The True Story on Deficiencies After Sleeve Gastrectomy: Results of a Double-Blind RCT

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

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

Bone health following paediatric and adolescent bariatric surgery: a systematic review and meta-analysis

Background

Childhood obesity is a pressing health crisis of epidemic proportions. Bariatric surgery (BS) is an effective weight loss solution however its role in the paediatric population is contentious owing to the paucity of weight specific and generalised health outcomes. This systematic review and meta-analysis aimed to assess the impact of paediatric BS on bone health.

Methods

This prospectively registered systematic review (PROSPERO ID: CRD42023432035) was performed in accordance with PRISMA guidelines. We searched MEDLINE (1946-1928 September 2023), EMBASE (1947-1928 September 2023) via the Ovid platform, and the Cochrane Review Library to identify scientific publications reporting bone outcome measures in patients under the age of 18 years who underwent BS. Meta-analysis was undertaken on post-operative weight and bone parameters in paediatric patients following BS. Outcomes were reported as weighted or standardized mean difference with 95 percent confidence intervals. Subgroup analysis by intervention, quality scoring and risk of bias were assessed.

Findings

Twelve studies with 681 patients across 5 countries (mean age 17 ± 0.57 years) were included. The quality of included studies was rated as high and there was substantial between-study heterogeneity for most factors included in the meta-analysis (I2 from 0% to 99.1%). Patients underwent Roux-en-Y gastric bypass (RYGB, n = 216), sleeve gastrectomy (SG, n = 257), gastric band (n = 184) or intragastric balloon placement (n = 24). BS was associated with significant weight reduction, body mass index (BMI) -12.7 kg/m2 (95% CI -14.5 to -10.9, p < 0.001), with RYGB being most effective, BMI -16.58 kg/m2 (95% CI -19.6 to -13.6, p < 0.001). Patients who underwent SG or RYGB had significantly lower lumbar bone mineral density, -0.96 g/cm2 (95% CI -0.1 to -0.03, p < 0.001), Z score, -1.132 (95% CI -1.8 to -0.45, p < 0.001) and subtotal body bone mineral density, -0.7 g/cm2 (95% CI -1.2 to -0.2, p < 0.001) following surgery. This was accompanied with higher markers of bone resorption, C-terminal telopeptide of type 1 collagen 0.22 ng/ml (95% CI 0.12-0.32, p < 0.001) and osteocalcin, 10.83 ng/ml (95% CI 6.01-15.67, p < 0.001). There was a significant reduction in calcium levels following BS, -3.78 mg/dl (95% CI -6.1 to -1.5, p < 0.001) but no difference in 25-hydroxyvitamin D, phosphate, bone alkaline phosphatase, procollagen type 1 N propeptide or parathyroid hormone.

Interpretation

BS effectively reduces weight in paediatric patients, but RYGB and SG may have adverse effects on bone health in the medium term. It is crucial to monitor and support bone health through appropriate nutritional supplementation and judicious follow-up. Long-term data is needed to fully understand the clinical implications of these findings on bone outcomes.

Funding

Medical Research Council (MRC), United Kingdom.

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

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

Vitamin D status and supplementation before and after Bariatric Surgery: Recommendations based on a systematic review and meta-analysis

Bariatric surgery is associated with a postoperative reduction of 25(OH) vitamin D levels (25(OH)D) and with skeletal complications. Currently, guidelines for 25(OH)D assessment and vitamin D supplementation in bariatric patients, pre- and post-surgery, are still lacking. The aim of this work is to analyse systematically the published experience on 25(OH)D status and vitamin D supplementation, pre- and post-surgery, and to propose, on this basis, recommendations for management. Preoperatively, 18 studies including 2,869 patients were evaluated. Prevalence of vitamin D insufficiency as defined by 25(OH)D < 30 ng/mL (75 nmol/L) was 85%, whereas when defined by 25(OH)D < 20 ng/mL (50 nmol/L) was 57%. The median preoperative 25(OH)D level was 19.75 ng/mL. After surgery, 39 studies including 5,296 patients were analysed and among those undergoing either malabsorptive or restrictive procedures, a lower rate of vitamin D insufficiency and higher 25(OH)D levels postoperatively were observed in patients treated with high-dose oral vitamin D supplementation, defined as ≥ 2,000 IU/daily (mostly D3-formulation), compared with low-doses (< 2,000 IU/daily). Our recommendations based on this systematic review and meta-analysis should help clinical practice in the assessment and management of vitamin D status before and after bariatric surgery. Assessment of vitamin D should be performed pre- and postoperatively in all patients undergoing bariatric surgery. Regardless of the type of procedure, high-dose supplementation is recommended in patients after bariatric surgery.

