arrival, the patient was hypotensive, tachycardic, and appeared dehydrated. The exam also revealed several clinical manifestations of vitamin deficiencies including dermatitis concerning Pellagra, follicular hyperkeratosis, and Bitot spots. Laboratory data showed significantly low albumin, protein, acute kidney injury, and several electrolyte abnormalities. The patient had to be admitted to the ICU for pressure support along with colloid and electrolyte replacement. An Esophagogastroduodenoscopy (EGD) was performed which revealed a clean-based ulcer and a 10-mm anastomotic stricture. She was started on Total Parenteral Nutrition (TPN). After the dilatation of the stricture, the patient was able to tolerate oral intake and TPN was subsequently discontinued upon discharge. The patient was educated extensively on the importance of compliance with daily vitamin supplementation and regular follow-up with bariatric physicians at discharge.

Change in Mineral Status After Bariatric Surgery: a Meta-analysis

BACKGROUND

The risk of protein and vitamin deficiencies after bariatric surgery has been well studied, but the change in mineral status has not gotten enough attention. This study aimed to perform a meta-analysis regarding the change in mineral levels after bariatric surgery and the prevalence of postoperative mineral deficiency, with subgroup analyses of different surgical procedures, study regions, and follow-up time.

METHODS

CENTRAL, PubMed, and EMBASE were searched for related articles. Meta-analysis, subgroup analysis, and sensitivity analysis were performed if necessary.

RESULTS

A total of 107 articles with 47,432 patients were included. The most severe mineral deficiency after bariatric surgery was iron (20.1%), followed by zinc (18.3%), copper (14.4%), chlorine (12.2%), phosphorus (7.5%), and calcium (7.4%). Serum concentrations of potassium, sodium, selenium, manganese, and molybdenum showed no significant change before and after surgery. Subgroup analyses revealed that SG had fewer deficiencies in serum iron, calcium, zinc, magnesium, phosphorus, copper, and selenium than RYGB. OAGB showed a higher incidence of serum iron and zinc deficiencies than RYGB. Studies conducted in different regions also found various mineral statuses after surgery. Studies with follow-up ≥ 5 years had a lower prevalence of zinc, copper, and selenium deficiencies than follow-up < 5 years.

CONCLUSION

A high deficiency rate of serum iron, zinc, copper, chlorine, phosphorus, and calcium was seen after bariatric surgery. The difference in surgical procedures, study regions, and follow-up time may affect postoperative mineral status; more targeted mineral supplement programs are needed considering these influencing factors.

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.

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.

Long-Term Outcomes of Iron Deficiency Before and After Bariatric Surgery: a Systematic Review and Meta-analysis

PURPOSE

This study reviews the prevalence of iron deficiency (ID) in bariatric surgery candidates and the long-term outcomes of the prevalence of ID after bariatric surgery.

MATERIALS AND METHODS

A systematic literature search and meta-analysis were performed in PubMed for articles published by August 31, 2022, including these search terms: bariatric surgery, metabolic surgery, weight loss surgery, obesity surgery, sleeve gastrectomy, gastric banding, gastric bypass, duodenal switch, duodenojejunal bypass, iron, iron deficiency, sideropenia, and hypoferritinemia. Fifty-seven studies examining a total of 26,328 patients with morbidly obese were included in this meta-analysis finally.

RESULTS

The results showed a prevalence of 17% of ID in bariatric surgery candidates and a prevalence of 14%, 17%, 26%, 34%, 23%, 38%, and 23% of ID at 1-, 2-, 3-, 4-, 5-, 8-, and 10-year follow-up after bariatric surgery, respectively. Additionally, the results showed a prevalence of 15%, 19%, 35%, 38%, 29%, 30%, and 23% of ID at 1-, 2-, 3-, 4-, 5-, 8-, and 10-year follow-up after Roux-en-Y gastric bypass, respectively; a prevalence of 12%, 12%, 15%, 31%, and 17% of ID at 1-, 2-, 3-, 4-, and 5-year follow-up after sleeve gastrectomy, respectively; and a prevalence of 19% of ID at 1-year follow-up after anastomosis gastric bypass.

