Prevalence of nutrient deficiencies in bariatric patients. Nutrition. 2009;25:1150-1156. [PMID: 19487104 DOI: 10.1016/j.nut.2009.03.012]

Changes in Nutritional Outcomes After Roux-en-Y Gastric Bypass: A Systematic Review and Meta-Analysis

BACKGROUND

Bariatric surgery (BS) is the most effective treatment for severe obesity and it has beneficial effects on glycemic control and metabolism outcomes. However, the effects of BS on nutritional outcomes are controversial. Therefore, we aimed to evaluate the changes in several nutritional outcomes after Roux-en-Y gastric bypass (RYGB).

METHODS

A comprehensive search was performed using the following databases: PubMed, Embase, Web of Science, Cochrane Library, WanFang and Chinese National Knowledge Infrastructure. The following outcomes were evaluated: vitamin A, 25-hydroxyvitamin D [25(OH)D], calcium, phosphorus, parathormone (PTH), iron, ferritin, vitamin B12, folate, and zinc. The pooled outcomes were expressed as standard mean difference (SMD) and 95% confidence interval (CI) using a random effects model.

RESULTS

Fifty-six studies including 5645 individuals with obesity met the inclusion criteria. Serum 25(OH)D (SMD = 0.78, 95%CI 0.38 to 1.20, P < 0.001), phosphorus (SMD = 0.48, 95%CI 0.22 to 0.74, P < 0.001), PTH (SMD = 0.35, 95%CI 0.11 to 0.59, P = 0.005), vitamin B12 (SMD = 1.11, 95%CI 0.41 to 1.80, P = 0.002), and folate (SMD = 1.53, 95%CI 0.77 to 2.28, P < 0.001) significantly increased after RYGB compared with the baseline. Serum ferritin (SMD =  - 1.67, 95%CI - 2.57 to - 0.77, P < 0.001), vitamin A (SMD =  - 0.64, 95%CI - 0.99 to - 0.29, P < 0.001), and plasma zinc (SMD =  - 0.58, 95%CI - 1.09 to - 0.06, P = 0.027) significantly decreased after RYGB. No significant changes in serum calcium (SMD =  - 0.14, 95%CI - 0.40 to 0.11, P = 0.219) and iron (SMD = 0.26, 95%CI - 0.11 to 0.64, P = 0.165) were observed after RYGB.

CONCLUSIONS

Despite the increased levels of 25(OH)D, phosphorus, vitamin B12 and folate, this meta-analysis revealed the unfavorable nutritional consequences after RYGB.

The role of dietitian follow-ups on nutritional outcomes post-bariatric surgery

BACKGROUND

Current evidence recommends dietary counselling with a registered dietitian (RD) for successful weight loss after metabolic bariatric surgery; however, there are limited data on the effect of RD follow-ups on micronutrient deficiencies. This study evaluated the effects of the number of postoperative RD visits on nutritional outcomes, including weight loss and micronutrient deficiencies.

OBJECTIVES

The aim of this study was to evaluate the effects of the number of postoperative registered dietitian visits on nutritional outcomes, including weight loss and micronutrient deficiencies after metabolic and bariatric surgery.

SETTING

Cleveland Clinic Abu Dhabi, United Arab Emirates METHODS: This retrospective study included patients who underwent bariatric surgery between September 2015 and June 2020. Demographics, weight loss, micronutrients, and the number of postoperative RD visits were evaluated. Baseline and 12-month postsurgery outcomes were compared based on the number of RD follow-ups.

RESULTS

A total of 174 primary and 46 revisions were included. Patients were 73.6% female, with a mean age of 40 years. The initial mean body mass index was 42.8 kg/m2. Number of RD visits were as follows: 0-1 (39 patients), 2 (59 patients), 3 (55 patients), and 4 or more (67 patients). Baseline (pre-operative) micronutrient values were within normal range. In comparison with the reference group (REF = 0-1 post-op RD visits), patients with 3 RD visits had 7% higher total body weight loss (P < .001) and maintained micronutrients within the normal range at 12 months postoperative. Mean differences in postoperative values were statistically significant (P < .05) for weight, vitamin B12, and vitamin D but not for hemoglobin, ferritin, calcium, folate, vitamin B1, copper, and zinc.

CONCLUSION

Our study suggests that three or more RD visits during the first 12 months after bariatric surgery are associated with improved outcomes, including significant percent total body weight loss and lower rates of micronutrient deficiencies.

Infrequent but serious? Beriberi And Thiamine deficiency among adolescents and young adults after bariatric surgery

BACKGROUND

Thiamine deficiency (TD) among adolescents following metabolic and bariatric surgery (MBS) has not been assessed.

OBJECTIVE

We assessed TD among adolescents following MBS.

SETTING

University Hospital.

METHODS

A retrospective chart review was conducted for all adolescents and young adults (aged 10-25 years) who had MBS and subsequently presented with TD at our institution (n = 30). Diagnosis used clinical, laboratory, brain imaging, and neurophysiology criteria. Of 1575 patients, 7 subsequently had TD. Another 23 adolescents had MBS at private hospitals or overseas and presented at our institution with TD.

RESULTS

Based on MBS undertaken at our institution, TD prevalence was .45 cases per 100 MBS. The mean age of patients was 19.5 ± 3.23 years, 53.3% were male, 96.7% had sleeve gastrectomy, and time from MBS to admission averaged 4.97 ± 11.94 months. Mean weight loss from surgery to admission was 33.68 ± 10.90 kg. Associated factors included poor oral intake (90%), nausea and vomiting (80%), and noncompliance with multivitamins (71%). Signs and symptoms included generalized weakness, nystagmus, numbness, and paraparesis (83.3%-80%). Seven patients had Wernicke encephalopathy full triad; 16 displayed a mixed picture of Wernicke encephalopathy and dry beriberi; and there were no cases of wet beriberi. Half the patients achieved complete resolution of symptoms, whereas 47% and 40% had residual weakness or persistent sensory symptoms, respectively. There was no mortality. Most common concurrent nutritional deficiencies were of vitamins K, D, and A.

CONCLUSIONS

This is the first in-depth study of TD among adolescents after MBS. Although TD is uncommon among adolescents after MBS, it is serious, requiring diligent suspicion and prompt treatment. Bariatric teams should emphasize compliance with multivitamin regimens and follow it up.

Bariatric Surgery in Obesity: Metabolic Quality Analysis and Comparison of Surgical Options

Obesity is a constantly growing health problem which reduces quality of life and life expectancy. Bariatric surgery (BS) for obesity is considered when all other conservative treatment modalities have failed. Comparison of the multidisciplinary programs with BS regarding to the weight loss showed that substantial and durable weight reduction have been achieved only with bariatric surgical treatments. Although laparoscopic sleeve gastrectomy is the most popular BS, it has high long-term failure rates, and it is claimed that one of every three patients will undergo another bariatric procedure within a 10-year period. Although BS provides weight loss and improvement of metabolic comorbidities, in long-term follow-up, weight gain is observed in half of the patients, while decrease in bone mass and nutritional deficiencies occur in up to 90%. Moreover, despite significant weight loss, several psychological aspects of patients are worsened in comparison to preoperative levels. Nearly one-fifth of postoperative patients with "Loss-of-eating control" meet food addiction criteria. Therefore, the benefits of weight loss following bariatric procedures alone are still debated in terms of the proinflammatory and metabolic profile of obesity.