Nutritional Deficiencies 3 Years After Sleeve Gastrectomy Can Be Limited by a Specialized Multivitamin Supplement

Purpose

Lifelong daily multivitamin supplementation is highly recommended after sleeve gastrectomy (SG). Based on previous research, a specialized multivitamin supplement (MVS) for SG patients was developed and optimized (WLS Optimum 1.0 and 2.0). This study presents its mid-term effectives and compares micronutrient status of SG patients using this specialized MVS to users of standard MVS (sMVS) and non-users of multivitamin supplementation during the first three years post-surgery.

Materials and Methods

Of the 226 participants that were included at baseline, yearly follow-up blood tests were completed by 193 participants (85%) at 12 months, 176 participants (78%) at 24 months, and 140 participants (62%) at 36 months of follow-up. At each time point, participants were divided into four groups: (1) Optimum 1.0, (2) Optimum 2.0, (3) sMVS, and (4) non-users. Serum concentrations (linear mixed-effects models) and the prevalence of micronutrient deficiencies (chi-square tests) during follow-up were compared between the groups.

Results

Users of specialized MVS (Optimum 1.0 and 2.0) had higher serum concentrations of hemoglobin, folic acid, and vitamin D compared to sMVS users and non-users during follow-up. Serum concentrations of vitamin B12 and (corrected) calcium were also higher in specialized MVS users than in non-users. Overall, fewer deficiencies for folic acid and vitamin D were observed in the Optimum groups.

Conclusion

Although the perfect multivitamin supplement for all SG patients does not exist, WLS Optimum was more effective in sustaining normal serum concentrations than standard, over-the-counter supplementation. Non-users of MVS presented with most micronutrient deficiencies and will evidently develop poor nutritional status on the longer term.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s11695-022-06256-w.

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

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

B1 Vitamin Deficiency After Bariatric Surgery, Prevalence, and Symptoms: a Systematic Review and Meta-analysis

B1 deficiency is a very prevalent complication of bariatric surgery. This study reviews prevalence and symptoms of B1 vitamin deficiency after bariatric surgery. PubMed, Scopus, and Web of Science published were searched up to 10 Feb 2022, with the following keywords: Roux-en-Y gastric bypass, one anastomosis gastric bypass, Omega bypass, Mini bypass, Bariatric surgery OR Bariatric surgery, metabolic surgery, Weight loss surgery, Classic gastric bypass, Loop gastric bypass, Gastric Bypass, thiamine OR thiamin, beriberi, B1. A total of 11 studies examining 1494 patients were included in this meta-analysis. Twenty-seven percent of patients who underwent bariatric surgeries experience vitamin B1 deficiency. Thiamine supplements should be prescribed for the patients for the rest of their lives, and also standard post-surgery follow-ups are necessary in terms of monitoring dietary factors.

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.

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.

Factors Affecting Patient Adherence to Multivitamin Intake After Bariatric Surgery: a Multicentre Survey Study from the Patient's Perspective

Purpose

Lifelong multivitamin supplementation is recommended to prevent nutritional deficiencies. Despite this advice, deficiencies are common which may be due to poor adherence to MVS intake. The aim of this study was to identify which factors affect patient adherence to Multivitamin Supplement (MVS) intake after bariatric surgery.

Materials and Methods

A 42-item questionnaire was sent to 15,424 patients from four Dutch bariatric center. In total, 4975 patients wanted to participate of which 361 patients were excluded. A total of 4614 patients were included, and MVS users (n=4274, 92.6%) were compared to non-users (n=340, 7.4%). Most patients underwent Roux-en-Y gastric bypass (64.3%) or sleeve gastrectomy (32.3%).