CONCLUSION

As a result, preoperative evaluation and correction of ID may lead to better outcomes for bariatric surgery candidates. ID is also common in patients after bariatric procedures, especially RYGB. Long-term, even lifelong, medical and nutritional monitoring and tailored interventions are critical.

Micronutrient Deficiency Pre- and Post-bariatric Metabolic Surgery in Latin America: a Systematic Review

BACKGROUND

Persons submitted to bariatric metabolic surgery present micronutrient deficiency before and after surgery, due to the lack of proper supplementation. The aim of this study is to establish the prevalence of micronutrient deficiency in people before and after bariatric metabolic surgery in Latin America.

METHODS

This review was conducted in accordance with the 2020 PRISMA Guidelines.

RESULTS

Twenty-seven studies and 2135 participants were included. The highest prevalence of deficiency before surgery was reported for vitamin D (74%), zinc (71%), and hemoglobin (62%); after surgery, they were vitamin A (90.6%), vitamin D (90%), and zinc (68%).

CONCLUSIONS

There is a high prevalence of micronutrient deficiency before and after bariatric metabolic surgery from Latin American persons; the micronutrients with the highest deficiency prevalence were vitamin D before and vitamin A after bariatric metabolic surgery.

Associations of age, sex, and socioeconomic status with adherence to guideline recommendations on protein intake and micronutrient supplementation in patients with sleeve gastrectomy or Roux-en-Y gastric bypass

INTRODUCTION

Patients with bariatric surgery often show poor long-term compliance to recommendations for prevention of nutrient deficiency but it is unclear which factors contribute. We investigated the associations of age, sex, and socioeconomic status (SES) with adherence to guideline recommendations on protein intake and micronutrient supplementation.

METHODS

In a monocentric cross-sectional study we prospectively recruited patients with sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) and a minimum postoperative period of 6 months. Clinical and demographic data were obtained from the patients' medical files and by questionnaire. Patients reported on supplement usage, recorded their dietary intake for seven days and underwent physical examinations including blood testing.

RESULTS

We included 35 patients (SG: n = 25, RYGB: n = 10) with a mean (+SD) postoperative period of 20.2 (±10.4) months. Distributions of age, sex and SES were comparable between the SG and RYGB groups. Non-adherence to recommended protein intake was associated with age ≥ 50 years (p = 0.041) but not sex or SES. Protein intake inversely correlated with markers of obesity. There were no significant associations of age or sex with micronutrient supplementation. Only for vitamins A (p = 0.049) and B1 (p = 0.047) higher SES was associated with greater compliance. The only manifest deficiency associated with non-adherence to micronutrient supplementation was that for folic acid (p = 0.044).

CONCLUSION

In patients after bariatric surgery, those of older age and of lower SES might have a greater risk of unfavorable outcome and may require greater attention to micronutrient and protein supplementation.

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.

Roux-en-Y Gastric Bypass Surgery Leading to Postprandial Hypoglycemia: A Case Report

Postprandial hypoglycemia is a rare complication after Roux-en-Y gastric bypass (RYGB). The underlying pathophysiology remains to be fully understood. We present a case of a 49-year-old woman with a past medical history of mesenteric thrombosis due to prothrombin-related thrombophilia, which culminated in RYGB 10 years prior to presentation. The patient had been given anticoagulation treatment for several years, which she abandoned one year prior to presentation. She presented to our consultation with episodes of postprandial hypoglycemia and severe anemia due to iron and vitamin B12 deficiencies. Dietary adjustments were set in place to prevent hypoglycemia and neuroglycopenic symptoms. Intravenous iron and intramuscular vitamin B12 supplementation led to full recovery of hemoglobin levels, allowing restart of oral anticoagulation to prevent recurrence of thrombotic events.