Nutrition in Surgery: An Orthopaedic Perspective

➤ Malnutrition is common among subsets of patients undergoing orthopaedic surgery and is associated with an increased risk of postoperative complications.➤ Serum proteins, in particular, albumin, may be used in the evaluation of nutritional status.➤ Anthropometric measurements and surveys also play a role in the evaluation of nutritional status.➤ Increased energy and nutrient requirements due to surgical procedures necessitate increased caloric and protein intake in the perioperative period, which may be achieved through diet or supplementation.➤ Evidence supports the use of protein-calorie, amino acid, and immunonutrition supplements. Vitamin D supplementation is an area of further consideration.➤ Diet restriction, activity alterations, pharmacotherapy, and bariatric surgery are all safe, effective approaches to weight loss, although the optimal timing and magnitude of preoperative weight loss require further investigation.

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.

Joint effect of maternal pre-pregnancy body mass index and folic acid supplements on gestational diabetes mellitus risk: a prospective cohort study

Background

The joint effect of folic acid (FA) supplements and maternal pre-pregnancy body mass index (BMI) on gestational diabetes mellitus (GDM) has not been fully addressed. This study aimed to examine the joint effect of FA supplements and pre-pregnancy BMI on GDM.

Methods

Pregnant women at 4 to 14 weeks of gestation (n = 3186) were recruited during their first prenatal visit in Qingdao from May 1, 2019, to June 27, 2021. The main outcome was GDM at 24–28 weeks’ gestation. Screening was based on 75 g 2-hour oral glucose tolerance (OGTT), a fasting glucose ≥ 5.1 mmol/L, or a 1-hour result ≥ 10.0 mmol/L, or a 2-hour result ≥ 8.5 mmol/L. The interactive effect of FA supplements and pre-pregnancy BMI on GDM was examined using logistic regression analysis and ratio of odds ratios (ROR) was used to compare subgroup differences.

Results

Overall, 2,095 pregnant women were included in the analysis, and GDM incidence was 17.76%. Compared with women with pre-pregnancy BMI lower than 25.0 kg/m² and FA-Sufficient supplements ≥ 400 µg/day (FA-S) population, the adjusted odds ratios (aORs) of FA-S and FA-Deficiency supplements < 400 µg/d (FA-D) were 3.57 (95% confidence interval [CI]: 2.02–6.34) and 10.82 (95% CI: 1.69–69.45) for the obese women (BMI ≥ 30.0 kg/m²), and the aORs of FA-S and FA-D were 2.17 (95% CI: 1.60–2.95) and 3.27 (95% CI: 1.55–6.92) for overweight women (25.0 kg/m² ≤ BMI < 30.0 kg/m²). However, the risk of GDM did not differ significantly between the FA-D and the FA-S group in pre-pregnancy obese women (ROR = 2.70, 95%CI: 0.47–2.30), or overweight women (ROR = 0.66, 95%CI: 0.30–1.49). After further stratification of FA supplementation time, F-D and FA-S in obese women showed an interaction when FA supplement intake time < 3 months. However, there was no significant difference between subgroups (ROR = 1.63, 95% CI: 0.37–7.04).

Conclusion

Maternal pre-pregnancy BMI was associated with the incidence of GDM, the dose of FA supplementation from pre-pregnancy to early pregnancy was not found to be related to the incidence of GDM. The dosage of FA supplement was not associated with GDM irrespective of maternal pre-pregnancy BMI.

Women with Anemia Refractory to Oral Iron Treatment Following Bariatric Surgery: a Short-Term Analysis

INTRODUCTION

Iron deficiency and anemia are common after bariatric surgery. Women have a higher risk of developing such long-term complications. Though oral supplementation is indicated, intravenous iron therapy is required in some cases.

METHODS

This retrospective study included patients who underwent bariatric surgery between 2012 and 2018. Postoperative anemia patients receiving parental iron therapy were assessed during the first 24 months. Their baseline characteristics, surgery type, and laboratory test results were analyzed. A follow-up analysis included a subgroup of women with and without gynecological disorders. Patients with vitamin B12 or folic acid deficiencies were excluded.

RESULTS

Six hundred eleven (63.3%) met the inclusion criteria: 525 underwent gastric bypass, of which 79.6% were women. Overall, postoperative anemia was 28.9% (24.5% related to gastric bypass), especially among women (84%). Anemia refractory to oral iron therapy was observed in 12.9% of patients. All the patients requiring iron infusions (n = 54) were women, and half of them (51.8%) reported abnormal uterine bleeding. Postsurgical hemogram values were significantly lower in patients with abnormal uterine bleeding (despite the same number of infusions) than in those without gynecological disorders; 89.2% of these women had preoperative anemia.

CONCLUSION

Anemia is frequent in bariatric surgery patients despite supplementation. Women undergoing gastric bypass with a history of gynecological disorders are prone to require more iron infusions. Consulting with the patient about a higher risk is important, and probably knowing the plan or including the opinion of an OBGYN to determine as a team the assessment, treatment, and prognosis.

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.

Which nutritional prognosis is better? comparison of the three most commonly performed bariatric surgeries: A systematic review and network meta-analysis

Background

Obesity is one of the most important public health conditions in the world, and surgical intervention is the only medical treatment recognized by the medical community as a complete and permanent cure for morbid obesity and its complications. The choice of surgical modality is also based more on the experience of the physician or the requirements of people with obesity, rather than on scientific data. In this issue, a thorough comparison of the nutritional deficiencies caused by the three most commonly used surgical modalities is needed.

Objectives

We aimed to use the network meta-analysis to compare the nutritional deficiencies caused by the three most common BS procedures in many subjects who underwent BS to help physicians determine the best BS surgical approach to apply to their clinical people with obesity.

Setting

A systematic review and network meta-analysis of world literature.

Methods

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, systematically reviewed the literature, and conducted a network meta-analysis using R Studio.

Results

For the four vitamins calcium, vitamin B12, iron and vitamin D, the micronutrient deficiency caused by RYGB is the most serious.

Conclusions

RYGB causes slightly higher nutritional deficiencies in Bariatric surgery, but RYGB remains the most commonly used modality for Bariatric surgery.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022351956, identifier: CRD42022351956.

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.

Inadequacy of Vitamin D Does Not Interfere with Body Weight Loss in Women of Reproductive Age after Roux-en-Y Gastric Bypass

Objective: To assess the influence of vitamin D on body weight loss in women who had previously undergone Roux-en-Y gastric bypass (RYGB). Methodology: This is an analytical, longitudinal and retrospective study comprising 40 women of reproductive age who had previously undergone RYGB. To investigate the influence of the serum concentrations of vitamin D on body weight reduction, the variables were analyzed in the pre-operative period (T0), in the first (T1) and in the second postoperative year (T2) and were stratified according to the BMI measured in T1 and T2. In addition, in the pre-operative period, participants were subdivided into groups based on adequacy (G1), deficiency (G2) and insufficiency (G3), according to their serum concentrations of vitamin D. Results: Although weight loss occurred in a substantial way in T1, it continued to decrease in T2 (p = 0.017). The women who reached normal weight within two years of surgery showed the lowest vitamin D concentrations preoperatively when compared to those who were overweight (p = 0.011). Women with preoperative vitamin D deficiency showed increased concentrations in the assessed times (p < 0.001), while the opposite (p = 0.001) occurred in women with adequacy. Conclusion: The study showed that inadequacy of vitamin D does not interfere with weight loss in the two-year-follow-up after RYGB and highlights that vitamin D can present a differentiated response postoperatively, to the detriment of the pre-operative period.