Results

Seven hundred and ten patients (15.4%) reported inconsistent MVS use and 340 patients (7.4%) did not use any MVS at all. For inconsistent MVS users, most reported reasons included forgetting daily intake (68.3%), gastro-intestinal side effects (25.6%) and unpleasant taste or smell (22.7%), whereas for non-users gastro-intestinal side effects (58.5%), high costs (13.5%) and the absence of vitamin deficiencies (20.9%) were most frequently reported. Overall, 28.5% were dissatisfied about instructions on MVS use, attention paid to MVS use during medical consultation and the extent to which personal preferences were taken into account.

Conclusion

The attitude of bariatric patients towards MVS use is predominantly negative. It is important to provide accurate information on different options for MVS intake and collect information about patient’s personal preferences when prescribing supplements. Improving adherence to MVS intake is challenging and requires implementation of a shared decision-making process, further optimization of MVS formulas and exploring options for reimbursement.

Graphical abstract

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

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

Adherence to Nutritional Supplementation Determines Postoperative Vitamin D Status, but Not Levels of Bone Resorption Marker, in Sleeve-Gastrectomy Patients

BACKGROUND

Taking advantage of isomeric form of vitamin E in the supplement, adherence to supplement could be evaluated by changes in circulating α- and γ-tocopherol concentrations. Accordingly, effects of supplementation on postoperative nutrition and bone metabolism were studied in terms of adherence.

METHODS

Thirty-eight SG patients were all prescribed a postoperative nutritional supplement containing a low dose of vitamin D (600 IU) and calcium (200 mg). Blood samples were collected prior to (M0) and 6 months after (M6) surgery and concentrations of nutrients and C-terminal telopeptide of type I collage (CTX), a marker of bone resorption, were measured. Adherence and non-adherence were stratified according to change (△, M6-M0) in serum α-tocopherol concentrations (> 0 vs. ≤ 0, respectively).

RESULTS

When M0 and M6 were compared, there were significant increases in serum concentrations of 25(OH)D, α-tocopherol and selenium, whereas there were reductions in parathyroid hormone, ferritin, and γ-tocopherol. At M6, the prevalence of vitamin D insufficiency (25(OH)D < 30 ng/mL) and high CTX were 72 and 26%, respectively. When comparison was made between adherence and non-adherence, only △25(OH)D concentrations, but no other nutrients nor postoperative CTX differed. Multiple linear regression demonstrated that postoperative vitamin D status was independently associated with its preoperative concentrations (β = 0.85, p < 0.001) and adherence (β = 0.52, p < 0.05).

CONCLUSION

SG patients' adherence to supplementation, even with a low dose of vitamin D and calcium, determined vitamin D status but not bone resorption marker concentrations, at least within 6 months after surgery.

Optimizing Multivitamin Supplementation for Sleeve Gastrectomy Patients

Purpose

Micronutrient deficiencies are frequently reported after sleeve gastrectomy (SG), and therefore lifelong daily multivitamin supplementation is highly recommended. Based on literature and the results of a previous randomized controlled trial, a specialized multivitamin supplement for SG patients was further optimized (WLS Optimum 2.0, FitForMe). The present study reports on its short-term effectiveness.

Materials and Methods

An open-label study was performed in which 76 patients were included to receive WLS Optimum 2.0 for 12 months (Opt 2.0 group). This group was compared with a group of 75 patients that had received WLS Optimum 1.0 for 12 months during a previous study (Opt 1.0 group).

Results

Intention-to-treat analysis (Opt 1.0, n = 69; Opt 2.0, n = 75) showed higher serum levels of vitamin B12, vitamin B6, and zinc, and a lower prevalence of deficiencies for vitamin B12 and phosphate in the Opt 2.0 group. MCV and serum folic acid levels were higher in the Opt 1.0 group. Over the 12-month study period, mean increase in serum levels of phosphate, vitamin B6, and zinc was higher in the Opt 2.0 group, and MCV and serum vitamin D levels increased more in the Opt 1.0 group.

Conclusion

The present study showed that the use of a specialized multivitamin supplement for SG patients is effective at preventing deficiencies for most vitamins and minerals, specifically in compliant patients. However, a strict follow-up regime remains necessary to monitor nutritional status and to improve patient compliance.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11695-021-05282-4.