Vitamin D Deficiency in Patients with Morbid Obesity before and after Metabolic Bariatric Surgery

Background: Metabolic bariatric surgery (MBS) is the most effective treatment for severe obesity. Vitamin D deficiency is a common complication encountered both during preoperative workup and follow-up. Aim: To estimate the prevalence of vitamin D deficiency in patients undergoing MBS. Methods: Prospectively maintained database of our university MBS center was searched to assess the rate of preoperative and postoperative vitamin D deficiency or insufficiency in patients undergoing MBS over a one-year period. Results: In total, 184 patients were included, 85 cases of Sleeve Gastrectomy (SG), 99 Gastric Bypass (GB; 91 One Anastomosis and 8 Roux-en-Y). Preoperative vitamin D deficiency and insufficiency were respectively found in 61% and 29% of patients, with no significant difference between SG and GB. After six months, 15% of patients had vitamin D deficiency, and 34% had vitamin D insufficiency. There was no significant difference in the rate of vitamin D deficiency or insufficiency and the percentage of total weight loss (%TWL) at 1, 3, and 6 postoperative months between SG and GB. Conclusions: Preoperative vitamin D deficiency or insufficiency is common in MBS candidates. Regular follow-up with correct supplementation is recommended when undergoing MBS. Early postoperative values of vitamin D were comparable between SG and OAGB.

Gut microbiota and vitamin status in persons with obesity: A key interplay

There are numerous factors involved in obesity progression and maintenance including systemic low-grade inflammation, adipose tissue dysfunction, or gut microbiota dysbiosis. Recently, a growing interest has arisen for vitamins' role in obesity and related disorders, both at the host and gut bacterial level. Indeed, vitamins are provided mostly by food, but some, from the B and K groups in particular, can be synthesized by the gut bacterial ecosystem and absorbed in the colon. Knowing that vitamin deficiency can alter many important cellular functions and lead to serious health issues, it is important to carefully monitor the vitamin status of patients with obesity and potentially already existing comorbidities as well as to examine the dysbiotic gut microbiota and thus potentially altered bacterial metabolism of vitamins. In this review, we examined both murine and human studies, to assess the prevalence of sub-optimal levels of several vitamins in obesity and metabolic alterations. This review also examines the relationship between vitamins and the gut microbiota in terms of vitamin production and the modulation of the gut bacterial ecosystem in conditions of vitamin shortage or supplementation. Furthermore, some strategies to improve vitamin status of patients with severe obesity are proposed within this review.

Secondary Hyperparathyroidism Before and After Bariatric Surgery: a Prospective Study with 2-Year Follow-Up

PURPOSE

Secondary hyperparathyroidism (SHPT) is linked to obesity. Bariatric surgery may be associated with calcium and vitamin D deficiencies leading to SHPT. This study aimed to detect the prevalence of SHPT before and after bariatric surgery.

METHODS

This prospective study assessed the prevalence of SHPT after sleeve gastrectomy (SG, n = 38) compared to one-anastomosis gastric bypass (OAGB, n = 86). All patients were followed up for 2 years. Bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry.

RESULTS

Of the 124 patients, 71 (57.3%) were females, and 53 (42.7%) were males, with a mean age of 37.5 ± 8.8 years. Before surgery, 23 patients (18.5%) suffered from SHPT, and 40 (32.3%) had vitamin D deficiency. The prevalence of SHPT increased to 29.8% after 1 year and 36.3% after 2 years. SHPT was associated with lower levels of vitamin D and calcium and higher reduction of BMD in the hip but not in the spine. After 2 years, SHPT was associated with a significantly lower T-score in the hip. SHPT and vitamin D deficiency were significantly more common in patients subjected to OAGB compared to SG (p = 0.003, and p < 0.001, respectively). There is a strong negative correlation between vitamin D levels and parathormone levels before and after surgery.

CONCLUSION

Prevalence of SHPT is high in obese patients seeking bariatric surgery, especially with lower vitamin D levels. Bariatric surgery increases the prevalence of SHPT up to 2 years. Gastric bypass is associated with a higher risk of developing SHPT compared to SG.