Investigating the prevalence of nutritional abnormalities in patients prior to and following bariatric surgery

AIMS

Bariatric surgery remains an effective treatment for the condition of obesity. However it predisposes patients to nutritional deficiencies and related complications. The aim of this study was to identify nutritional abnormalities, weight loss, adherence to supplements, and presence of gastrointestinal symptoms in a cohort of bariatric surgical patients.

METHODS

An analysis of the electronic medical records of patients attending a multidisciplinary private clinic in Sydney, Australia from August 2020 to August 2021 was conducted. Data on anthropometric measures, nutritional indices, adherence to supplements and gastrointestinal symptoms preoperatively and then at ≤6 months, 1 and 2 years or more postoperatively were collected.

RESULTS

A total of 231 patients were included in the study. The majority of patients were female (76.2%), with a sleeve gastrectomy (78.8%). Average preoperative BMI was 43.4 ± 7.1 kg/m² . Weight loss ≥2 years postsurgery was 33.5 ± 12.4 kg. The most common abnormalities preoperatively were: C-reactive protein (47.7%), vitamin D (39%), B₁₂ (31%), parathyroid hormone (27.6%) and ferritin (12.7%). Vitamin B₁₂ (23.2%), parathyroid hormone (23%), vitamin D (17.7%) and ferritin (15.9%) remained common abnormalities postoperatively. Adherence to multivitamins was 90% in the first year following surgery, declining to 77% at ≥2 years. Gastrointestinal symptoms were predominantly present in the initial stages following surgery, manifesting thiamin deficiency in 6.5% of patients.

CONCLUSIONS

Despite achieving durable weight loss, nutritional and related abnormalities remain an ongoing challenge for bariatric surgery. Adherence to nutrient supplements, gastrointestinal symptoms and related complications are important considerations in addressing the problem.

Changes in the Bone Mineral Density after Sleeve Gastrectomy vs. Roux-En-Y Gastric Bypass 2 Years after Surgery

The aim of this study was to compare the analytical and densitometric changes 2 years after Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). A retrospective study of a prospectively collected database was performed. Morbidly obese patients undergoing RYGB or SG, as primary bariatric procedures, were included. Weight loss; analytical levels of parathormone (PTH), vitamin D, and calcium; and densitometric parameters were investigated. In total, 650 patients were included in the study, and 523 patients (80.5%) underwent RYGB and 127 (19.5%) SG. There were no significant differences in excess weight loss at 24 months between both groups. When comparing preoperative and postoperative values, a significantly greater increase in PTH values was observed in the RYGB group, whereas there were no significant differences in calcium and vitamin D levels. The mean t-score values decreased after surgery at all the locations and in both groups. The reduction in the t-score was significantly greater in the RYGB group at the femoral trochanter and lumbar spine. A decrease in bone mineral density (BMD) was observed after both techniques. The mean BMD decrease was significantly greater in the femoral trochanter and lumbar spine after RYGB.

The Effect of Vitamin D Supplementation on Serum 25-Hydroxy Vitamin D in the Patients Undergoing Bariatric Surgery: a Systematic Review and Meta-Analysis of Randomized Clinical Trials

Currently, there is no consensus on the optimal vitamin D administration in bariatric patients. The present systematic review and meta-analysis were conducted to examine the effect of vitamin D supplements on serum level of 25(OH) vitamin D in the patients undergoing bariatric surgery (BS).Random model effects were used to estimate standardized mean difference (SMD) with a 95% confidence interval (CI). Nine clinical trials were included in the meta-analysis. Vitamin D supplementation in patients undergoing BS modestly improves vitamin D status (SMD, 0.53; 95% CI, 0.28, 0.77) particularly, in the dosages above 2850 IU/day and in the patients with BMI greater than 50 kg/m². Vitamin D supplementation was associated with prevention of raising of the PTH serum concentration and without impact on serum calcium levels.

Impact of Bariatric Surgery-Induced Weight Loss on Anterior Eye Health in Patients with Obesity

The aim of the present research was to assess the effect of bariatric surgery-induced weight loss on the tear film and ocular surface of patients with obesity. A total of 29 participants with obesity (aged 47.2 ± 10.1 years, 8 male) were measured at baseline and followed up one year after Roux-en-Y gastric bypass (RYGB) surgery. General anthropometric data, as well as serum lipid markers of cholesterol, were assessed in all individuals. Bilateral anterior eye measurements of tear meniscus height (TMH), non-invasive tear breakup time, bulbar and limbal redness and infrared meibography were captured using the Keratograph K5M (Oculus) and ocular surface damage was evaluated using fluorescein sodium and lissamine green staining. Bariatric surgery resulted in significant loss of weight (body mass index p < 0.001) and an improvement in the blood lipid profile (p < 0.01) in all participants. However, there were no statistically significant differences between the baseline and one-year follow-up for any of the measured clinical ocular surface and tear film variables (all p > 0.05). Although there were trends for a reduced TMH and a decrease in meibomian gland dropout after bariatric surgery, these differences were also insignificant (p > 0.05). In conclusion, weight reduction through bariatric surgery did not have an effect on the tear film or ocular surface in unselected patients with obesity.

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.

Changes in Nutritional Outcomes After Sleeve Gastrectomy: a Systematic Review and Meta-analysis

PURPOSE

The aim of this meta-analysis is to evaluate the changes in nutritional indicators in individuals with obesity before and after SG.

MATERIALS AND METHODS

A systematic retrieval of the available literature was performed using PubMed, Embase, Web of Science, and Chinese National Knowledge Infrastructure databases. The following indicators were evaluated: serum 25-hydroxyvitamin D [25(OH)D], calcium, phosphorus, iron, vitamin B12, folate, magnesium, and zinc from pre-operation to post-operation.

RESULTS

A total of 38 studies met inclusion criteria. A significant increase was observed in serum 25(OH)D (SMD = 0.70, 95%CI 0.38 to 1.02, P < 0.001), phosphorus (SMD = 0.40, 95%CI 0.14 to 0.67, P = 0.003), iron (SMD = 0.50, 95%CI 0.38 to 0.62, P < 0.001), and folate (SMD = 0.37, 95%CI 0.09 to 0.65, P = 0.01) after SG. Nevertheless, the increasing trend of serum phosphorus (P = 0.143) and folate (P = 0.774) disappeared in the unprescribed subgroup. A significant decrease in serum zinc (SMD =  - 0.41, 95%CI - 0.81 to - 0.01, P = 0.044) was found after SG. No significant changes in serum calcium (SMD = 0.08, 95%CI - 0.09 to 0.25, P = 0.372), vitamin B12 (SMD = 0.10, 95%CI - 0.13 to 0.33, P = 0.398), and magnesium (SMD = 0.24, 95%CI - 0.10 to 0.58, P = 0.169) were observed. However, a significant decrease in serum calcium (P = 0.042) and vitamin B12 (P = 0.037) was found in the unprescribed subgroup.

CONCLUSIONS

Serum 25(OH)D, phosphorus, iron, and folate levels improved after a careful monitoring and due to a rigorous supplementation. The optimal dose of calcium, magnesium, and zinc supplementation has yet to be established; therefore, a broader supplementation of trace elements and minerals has to be suggested.