Systematic review and meta-analysis of perioperative behavioral lifestyle and nutritional interventions in bariatric surgery: a call for better research and reporting

Bariatric surgery is considered the most effective treatment for people with morbid obesity, and certain interventions could enhance its long-term results. We searched MEDLINE, Embase, Web of Science, CENTRAL, and trial registers up to January 1, 2020. Randomized controlled trials, where behavioral lifestyle or nutritional interventions were provided perioperatively were included. Primary outcome was weight change. Two reviewers independently performed each stage of the review. Altogether 6652 references were screened. 31 studies were included for qualitative synthesis and 22 studies for quantitative synthesis. Interventions varied greatly, thus limiting possibility of synthesizing all results. Six groups of interventions were discerned, and we used standardized mean differences for synthesis. Low to very-low certainty evidence suggests that physical activity, nonvitamin nutritional interventions, vitamins, psychotherapy, and counseling but not combined interventions might bring some benefit regarding short-term postsurgery follow-ups (up to 12 mo), but the estimates varied and results were not statistically significant, except for 12 months follow-ups regarding counseling. Psychotherapy and counseling, but not vitamins and combined interventions, may provide some benefit at longer follow-ups (over 12 mo), but the certainty of evidence was low to very-low and statistically significant results were observed in comparisons including data from single studies with small sample sizes only. Included studies expressed an outcome "weight change" using 20 different measures. Misreporting of data and huge variety of outcomes do not benefit systematic analyses and may possibly lead to confusion of both researchers and readers. We suggest that authors follow a predefined set of outcomes when reporting the results of their studies. The initiative to produce "core outcome set" for clinical trials in bariatric surgery trials is currently underway.

Patient adherence to multivitamin supplementation after bariatric surgery: a narrative review

Morbid obesity is a growing problem worldwide and has subsequently resulted in a wide application of bariatric surgery to achieve long-term weight loss and improvement of obesity-related co-morbidities. In spite of these clinical benefits, vitamin deficiencies are common after bariatric surgery; therefore, lifelong multivitamin supplementation (MVS) is recommended. However, patient adherence to MVS intake is generally poor. The aim of this narrative review is to analyse which factors influence the adherence of MVS intake after bariatric surgery. To provide an extensive overview, we will discuss the different factors that influence MVS use in patients who underwent bariatric surgery, but also review the literature on MVS in other patient groups.

Design and baseline data in the BAriatic surgery SUbstitution and Nutrition study (BASUN): a 10-year prospective cohort study

BACKGROUND

There is still a lack of knowledge on long-term effects of surgical and non-surgical weight-lowering treatments. BASUN is a prospective study with 10 years of follow-up that will observe the effects and consequences of surgical and medical treatment of obesity. The aims are to cover areas where data on long-term outcomes are lacking, e.g., nutritional deficiencies, substance abuse, psychiatric health, as well as patient-reported outcomes.

METHODS

BASUN is a cohort study that recruited study persons with obesity (BMI ≥ 35 kg/m2) referred to the Regional Obesity Centre of Region Västra Götaland. The interventions were Roux-en-Y gastric bypass (RYGB) or Sleeve gastrectomy (SG), or 12 months of structured, multi-professional medical treatment (MT), including very low energy diet, followed by diet and pharmaceutical treatment. The study is not randomized, but based on patients preferences and multidisciplinary assessments. The study persons are examined at baseline, 2, 5, and 10 years with blood tests, measurements and questionnaires. The recruitment period lasted from May 2015 to November 2017.

RESULTS

One thousand one hundred twenty-seven patients were included (74% female). Three hundred eighty-two patients were accepted for medical treatment, 589 for surgical treatment (388 RYGB and 201 SG) and 156 patients left the study without treatment, leaving a final study population of 971 patients. There were slight differences between the treatment groups with regards to age and BMI. Pharmaceutical treatments, level of education, smoking and marital status were not significantly different between the groups.

CONCLUSION

This study will follow 971 obese subjects in clinical practice treated with the best surgical or medical methods currently available. It has the potential to evaluate outcomes usually not reported in short-term studies, and to assist in identifying factors that are of importance for the choices of treatment. The main limitations are non-randomization and differences in baseline characteristics. The large number of participants and the length of the prospective follow-up are major strengths of the study. BASUN is designed to identify both early and late benefits and adverse events of treatment of obesity.

TRIAL REGISTRATION

This trial was prospectively registered on March 03, 2015; NCT03152617.