Improving vitamin D status in bariatric surgery subjects with monthly high-dose ergocalciferol

Background: Vitamin D insufficiency is common before and after bariatric surgery. Optimal supplementation to treat vitamin D insufficiency is not clearly defined. Objective: Determine if serum 25 (OH) D levels improve by the consumption of an additional monthly ergocalciferol supplement by subjects after bariatric surgery. Study design: Thirty-two subjects were randomly divided to receive an additional 100,000 IUs of ergocalciferol monthly after bariatric surgery (n=10) or standard level vitamin D supplement after bariatric surgery (n=22). Serum 25 (OH) D, calcium, and hemoglobin A1c levels were measured preoperatively and one year after bariatric surgery. Results: Mean changes in BMI at 1-year post-operation was -18.12±6.46 kg/m² in the control group versus -18.84±4.7 kg/m²; p=0.638 in the vitamin D group. One year after bariatric surgery, the mean changes from baseline in vitamin D levels were 2.69±9.4 and 12.4±17.0 ng/mL in control and intervention groups, respectively. The treated group showed a marginally higher mean increase in Vitamin D than the control group, p=0.059. Other mean changes at 1-year post-surgery that were not significantly different include calcium -0.264±0.45 and -0.21±0.509 mg/dl in control and intervention groups, respectively and Hgb A1c -1.0±1.21 and -0.95±0.071% in control and intervention groups, respectively. Conclusion: This study showed 100,000 IUs ergocalciferol once a month is a safe and effective treatment for vitamin D insufficiency in most patients having bariatric surgery.

Regular intake of energy drinks and multivitamin supplements is associated with elevated plasma vitamin B6 levels in post-bariatric patients

The aim of the present survey was to analyze plasma vitamin B6 levels in post-bariatric patients and to elucidate the causal factors associated with elevated plasma vitamin B6 levels. This is a retrospective analysis of electronic patient data of all post-bariatric patients evaluated at the endocrine outpatient clinic of the University Hospital Basel in 2017, for which plasma vitamin B6 values were assessed during regular follow-up visits. In total, 205 patients were included in the study, whereof a minority of 43% had vitamin B6 levels in the normal range. 50% of the patients had vitamin B6 levels up to fourfold higher than the upper normal limit and 7% had levels more than fourfold above the upper normal limit. Vitamin B6 deficiency was not observed in any patient. While multivitamin supplementation in general was associated with elevated plasma vitamin B6 levels, the highest vitamin B6 levels were found after biliopancreatic diversion (BPD) and in patients who reported daily energy drink intake. Elevated plasma vitamin B6 levels up to fourfold above the upper normal limit are common in postbariatric patients and are associated with regular multivitamin supplementation, while highly elevated plasma vitamin B6 levels were seen primarily upon regular energy drink intake. Thus, a regular follow-up of vitamin B6 plasma levels and critical evaluation of vitamin B6 supplementation, either as part of the multivitamin preparation or related to regular energy drink intake, is highly warranted and should be an integral part of the routine post-bariatric follow-up.

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.

Impact of the COVID-19 Pandemic and Lockdown on Gastric Bypass Results at 1-Year Follow-up

Purpose

The COVID-19 pandemic caused a lockdown in many countries, which induced negative dietary habits and sedentary behavior. Studies suggest that weight loss of patients undergoing bariatric surgery was equally affected. The aim was to evaluate the impact of COVID-19 on weight loss, obesity-related comorbidities, and nutritional status at 1-year follow-up after gastric bypass (GB).

Methods

Retrospective observational case–control study of patients undergoing primary GB in a tertiary referral Belgian center. COVID-19 period group was composed by those whose 1-year postoperative period was affected by the COVID-19 pandemic and lockdown: from October 1, 2019, to March 31, 2020. The control group was composed of patients operated from October 1, 2018, to March 31, 2019. Electronic clinical records were reviewed searching: baseline characteristics, weight and comorbidities evolution, and biochemical values.

Results

A total of 47 patients in the COVID-19 period group and 66 in the non-COVID-19 period group were analyzed. There were no significant differences in baseline characteristics. A reduced weight loss was observed at 1-year follow-up, in terms of percentage of excess weight loss (%EWL) (82.4% [SD: 21.6] vs. 82.4% [SD: 21.6]; p: 0.043) and body mass index (BMI) (27.8 kg/m² [IQR: 25.8–30.0] vs. 26.2 kg/m² [IQR: 24.6–28.6]; p: 0.029) for COVID-19 period group vs. non-COVID-19 period group, respectively. There was a similar reduction of obesity-related comorbidities, without clinically significant differences in the nutritional follow-up.