Long-term nutritional deficiencies following sleeve gastrectomy: a 6-year single-centre retrospective study

INTRODUCTION

Sleeve gastrectomy (SG) is associated with short-term nutritional deficiencies postoperatively. This study evaluates the long-term percentage of excess weight loss (% EWL), and nutritional deficiencies in a single-centre cohort undergoing SG as a primary procedure, with a 6-year follow-up.

MATERIAL AND METHODS

From January 2005 to December 2010 the records of 209 patients who underwent laparoscopic SG were retrieved from a computer database for analysis. Sixty out of the 209 paients completed follow-ups for 6 years.

RESULTS

Median % EWL at 1, 2, 3, 4, 5, and 6 years postoperatively was 80.9%, 79.1%, 73.8%, 71.8%, 71.5%, and 64.9%, respectively. Prior to surgery, 17.2% had anaemia. Deficiencies of iron, ferritin, folic acid, vitamin B₁₂, magnesium, and phosphorus were 22%, 5.3%, 1.4%, 3.8%, 29.7%, and 5.3%, respectively. Six years post-surgery, deficiencies of haemoglobin, ferritin, and B₁₂ worsened (36.7%, 43.3%, and 11.7%, p = 0.001, p < 0.001, p = 0.019, respectively), whereas there was no significant difference in deficiencies of iron, folic acid, magnesium, and phosphorus (25%, 1.7%, 20%, and 3%, p = 0.625, p = 0.896, p = 0.139, p = 0.539, respectively). There was elevated PTH before and 6 years after surgery (2.9% and 1.7%, p = 0.606).

CONCLUSIONS

This retrospective study shows that laparoscopic sleeve gastrectomy had a considerable effect on specific nutritional deficiencies in our patients at 6 years post-surgery. Knowledge of micronutrient deficiencies in these patients is beneficial for both prevention and management of nutritional complications associated with SG with the administration of oral nutritional supplementation according to the patient's needs.

Expert opinion on the preoperative medical optimization of adults with diabetes undergoing metabolic surgery

Diabetes mellitus (DM) and obesity are interrelated in a complex manner, and their coexistence predisposes patients to a plethora of medical problems. Metabolic surgery has evolved as a promising therapeutic option for both conditions. It is recommended that patients, particularly those of Asian origin, maintain a lower body mass index threshold in the presence of uncontrolled DM. However, several comorbidities often accompany these chronic diseases and need to be addressed for successful surgical outcome. Laparoscopic Roux-en-Y gastric bypass (RYGB) and laparoscopic sleeve gastrectomy (LSG) are the most commonly used bariatric procedures worldwide. The bariatric benefits of RYGB and LSG are similar, but emerging evidence indicates that RYGB is more effective than LSG in improving glycemic control and induces higher rates of long-term DM remission. Several scoring systems have been formulated that are utilized to predict the chances of remission. A glycemic target of glycated hemoglobin < 7% is a reasonable goal before surgery. Cardiovascular, pulmonary, gastrointestinal, hepatic, renal, endocrine, nutritional, and psychological optimization of surgical candidates improves perioperative and long-term outcomes. Various guidelines for preoperative care of individuals with obesity have been formulated, but very few specifically focus on the concerns arising from the presence of concomitant DM. It is hoped that this statement will lead to the standardization of presurgical management of individuals with DM undergoing metabolic surgery.

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.

A Review of Current Trends with Type 2 Diabetes Epidemiology, Aetiology, Pathogenesis, Treatments and Future Perspectives

Type 2 diabetes (T2D), which has currently become a global pandemic, is a metabolic disease largely characterised by impaired insulin secretion and action. Significant progress has been made in understanding T2D aetiology and pathogenesis, which is discussed in this review. Extrapancreatic pathology is also summarised, which demonstrates the highly multifactorial nature of T2D. Glucagon-like peptide (GLP)-1 is an incretin hormone responsible for augmenting insulin secretion from pancreatic beta-cells during the postprandial period. Given that native GLP-1 has a very short half-life, GLP-1 mimetics with a much longer half-life have been developed, which are currently an effective treatment option for T2D by enhancing insulin secretion in patients. Interestingly, there is continual emerging evidence that these therapies alleviate some of the post-diagnosis complications of T2D. Additionally, these therapies have been shown to induce weight loss in patients, suggesting they could be an alternative to bariatric surgery, a procedure associated with numerous complications. Current GLP-1-based therapies all act as orthosteric agonists for the GLP-1 receptor (GLP-1R). Interestingly, it has emerged that GLP-1R also has allosteric binding sites and agonists have been developed for these sites to test their therapeutic potential. Recent studies have also demonstrated the potential of bi- and tri-agonists, which target multiple hormonal receptors including GLP-1R, to more effectively treat T2D. Improved understanding of T2D aetiology/pathogenesis, coupled with the further elucidation of both GLP-1 activity/targets and GLP-1R mechanisms of activation via different agonists, will likely provide better insight into the therapeutic potential of GLP-1-based therapies to treat T2D.

A Pilot Study of Nutritional Status Prior to Bariatric Surgery in South China

Objective: The was a pilot study to assess the biochemical and historical information about bariatric patients before undergoing the surgery in the aim of identifying nutritional deficiencies and their prevalence from 2015 to 2020.

Methods: Clinical data of 247 patients (105 males and 142 females) were included. Vitamins, trace elements, electrolytes, albumin, globulin, hemoglobin, folate, ferritin, microalbuminuria (MAU), and parathyroid hormone (PTH) levels were determined to explore the nutritional status according to gender, age, high body mass index (BMI), and waist circumstance (WC).

Results: The mean age, mean BMI, and mean WC of the candidates were 32.95 ± 10.46 years, 38.01 ± 7.11 kg/m², and 117.04 ± 16.18 cm, respectively. The prevalence of preoperative nutritional deficiencies was 76.88% for 25 (OH) vitamin D, 19.84% for globulin, 11.74% for albumin, 11.02% for sodium, 8.33% for folic acid, 10.48% (male) and 6.34% (female) for chloride, 4.05% for calcium, 3.07% (male) and 0.70%(female) for ferritin, 11.90% for elevated PTH, and 44.96% for MAU. Males exhibited increased prevalence of globulin and MAU relative to females (P < 0.05). Older groups are more likely to exhibit albumin deficiency (P = 0.007), globulin deficiency (P = 0.003), and zinc deficiency (P = 0.015). In addition, 25 (OH) D deficiency and albumin deficiency were more common in patients with BMI ≥ 47.5 kg/m² (P = 0.049 and 0.015, respectively). Wider WC (≥150 cm) exhibited higher rates of albumin deficiencies (P = 0.011).

Conclusion: Electrolyte and nutritional deficiencies were common in patients prior to bariatric surgery in South China. Routine evaluation of electrolyte and nutritional levels should be carried out in this population.

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.

Pre-operative micronutrient deficiencies in patients with severe obesity candidates for bariatric surgery

PURPOSE

In patients with obesity, micronutrient deficiencies have been reported both before and after bariatric surgery (BS). Obesity is a chronic pro-inflammatory status, and inflammation increases the risk of micronutrient malnutrition. Our objective was to assess in pre-BS patients the prevalence of micronutrient deficiencies and their correlation with blood values of C-reactive protein (CRP).