Conclusion

The COVID-19 pandemic and lockdown had an impact on weight loss at 1-year follow-up after gastric bypass.

Graphical abstract

Controlling Nutritional Status (CONUT) Score and Micronutrient Deficiency in Bariatric Patients: Midterm Outcomes of Roux-en-Y Gastric Bypass Versus One Anastomosis Gastric Bypass/Mini Gastric Bypass

BACKGROUND

Two of the most common bariatric procedures performed worldwide are Roux-en-Y gastric bypass (RYGB) and one anastomosis gastric bypass (OAGB). Comparative data regarding nutritional status are lacking and no previous study focus on malnutrition according to a validated score.

METHODS

Retrospective data from a single institution were reviewed. Anthropometric variables and nutritional data were assessed. The primary aim was to analyze and compare the nutritional status before and 3 years after RYGB vs OAGB using the controlling nutritional status (CONUT) score. The incidence of micronutrient deficiency and the remission of comorbidities in each group were defined as secondary outcomes.

RESULTS

Fifty-seven patients in each arm were enrolled. A 3-year mild malnutrition (CONUT score 2-3) was found in 38% and 37.05% in the RYGB and OAGB groups, respectively (p > 0.05). In terms of percentage of total weight loss (%TWL) and percentage of adjustable weight loss (%AWL), no differences were found between OAGB and RYGB groups. OAGB and RYGB patients had similar vitamin deficiencies. Anemia, hypoproteinemia, hypoalbuminemia, and hypocalcemia were comparable between groups. At 3-year follow-up, total protein and albumin values were similar between arms while prealbumin deficit was more frequent after OAGB than after RYGB. The rate of type 2 diabetes (87.5% in OAGB and 92% in RYGB), arterial hypertension (51.6% in OAGB and 58.3% in RYGB), and dyslipidemia (69.7% in OAGB and 78.6% in RYGB) remission was not significantly different between the two groups.

CONCLUSIONS

Postoperative CONUT score, micronutrient deficiency, comorbidity remission, and improvement of anthropometric parameters 3 years postoperatively were comparable between RYGB and OAGB groups.

The Effects of Bariatric Surgery on Vitamin B Status and Mental Health

Diet is a modifiable factor that ensures optimal growth, biochemical performance, improved mood and mental functioning. Lack of nutrients, notably vitamin B, has an impact on human health and wellbeing. The United Arab Emirates is facing a serious problem of micronutrient deficiencies because of the growing trend for bariatric surgery, including Roux-en-Y gastric bypass and sleeve gastrectomy. People undergoing bariatric surgery are at high risk of developing neurological, cognitive, and mental disabilities and cardiovascular disease due to deficiency in vitamin B. Vitamin B is involved in neurotransmitter synthesis, including γ-aminobutyric acid, serotonin, dopamine, and noradrenaline. Deficiency of vitamin B increases the risk of depression, anxiety, dementia and Alzheimer's disease. In addition, vitamin B deficiency can disrupt the methylation of homocysteine, leading to hyperhomocysteinemia. Elevated homocysteine levels are detrimental to human health. Vitamin B deficiency also suppresses immune function, increases the production of pro-inflammatory cytokines and upregulates NF-κB. Considering the important functions of vitamin B and the severe consequences associated with its deficiency following bariatric surgery, proper dietary intervention and administration of adequate supplements should be considered to prevent negative clinical outcomes.

Effects of Post-operative Nutritional Disorders Following Bariatric Surgery on Health Care Cost and Use

PURPOSE

Risk of nutritional disorders (NDs) in bariatric surgical patients has led to guideline recommendations for pre- and post-operative nutrient deficiency screening. The aim of this study was to identify baseline factors associated with incident NDs and, in addition, to explore possible differences in health care spending and use between patients with and without incident NDs following bariatric surgery.

MATERIALS AND METHODS

Using data linked with a state-wide bariatric surgical registry and a state-wide claims database, subjects who underwent bariatric surgery between July 1, 2013, and December 31, 2015, were identified. Incident NDs and health care cost and use outcomes following 1 year from surgery were extracted from the claims data. Logistic regression was used to identify baseline factors associated with incident NDs. Zero-inflated negative binomial regression and generalized linear regression were used to estimate health care cost and use outcomes.