METHODS

Anthropometric data, instrumental examinations, and blood variables were centrally measured in the first 200 patients undergoing a pre-BS evaluation at the "Città della Salute e della Scienza" Hospital of Torino, starting from January 2018.

RESULTS

At least one micronutrient deficiency was present in 85.5% of pre-BS patients. Vitamin D deficiency was the most prevalent (74.5%), followed by folate (33.5%), iron (32%), calcium (13%), vitamin B12 (10%), and albumin (5.5%) deficiency. CRP values were high (> 5 mg/L) in 65% of the patients. These individuals showed increased rate of iron, folate, vitamin B12 deficiency, and a higher number of micronutrient deficiencies. In a multiple logistic regression model, increased CRP levels were significantly associated with deficiencies of vitamin B12 (OR = 5.84; 95% CI 1.25-27.2; p = 0.024), folate (OR = 4.02; 1.87-8.66; p < 0.001), and with the presence of ≥ 2 micronutrient deficiencies (OR = 2.31; 1.21-4.42; p = 0.01).

CONCLUSIONS

Micronutrient deficiencies are common in patients with severe obesity undergoing BS, especially when inflammation is present. In the presence of increased CRP values before surgery, it might be advisable to search for possible multiple micronutrient deficiencies.

Iron deficiency is highly prevalent among candidates for metabolic surgery and may affect perioperative outcomes

BACKGROUND

The presence of chronic low-grade inflammation, commonly identified in patients with severe obesity, alters iron homeostasis and indicators of iron status, fostering the development of updated guidelines for the diagnosis of iron deficiency (ID). Current recommended diagnostic thresholds for ID in obesity derived from expert opinion include a ferritin level of <30 ng/mL and/or transferrin saturation (TSAT) < 20%. Earlier studies of ID among candidates for metabolic surgery using low levels of ferritin or iron as diagnostic thresholds demonstrated a prevalence of 5%-20%.

OBJECTIVES

Using the current recommended diagnostic thresholds for ID, this study measures the prevalence of ID in a large cohort of surgical candidates and its relationship to surgical outcomes.

SETTING

Geisinger Medical Center, Danville, Pennsylvania.

METHODS

The study cohort included 3,723 patients who underwent pre- operative nutritional assessment which included markers of iron nutrition over the period 2004-2018.

RESULTS

The cohort included 2,988 women (80.3%) and 735 men (19.7%); body mass index: 49.4 ± 9 kg/m². The diagnosis of ID was based on ferritin level <30 ng/mL (true ID) and/or TSAT < 20% representing a combination of true ID and inflammation (serum ferritin ≥ 30 ng/mL and TSAT < 20%). A total of 399 patients (10.8%) were anemic. A serum ferritin level of < 30 ng/mL was found in 488 patients (13%; 481 women and 7 men). Of these, 122 patients (25.2%) were also anemic. An additional 1,204 had serum ferritin ≥ 30 ng/mL and TSAT < 20%. Overall, 1,692 patients (45.4%) in this cohort had laboratory evidence of ID by current criteria that adjusts for the very high prevalence of inflammation. Men with serum ferritin levels ≥30 ng/mL with TSAT < 20% had an increased surgical length of stay.

CONCLUSION

The prevalence of ID among surgical candidates (45.4%) is more than twice that identified as ID in earlier studies. ID was commonly identified in the absence of anemia. The most severe ID was found in those with a serum ferritin level <30 ng/mL and TSAT < 20%. ID in the presence of inflammation is often unrecognized and has implications regarding surgical outcomes after metabolic surgery.

Nutritional Assessment and Preparation for Adult Bariatric Surgery Candidates: Clinical Practice

Bariatric surgery (BS) has proven to be highly efficacious in the treatment of obesity and its comorbidities. However, careful patient selection is critical for its success. Thus, patients should undergo medical, behavioral, and nutritional assessment by a multidisciplinary team. From the nutritional point of view, BS candidates should undergo nutritional assessment, preparation, and education by a registered dietitian in the preoperative period. Currently, detailed specified and comprehensive information on these topics is lacking. The present narrative review aimed to summarize the available literature concerning both the preoperative nutritional assessment components and the preoperative nutritional preparation and education components of patients planning to undergo BS. Current literature indicates that proper management before BS should include a comprehensive nutritional assessment, in which it is advisable to perform a clinical interview to assess patients' medical background, weight management history, eating patterns and pathologies, oral health, physical activity habits, nutritional status, supplementation usage, BS knowledge, surgery expectations and anthropometric measurements. Nutritional preparation and educational strategies should include an individualized preoperative weight-loss nutrition program, improvement of glycemic control, micronutrients deficiencies correction, eating and lifestyle habits adaptation, physical activity initiation, and strengthening knowledge on obesity and BS. At this stage, more well-designed intervention and long-term cohort studies are needed in order to formulate uniform evidence-based nutritional guidelines for patients who plan to undergo BS, including populations at higher nutritional risk. Moreover, postoperative outcomes of presurgical nutritional intervention programs should be studied.

Alterations of bone markers in obese patients with type 2 diabetes after bariatric surgery: A meta-analysis and systemic review of randomized controlled trials and cohorts

BACKGROUND

The aim of this study is to evaluate the alterations in bone mineral density and other surrogate markers for osteoporosis in obese patients with type 2 diabetes mellitus (T2DM) who received Roux-en-Y gastric bypass (RYGB) versus medical treatment as control.

METHODS

We searched 4 electronic databases and reference lists of relevant studies for eligible research published before December, 2019. After quality assessment, eligible studies were synthesized for relevant outcomes, including lumbar spine bone mineral density (L-spine BMD) change, total hip BMD change, osteocalcin level, C-terminal telopeptide level, and parathyroid hormone level.

RESULTS

Three randomized clinical trials and 2 observational studies concerning 307 total obese T2DM patients were included. Follow-up ranged from 12 to 60 months. Patients underwent RYGB surgery were associated with both higher L-spine BMD loss (mean difference: -2.90, 95% CI: -2.99∼-2.81, P < .00001) and total hip BMD loss (mean difference: -5.81, 95% CI: -9.22∼-2.40, P = .0008). As to biochemical markers of bone metabolism, we found significantly higher osteocalcin level in medical treatment (control) group compared with RYGB group (mean difference: 11.16, 95% CI: 8.57-13.75, P < .00001). However, higher C-terminal telopeptide level and parathyroid hormone level were noted in medical treatment group (control) compared with RYGB group (mean difference: 0.29, 95% CI: 0.11-0.48, P = .002; mean difference: 1.56, 95% CI: 0.84-2.27, P < .0001).

CONCLUSIONS

RYGB surgery is associated with negative impact on bone metabolism and increase the risk of osteoporosis in obese patients with T2DM. We suggest that clinicians acknowledge the adverse effects of surgery and keep monitoring bone mineral components in post-RYGB populations. Further studies regarding the optimal amount of perioperative and postsurgical supplementation should be evaluated.

Combined ASBT Inhibitor and FGF15 Treatment Improves Therapeutic Efficacy in Experimental Nonalcoholic Steatohepatitis

BACKGROUND & AIMS

Pharmacologic agents targeting bile acid signaling show promise for treating nonalcoholic steatohepatitis (NASH). However, clinical findings suggest that new treatment strategies with enhanced therapeutic efficacy and minimized undesired effects are needed. This preclinical study investigates whether combining an apical sodium-bile acid transporter (ASBT) inhibitor GSK233072 (GSK672) and fibroblast growth factor-15 (FGF15) signaling activation improves anti-NASH efficacy.