RESULTS

A total of 3535 patients who underwent bariatric surgery were identified. Of these patients, those without continuous health insurance enrollment (n=1880), having prevalent (pre-surgery) NDs (n=461), and missing baseline BMI (n=41) were excluded. Of patients analyzed (n=1153), about 30% had incident NDs, with a mean (SD) age and BMI at surgery of 46 (12) years and 48 (9.2) kg/m², respectively. Patients with one incident ND had higher total health care spending (coefficient=$41118, p-value<0.01) and ED visits (IRR=1.86, p-value<0.01).

CONCLUSION

Those without pre-operative NDs may have a higher chance of having NDs post-operatively. Taking multivitamins and continues monitoring are necessary to prevent any negative outcomes related to post-operative NDs.

Haemoglobin and Hematinic Status Before and After Bariatric Surgery over 4 years of Follow-Up

PURPOSE

Bariatric surgery is associated with deficiencies of vitamins and minerals, and patients are routinely advised supplements postoperatively. We studied prevalence of vitamin B12, folate and iron deficiencies and anaemia before and after bariatric surgery over 4 years of follow-up.

MATERIALS AND METHODS

We performed a retrospective cohort analysis of 353 people with obesity, including 257 (72.8%) women, who underwent gastric bypass (252, 71.4%) or sleeve gastrectomy (101, 28.6%) at our National Health Service bariatric centre in Northwest England.

RESULTS

At baseline, mean (standard error) age was 46.0 (0.6) years, body mass index 53.1 (0.4) kg/m2, serum vitamin B12 400.2 (16.4) pg/L, folate 7.7 (0.2) μg/L, iron 12.0 (0.3) μmol/L, ferritin 118.3 (8.4) μg/L and haemoglobin 137.9 (0.8) g/L. Frequency of low vitamin B12 levels reduced from 7.5% preoperatively to 2.3% at 48 months (P < 0.038). Mean folate levels increased from baseline to 48 months by 5.3 μg/L (P < 0.001) but frequency of low folate levels increased from 4.7% preoperatively to 10.3% (P < 0.048). Ferritin levels increased from baseline to 48 months by 51.3 μg/L (P < 0.009). Frequency of low ferritin levels was greater in women (39.1%) than in men (8.9%) at baseline (P < 0.001) and throughout the study period. Haemoglobin was low in 4.6% of all patients at baseline with no significant change over the study period.

CONCLUSION

There were notable rates of haematinic insufficiencies in bariatric surgical candidates preoperatively. Our study lends further support to regular supplementation with vitamin B12, folic acid, and iron in people undergoing bariatric surgery.

Changes in Body Composition and Biochemical Parameters Following Laparoscopic One Anastomosis Gastric Bypass: 1-Year Follow-Up

BACKGROUND/AIM

Little data is available on body composition and biochemical parameter changes after one anastomosis gastric bypass (OAGB) surgery. This study was therefore conducted to assess body composition and biochemical parameter changes in patients who underwent OAGB. The relationship between the percentage of total weight loss (%TWL) with percentage changes in body composition and biochemical parameters was measured in the first year after surgery.

MATERIALS AND METHODS

This retrospective study was carried out on 363 patients (mean age 39.93 ± 9.98 years) who underwent OAGB between January 2011 and November 2018. Anthropometric, body composition and biochemical measurements were recorded before and 1 year after surgery. For paired data, a paired sample t test or Wilcoxon test was used. Spearman or Pearson correlation test was used to evaluate the relationship between % TWL and changes in body composition and biochemical parameters.

RESULTS

The average %TWL at 1 year following surgery was 35.72 ± 6.85. Fat and muscle tissue and also serum levels of glycemic parameters, low density lipoprotein, triglycerides (TG), total cholesterol, zinc, albumin, hemoglobin, hematocrit, and platelet had decreased a year after OAGB (P < 0.05). The postoperative levels of HDL-c, vitamins D, B12, and folic acid were dramatically higher than the preoperative values. Higher %TWL significantly correlated to greater decreases in body fat, muscle mass, and serum TG at 1 year post-surgery, compared to preoperative values.