METHODS

Mice with high fat, cholesterol, and fructose (HFCFr) diet-induced NASH and stage 2 fibrosis are used as a NASH model. GSK672 or AAV8-TBG-FGF15 interventions are administered alone or in combination to HFCFr diet-fed mice.

RESULTS

The combined treatment significantly enhances therapeutic efficacy against steatosis, inflammation, ballooning, and fibrosis than either single treatment. Mechanistically, the synergistic actions of GSK672 and FGF15 on inhibiting gut bile acid reuptake and hepatic bile acid synthesis achieve greater magnitude of bile acid pool reduction that not only decreases bile acid burden in NASH livers but also limits intestinal lipid absorption, which, together with FGF15 signaling activation, produces weight loss, reduction of adipose inflammation, and attenuated hepatocellular organelle stress. Furthermore, the combined treatment attenuates increased fecal bile acid excretion and repressed bile acid synthesis, which underlie diarrhea and hypercholesterolemia associated with ASBT inhibition and FGF19 analogue, respectively, in clinical settings.

CONCLUSIONS

Concomitant ASBT inhibition and FGF15 signaling activation produce metabolic changes that partially mimic the bariatric surgery condition whereby lipid malabsorption and increased FGF15/19 signaling synergistically mediate weight loss and metabolic improvement. Further clinical studies may be warranted to investigate whether combining ASBT inhibitor and FGF19 analogue enhances anti-NASH efficacy and reduced treatment-associated adverse events in humans.

Iron Deficiency in Obesity and after Bariatric Surgery

Iron deficiency (ID) is particularly frequent in obese patients due to increased circulating levels of acute-phase reactant hepcidin and adiposity-associated inflammation. Inflammation in obese subjects is closely related to ID. It induces reduced iron absorption correlated to the inhibition of duodenal ferroportin expression, parallel to the increased concentrations of hepcidin. Obese subjects often get decreased inflammatory response after bariatric surgery, accompanied by decreased serum hepcidin and therefore improved iron absorption. Bariatric surgery can induce the mitigation or resolution of obesity-associated complications, such as hypertension, insulin resistance, diabetes mellitus, and hyperlipidemia, adjusting many parameters in the metabolism. However, gastric bypass surgery and sleeve gastrectomy can induce malabsorption and may accentuate ID. The present review explores the burden and characteristics of ID and anemia in obese patients after bariatric surgery, accounting for gastric bypass technique (Roux-en-Y gastric bypass-RYGB) and sleeve gastrectomy (SG). After bariatric surgery, obese subjects' iron status should be monitored, and they should be motivated to use adequate and recommended iron supplementation.

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.

The Relationship Between Bariatric Surgery and Diet Quality: a Systematic Review

BACKGROUND

Bariatric surgery is currently the most effective treatment for morbid obesity. These procedures change the gastrointestinal system with the aim of reducing dietary intake. Improving diet quality is essential in maintaining nutritional health and achieving long-term benefits from the surgery. The aim of this systematic review was to examine the relationship between bariatric surgery and diet quality at least 1 year after surgery.

METHODS

A systematic search of five databases was conducted. Studies were included that reported diet quality, eating pattern, or quality of eating in adult patients who had undergone laparoscopic-adjusted gastric banding (LAGB), Roux-en-Y gastric bypass (RYGB), and sleeve gastrectomy (SG) procedures. Data was extracted to determine the relationship between having had bariatric surgery and subsequent diet quality.

RESULTS

A total of 34 study articles (described in 36 articles) met the inclusion criteria. The majority of studies were observational in nature and showed a reduction in energy intake following surgery, as well as inadequate intakes of micronutrients and protein, and an excessive intake of fats. There was evidence of nutrient imbalances, suboptimal compliance with multivitamin and mineral supplementation, and limited follow-up of patients.

CONCLUSION

The current evidence base suggests that despite being effective in reducing energy intake, bariatric surgery can result in unbalanced diets, inadequate micronutrient and protein intakes, and excessive intakes of fats. In combination with suboptimal adherence to multivitamin and mineral supplementation, this may contribute to nutritional deficiencies and weight regain. There is a need for high-quality nutrition studies, to identify optimal dietary compositions following bariatric surgery.

Nutrient Intake and Deficiency of Patients 1 Year After Bariatric Surgery: Tehran Obesity Treatment Study (TOTS)

PURPOSE

This study aimed at assessing nutrient adequacy after 1 year in patients who had undergone gastric bypass (GB) surgery or sleeve gastrectomy (SG) and to investigate the association of nutrient adequacy with anthropometric indices.

METHODS

A total of 180 severely obese patients (BMI ≥ 35 kg/m²) were selected among the participants of Tehran Obesity Treatment Study. Nutritional assessments were performed over 3 days of 24-h dietary recall. To evaluate the nutrient adequacy ratio (NAR), the subject's nutrient intake was divided by the dietary reference intakes. The mean adequacy ratio (MAR) was also determined as the sum of NARs divided by the number of involved nutrients (n = 11).

RESULTS

The mean age of SG (67%) and GB (32%) patients was 39.2 ± 12 and 41.4 ± 10 years, respectively. SG patients had more postoperative fat-free mass (52.0 ± 12 kg) than GB patients (49.7 ± 8 kg) (P < 0.05). The most common postoperative serum nutrient deficiencies were related to vitamin B12 (30%), ferritin (19%), and 25-hydroxyvitamin D (16.2%). Moreover, high inadequacy of protein (> 80%) and total fat (> 70%) intake was reported. The MAR score showed that almost 45% of the patients had possibly adequate intakes of some nutrients. The adequacy of nutrients was positively associated with fat-free mass (β = 8.67, P < 0.05).

CONCLUSION

These findings revealed that patients had inadequate nutrient intakes 1 year after bariatric surgery, which was accompanied by serum nutritional deficiencies. Compared to GB patients, SG patients had a better body composition. Overall, compliance of patients with dietary guidelines and supplementations needs to be carefully monitored in the postoperative period.

The effect of iron deficiency and anaemia on women's health

Iron deficiency and anaemia are global health problems and major causes of morbidity in women. Current definitions of anaemia in women are historic and have been challenged by recent data from observational studies. Menstrual loss, abnormal uterine bleeding and pregnancy put women at risk of developing iron deficiency which can result in severe fatigue, reduced exercise capacity and poor work performance. Iron deficiency and anaemia during pregnancy are associated with adverse maternal and fetal outcomes, including neurocognitive deficits in children born to iron-deficient mothers. Both iron deficiency and anaemia are common in women undergoing surgery but their association with poor outcomes remains uncertain. The enduring burden of iron deficiency and anaemia in women suggests that current strategies for recognition, prevention and treatment are limited in their utility. Improvements in our understanding of iron homeostasis and the development of new iron preparations, which are better absorbed with fewer side-effects, may improve therapeutic effectiveness of oral iron. Intravenous iron is efficacious for correcting anaemia rapidly but high-quality data on patient-centred outcomes and cost-effectiveness are currently lacking. Many recommendations for the treatment of iron deficiency and anaemia in national guidelines are not supported by high-quality evidence. There is a need for robust epidemiological data and well-designed clinical trials. The latter will require collaborative working between researchers and patients to design studies in ways that incorporate patients' perspectives on the research process and target outcomes that matter to them.

Changes in Anthropometric Measures, Nutritional Indices and Gastrointestinal Symptoms Following One Anastomosis Gastric Bypass (OAGB) Compared with Roux-en-y Gastric Bypass (RYGB)

Purpose

Bariatric surgery is an effective treatment for obesity with new procedures emerging. However, despite comparable weight loss and improvements in metabolic outcomes, research on nutritional and gastrointestinal symptoms remains limited. Here we compare clinical data on weight, nutritional disorders and gastrointestinal symptoms of patients before and following one anastomosis gastric bypass (OAGB) and Roux-en-Y gastric Bypass (RYGB).

Materials and Methods

In this retrospective study, data on anthropometry, nutritional indices, dietary intake and gastrointestinal symptoms were retrieved in cohorts of patients up to 2 years following OAGB and RYGB.

Results

Seventy-three patients had either a RYGB (28) or an OAGB (45), with 71% seeking these as a revisional procedure. Significant and higher weight loss was observed in the OAGB cohort at 1 year (%TWL 33.0 ± 8.5 vs. 26.6 ± 12.4), albeit comparable at 2 years postoperatively (%TWL 29.0 ± 11.1 vs. 34.1 ± 11.2). Disorders such as vitamin D, active B12, folate, homocystein (Hcy) and hyperparathyroidism were present following both surgeries. Levels of vitamin D, ferritin and total protein significantly worsened over time. Gastrointestinal symptoms of diarrhoea, steatorrhoea and reflux were higher in the OAGB cohort while the RYGB cohort reported more dumping syndrome (DS).

Conclusion

Significant and similar weight loss results are seen following both OAGB and RYGB. Nutritional disorders were common in both cohorts and increased over time. However, the OAGB patients reported more gastrointestinal side effects, which may contribute to poor quality of life and nutritional consequences. Prospective and longer-term studies investigating the nutritional and gastrointestinal health of patients undergoing OAGB is recommended.

Laparoscopic Vertical Sleeve Gastrectomy as a Treatment Option for Adults with Diabetes Mellitus

Obesity is a major factor in the worldwide rise in the prevalence of type 2 diabetes mellitus. The obesity "epidemic" will require novel, effective interventions to permit both the prevention and treatment of diabetes caused by obesity. Laparoscopic vertical sleeve gastrectomy is a newer bariatric surgical procedure with a lower risk of complications (compared to Roux-en-Y gastric bypass surgery). Based in part on restriction of daily caloric intake, sleeve gastrectomy has a major role in inducing significant weight loss and weight loss is maintained for at least 10 years. Prior studies have supported the utility of the vertical sleeve gastrectomy for the treatment and management of subgroups of individuals with diabetes mellitus. There are reports of 11% to 76.9% of obese individuals discontinuing use of diabetic medications in studies lasting up to 8 years after vertical sleeve gastrectomy. Major ongoing issues include the preoperative determination of the suitability of diabetic patients to undergo this bariatric surgical procedure. Understanding how this surgical procedure is performed and the resulting anatomy is important when vertical sleeve gastrectomy is being considered as a treatment option for diabetes. In the postoperative periods, specific macronutrient goals and micronutrient supplements are important for successful and safer clinical results. An understanding of immediate- and long term- potential complications is important for reducing the potential risks of vertical sleeve gastrectomy. This includes the recognition and treatment of postoperative nutritional deficiencies and disorders. Vertical sleeve gastrectomy is a component of a long term, organized program directed at treating diabetes related to obesity. This approach may result in improved patient outcomes when vertical sleeve gastrectomy is performed to treat type 2 diabetes in obese individuals.

A Prospective Study of Association of Micronutrients Deficiencies during Pregnancy and Neonatal Outcome among Women after Bariatric Surgery

Little is known about the association of micronutrients deficiencies during pregnancy and neonatal outcome among women after Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). We present a prospective study of 87 consecutive women with a history of RYGB (n = 37) or SG (n = 50) who underwent complete and regular clinical and biological nutritional assessments during pregnancy. Data on maternal characteristics, biological nutritional parameters, antenatal management, and perinatal outcome were collected. The objective was to evaluate serum levels of micronutrients at the second trimester, and to assess the association between micronutrients deficiencies and neonatal outcome. After RYGB, maternal age (34.3 ± 4.9 vs. 31.1 ± 4.6 years; p = 0.003) and pregnancy timing after surgery (64.5 ± 47.0 vs. 38.1 ± 28.1 months; p = 0.002) were significantly higher, and pre-pregnancy BMI was significantly lower (29.8 ± 5.6 vs. 32.9 ± 7.1 kg/m2; p = 0.03). Maternal and neonatal outcomes were similar. Additional supplementations after blood tests were similar in groups. Zinc, selenium, vitamins A1, B1, B6, C, and E levels were not different depending on the type of surgery. Zinc deficiency (7/87) was significantly more frequent after RYGP (18.9% vs. 0%; p = 0.02) and selenium deficiency (15/87) was similar in groups (21.6% after RYGB and 14.0% after SG; p = 0.36). The mean birth weight was significantly lower in selenium deficiency cases (3137 ± 550 vs. 3535 ± 737 g; p = 0.04). Selenium deficiency was negatively correlated with birth weight (r = -0.23; p = 0.03) and with birth weight z-score (r = -0.26; p = 0.01), but not correlated after adjustment for the procedure. The levels of micronutrients surveillance along pregnancy in women with a history of bariatric surgery is necessary to decrease the risk of inadequate fetal growth in the patients.

Current treatment paradigms and emerging therapies for NAFLD/NASH

Non-alcoholic fatty liver disease (NAFLD) is one the fastest emerging manifestations of the metabolic syndrome worldwide. Non-alcoholic steatohepatitis (NASH), the progressive form of NAFLD, may culminate into cirrhosis and hepatocellular cancer (HCC) and is presently a leading cause of liver transplant. Although a steady progress is seen in understanding of the disease epidemiology, pathogenesis and identifying therapeutic targets, the slowest advancement is seen in the therapeutic field. Currently, there is no FDA approved therapy for this disease and appropriate therapeutic targets are urgently warranted. In this review we discuss the role of lifestyle intervention, pharmacological agents, surgical approaches, and gut microbiome, with regard to therapy for NASH. In particular, we focus the role of insulin sensitizers, thyroid hormone mimetics, antioxidants, cholesterol lowering drugs, incretins and cytokines as therapeutic targets for NASH. We highlight these targets aiming to optimize the future for NASH therapy.

Continuous glucose monitoring in patients with remission of type 2 diabetes after laparoscopic sleeve gastrectomy without or with duodenojejunal bypass

Bariatric surgery is associated with a high remission rate of type 2 diabetes mellitus. However, it is unclear whether patients showing remission of diabetes actually have normal blood glucose levels throughout the day. We therefore performed continuous glucose monitoring (CGM) in 15 ambulatory patients showing remission of diabetes after laparoscopic sleeve gastrectomy (LSG) without or with duodenojejunal bypass (DJB) at the time of diabetic remission (12.9 ± 1.8 months after bariatric surgery). The definition of remission of diabetes was based on the American Diabetes Association criteria. The mean, SD, and coefficient of variation (CV) of glucose calculated from CGM were 6.2 ± 0.6 mmol/L, 1.5 ± 0.4 mmol/L, and 23.7 ± 6.2%, respectively. These values were higher than those of healthy participants without diabetes previously reported. The percentages of time spent above 10.0 mmol/L and below 3.9 mmol/L were 2.6 (IQR 0-5.0)% and 0 (IQR 0-8.0)%, respectively. Thus, patients with remission of diabetes after LSG or LSG/DJB still had substantial periods of hyperglycemia and hypoglycemia throughout the day. Therefore, we must manage patients with diabetes carefully, even after apparent remission of type 2 diabetes in response to bariatric surgery.