CONCLUSION

OAGB may be effective over a follow-up period of 1 year in achieving weight, fat mass reduction, and improved serum levels of glycemic parameters and lipid profiles.

The Effect of Bariatric Surgery on Exocrine Pancreatic Function

INTRODUCTION

After bariatric surgery (BS), patients might suffer from nutrient maldigestion, malabsorption, and vitamin deficiencies. In this study, our aim was to assess pancreatic functions after BS using fecal elastase-1 assay (FE-1).

MATERIAL AND METHODS

Sixty patients (21M) undergoing BS and 20 (6M) healthy controls were included into the study. Stool samples were collected 1 year after surgery. Ten patients from one anastomosis gastric bypass (OAGB) and single anastomosis duodenal switch (SADS) groups with the lowest value of FE-1 and GIQLI scores were given pancreatic enzyme replacement therapy (PERT). After PERT, FE-1, excess weight loss (EWL), BMI, GIQLI scores, and vitamin D levels were measured.

RESULTS

Vitamin D levels were detected as 19.04 (9-46.5) pg/ml, 15.1 (8.4-23.6) pg/ml, 17.8 (5-30) pg/ml, and 21.79 (11-40.3) pg/ml after sleeve gastrectomy (SG), OAGB, SADS, and control groups, respectively (p = 0.04). GIQLI scores in the first year were found to have increased in all patients (p = 0.02). FE-1 levels were found as 642.35 (566.3-711.4) μg/g, 378.52 (183.5-561.1) μg/g, 458.88 (252.5-593, 5) μg/g, and 518.2 (351.6-691) μg/g for the SG, OAGB, SADS, and control groups, respectively. There was a strong inverse correlation between EWL and FE-1 levels at the end of the first year (Spearman's rho = - 0.688, p = 0.003). After having performed PERT for patients with the lowest FE-1 levels, the levels increased to 683.39 (615.5-720) μg/g in the OAGB and 691.5 (643.1-720) μg/g in the SADS groups (p = 0.011).

CONCLUSION

FE-1 measurements demonstrated that many patients suffer from malabsorption after OAGB or SADS, whereas functions remain normal after SG. PERT corrects pancreatic functions without affecting weight loss and also contributes to the normal serum level of vitamin D.

Vertical Sleeve Gastrectomy Has Better Weight Evolution and Serum Concentrations of Vitamin D when Compared with Roux-Y Gastric Bypass

OBJECTIVE

The objective of this study is to compare the weight evolution and serum concentrations of vitamin D in individuals undergoing Roux-en-Y Gastric Bypass (RYGB) and Sleeve after 1 follow-up year.

METHODOLOGY

Descriptive, prospective, and longitudinal study, with 108 individuals divided into 2 groups: RYGB (55 patients) and Sleeve (53), evaluated preoperatively, and at 6 and 12 postoperatively months. Anthropometric data, serum concentrations of 25(OH)D, calcium, and parathyroid hormone were analyzed.

RESULTS

The Sleeve group showed greater reductions in excess weight and excess body mass index (BMI) when compared with the RYGB group at both times (p < 0.001). Besides, after 12 months, those who had undergone the Sleeve procedure also had higher percentages of surgical success (84.4% versus 65.0%, p = 0.038). The prevalence of preoperative inadequacy of 25(HO)D in both groups was 78.7%. After 6 months, there was an increase in serum concentrations of 25(HO)D in both groups (p < 0.001), but without significant differences between the groups (p = 0.154). In the comparison between 6 and 12 months, there was only a reduction for the RYGB group (p = 0.001). Also, when comparing both groups, the means of vitamin D in patients undergoing RYGB were also lower after 12 months (p = 0.003). There was a negative correlation between vitamin D and parathyroid hormone (r = - 0.235 p = 0.030). The mean serum concentrations of calcium were adequate at all times.

CONCLUSION

Patients undergoing the Sleeve procedure had a better evolution in weight loss and are at a lower risk of vitamin D inadequacy than those undergoing RYGB.