New concepts in the diagnosis and management approach to iron deficiency in candidates for metabolic surgery: should we change our practice?

The near universal presence of chronic low-grade systemic inflammation among patients with severe obesity disrupts iron homeostasis and underlies the association between obesity and iron deficiency. Immune activation and inflammation result in a reduction in circulating iron and diminished iron bioavailability for erythropoiesis. Inflammation also alters blood levels of commonly measured markers of iron nutrition status, which makes the diagnosis of iron deficiency difficult and has led to new recommendations regarding laboratory markers for the diagnosis. Recent evidence using these newly recommended laboratory markers, which include levels of ferritin, C-reactive protein, and transferrin saturation, suggests that the actual prevalence of iron deficiency among candidates for metabolic surgery may be double or triple the prevalence identified by low levels of ferritin alone. Thus large numbers of surgical candidates have iron deficiency that has been heretofore largely unrecognized and inadequately treated. The assessment of iron status using the currently recommended markers in the presence of chronic inflammatory diseases and repletion of depleted stores for surgical candidates with deficiency during the preoperative period present an important opportunity for mitigating this condition in postoperative patients.

Immunometabolism, Micronutrients, and Bariatric Surgery: The Use of Transcriptomics and Microbiota-Targeted Therapies

BACKGROUND

Obesity is associated with the gut microbiota and decreased micronutrient status. Bariatric surgery is a recommended therapy for obesity. It can positively affect the composition of the gut bacteria but also disrupt absorption of nutrients. Low levels of micronutrients can affect metabolic processes, like glycolysis, TCA cycle, and oxidative phosphorylation, that are associated with the immune system also known as immunometabolism.

METHODS

MEDLINE, PUBMED, and Google Scholar were searched. Articles involving gut microbiome, micronutrient deficiency, gut-targeted therapies, transcriptome analysis, micronutrient supplementation, and bariatric surgery were included.

RESULTS

Studies show that micronutrients play a pivotal role in the intestinal immune system and regulating immunometabolism. Research demonstrates that gut-targeting therapies may improve the microbiome health for bariatric surgery populations. There is limited research that examines the role of micronutrients in modulating the gut microbiota among the bariatric surgery population.

CONCLUSIONS

Investigations are needed to understand the influence that micronutrient deficiencies have on the gut, particularly immunometabolism. Nutritional transcriptomics shows great potential in providing this type of analysis to develop gut-modulating therapies as well as more personalized nutrition recommendations for bariatric surgery patients.

Obesity population at risk of COVID-19 complications

Introduction

Global public health is challenged by two concurrent epidemics; COVID-19 and obesity. Considering the global prevalence of obesity, exploring relationships with COVID-19 are of clinical importance. The aim was to provide a comprehensive summary and recommendations on this relationship between COVID-19 and obesity.

Method

A literature search was performed to prepare a narrative review of COVID-19 and obesity.

Results

An obesity state promotes chronic inflammation, vitamin D deficiency, hinders immunity and causes mechanical lung compression. These increase susceptibilities to COVID-19 infection, complications including the requirement of invasive ventilation. Existing co-morbidities enhances these complications. Preventive measures of social distancing and self-isolation may increase stigmatisation and psychological deterrents. Hence, special recommendations targeting this vulnerable population are required.

Conclusion

The obese population is a COVID-19 vulnerable group, requiring special attention during this pandemic to avoid complications and healthcare systems burden. Lacking COVID-19 vaccination, regular physical activity and a healthy diet are recommended with attention to mental health. A prolonged quarantine duration and administration of prophylactic vitamin D may be considered.

Use of Home Enteral Nutrition in Malnourished Post-Bariatric Surgery Patients

BACKGROUND

Bariatric surgery is by far the most effective treatment option available for successfully achieving and maintaining weight loss in the obese population, but it can also be associated with complications that lead to malnutrition. There is limited data on how enteral nutrition (EN) can be used to provide nutrition support in such cases.

METHODS

Retrospective review of our Home Enteral Nutrition (HEN) database was conducted from February 2013 to April 2018 to identify patients who received HEN because of bariatric surgery-related complication.

RESULTS

During the study period, 72 patients (86% female, mean age 50.3 ± 11.6 years) initiated HEN because of bariatric surgical complication. Most common bariatric surgery was Roux-en-Y (74%) and most common indication for HEN was malnutrition/failure to thrive (33%). HEN was most commonly provided through nasojejunal feeds and resulted in an average increase in body weight and body mass index from 74.8 kg and 26.5, respectively, before HEN to 76.9 kg and 27.2, respectively, at the end of the HEN period. Through HEN, patients received 22.2 ± 7.9 kcal/kg/d and 1.0 ± 0.3 g/kg/d protein, meeting 94% ± 17% of their energy goals and 95% ± 29% of their protein goals. Vitamin deficiencies were noted in 69% of patients at the time of HEN initiation, which improved to 10% after enteral feeds and appropriate vitamin supplementation.

CONCLUSION

HEN is safe and effective in treating malnutrition and vitamin deficiencies that might occur as a complication of bariatric surgery, leading to avoidance of parenteral nutrition support in most cases.

Iron deficiency in bariatric surgery patients: a single-centre experience over 5 years

Background

As the prevalence of obesity has increased, so too has the demand for bariatric surgery. This study aimed to determine the incidence of postoperative iron deficiency and anemia and the impact of an increased preoperative ferritin target on postoperative outcomes.

Methods

Patients undergoing bariatric surgery in Winnipeg from 2010 to 2014 were included in the analysis. Data capture included age, sex and date of surgery and iron, ferritin and hemoglobin levels before surgery and 12 months postoperatively. Before 2014, there was no protocol for preoperative iron supplementation at our centre; in 2014, a more aggressive preoperative iron supplementation program was introduced to target a minimum preoperative ferritin level of 50 mg/L. Data were analyzed using unpaired t tests, paired t tests and χ2 tests.

Results

A total of 399 patients were considered; 288 were included in the analysis. The incidence of iron and ferritin deficiency and anemia at 12 months postoperatively was 14.6%, 9.3% and 15.0%, respectively. In patients who underwent surgery before 2014, the 12-month postoperative levels of iron and ferritin were 12.9 mmol/L and 64.0 mg/L, respectively; patients who underwent surgery in 2014 had levels of 18.3 mmol/L and 124.0 mg/L, respectively (all p = 0.001). The 12-month postoperative hemoglobin levels did not significantly differ between the 2 groups.

Conclusion

Bariatric surgery performed with more aggressive preoperative iron supplementation is associated with increased iron and ferritin levels at 1 year postoperatively. As this improves overall clinical outcomes by avoiding iron deficiency and anemia, a minimum preoperative ferritin target should be implemented in metabolic and bariatric surgery programs.