The bariatric surgery observation programme

PROJECT 1

BAROBS: Retrospective 10-year follow-up study of patient undergoing bariatric surgery

Background

BAROBS, the Bariatric Surgery Observation Study, explores the diverse long-term effects of bariatric surgery, including improvement in health as well as new morbidity. Nearly 60% of 930 patients who underwent bariatric surgery in public hospitals in Central Norway 2003-2009 participated in the first BAROBS wave in 2018-2020, resulting in a data used by several researchers and students. Additional 1400 patients are invited to an ongoing second wave.

Objectives

• To study body composition, comorbidities, morbidity related to the surgical procedure and malabsorption, and quality of life 10-15 years after BS.
• To study mechanism causing abdominal pain after BS.
• To investigate potential causes of suboptimal weight loss more than 10 years after bariatric surgery in terms of food intake, physical activity levels, eating behaviour, homeostatic and hedonic appetite.

Disseminations

• Roth K, Støle M, Vadseth I, Samstad EO, Sandvik J, Hoff DAL. Long-term changes in lung function after Roux-en-Y gastric bypass in patients with severe obesity. Clin Obes. 2024:Online ahead of press.
• Bjerkan KK, Sandvik J, Nymo S, Græslie H, Johnsen G, Mårvik R, Hyldmo ÅA, Kulseng BE, Sommerseth S, Høydal KL, Hoff DAL. Vitamin and mineral deficiency 12 years after Roux-en-Y gastric bypass: A cross-sectional multicenter study. Obes Surg. 2023;33:3178-3185.
• Belgau I, Johnsen G, Græslie H, Mårvik R, Nymo S, Bjerkan K, Hyldmo Å, Klöckner C, Hoff D, Sandvik J. Frequency of cholelithiasis in need of surgical or endoscopic treatment a decade or more after Roux-en-Y gastric bypass. Surg Endoscop. 2023;37:1349-1356.
• Nymo S, Lundanes J, Aukan MI, Sandvik J, Johnsen G, Græslie H, et al. Diet and physical activity are associated with suboptimal weight loss and weight regain 10–15 years after Roux-en-Y gastric bypass: A cross-sectional study. Obesity Research and Clinical Practice. 2022;16(2):163-9.
• Sandvik ECS, Aasarød K, Johnsen G, Hoff DAL, Kulseng B, Hyldmo ÅA, Græslie H, Nymo S, Sandvik J, Fossmark R. The effect of Roux-n-Y gastric bypass on non-alcoholic fatty liver disease fibrosis assessed by FIB-4 and NFS scores – An 11.6 year follow-up study. J Clin Med. 2022;11:4910.
• Bjerkan KK, Sandvik J, Nymo S, Græslie H, Johnsen G, Mårvik R, Hyldmo ÅA, Kulseng BE, Høydal KL, Hoff DAL. The long-term impact of postoperative educational programs on weight loss after Roux-en-Y gastric bypass. Obes Surg. 2022;32:3005-3012.
• Sandvik J, Bjerkan KK, Græslie H, Hoff DAL, Johnsen G, Kløckner C, et al. Iron Deficiency and Anemia 10 Years After Roux-en-Y Gastric Bypass for Severe Obesity. Frontiers in Endocrinology. 2021;12:679066:1-9.
• Strømmen M, Kløckner C, Bjerkan KK, Græslie H, Hoff DAL, Johnsen G, et al. Characteristics of Patients Reporting Presumed Problematic Drinking Behavior After Gastric Bypass: Exploring Long-Term Data From the BAROBS Study. Frontiers in Endocrinology. 2021;12:679006:1-9.
• Sandvik J, Hole T, Kløckner C, Kulseng BE, Wibe A. The Impact of Post-bariatric Abdominoplasty on Secondary Weight Regain After Roux-en-Y Gastric Bypass. Frontiers in Endocrinology. 2020;11:459:1-8.
• Sandvik J, Hole T, Kløckner C, Kulseng BE, Wibe A. Intravenous Iron Treatment in the Prevention of Iron Deficiency and Anaemia After Roux-en-Y Gastric Bypass. Obes Surg. 2020;30(5):1745-52.

Outcomes (finalized and ongoing)

4 PhD thesis, 1 post-doc, 15 master theses, 20 scientific papers. Contributions to revision of Nordic guidelines.

PROJECT 2

BAR-MEDS: Prospective studies on pharmacokinetics of drugs before and after bariatric surgery

Background

Gastrointestinal surgery potentialle affects gastric pH, gastric passage time, intestinal mucosa surface area and subsequent CYP-enzyme activity, as well as the volume of distribution. In BAR-MEDS, we are investigating whether the gastric bypass and gastric sleeve procedures affect drug absorption in both short- and long-term after surgery, measuring 24-hour series of drug concentrations in the blood after administrating the drug. The study is limited to drugs the patients use at the time of surgery.

Objectives

• To study the pharmacokinetics of relevant drugs pre- and post-surgically for patients with obesity.

Impact

Insight into the pharmacokinetics of drugs commonly used by patients with obesity, may point to medications that need to be monitored more closely in the postoperative period.

Period

2016-2026

Contact

Magnus Strømmen

Dissemination

• Schoretsanitis G, Strømmen M, Krabseth M, Helland A, Spigset O. Effects of Sleeve Gastrectomy and Roux-en-Y Gastric Bypass on Escitalopram Pharmacokinetics: A Cohort Study. Ther Drug Monit, 2023 (45): 805-812.
• Rognstad S, Søraas C, Bergland OU, Høieggen A, Strømmen M, Helland A, Opdahl MS. Establishing serum reference ranges for antihypertensive drugs. Ther Drug Monit, 2021(43):116-125.
• Krabseth H, Strømmen M, Spigset O, Helland A. Effect of sleeve gastrectomy on buprenorphine pharmacokinetics: a planned case observation. Clin Ther, 2020 (42):2232-2237.
• Strømmen M, Helland A, Kulseng BE, Spigset O. Increased bioavailability of methadone following sleeve gastrectomy - a planned case observation. Clin Ther. 2016;38(6):1532-6.

PROJECT 3

BAR-TRIAL: Alcohol addiction after gastric bypass and sleeve gastrectomy

Background

It is known that there is an increased risk of alcohol use disorders (AUD) after gastric bypass surgery driven in part by the increased bioavailability of ethanol following the surgery. BAR-TRIAL contains three different work packages investigating different aspects of AUD after gastric bypass (RYGB) and sleeve gastrectomy (SG).

Objectives

WP1 - Mechanism: The pharmacological part of the project compares key pharmacokinetic ethanol variables such as AUC, Cmax and Tmax after RYGB and SG. This study borrows methodology from pharmacology, utilizing a bioequivalence design to assess whether RYGB and SG can be said to be bioequivalent for ethanol.

WP2 - Epidemiology: Using data from the Norwegian Patient Registry for all patients undergoing RYGB and SG at Norwegian public hospitals in the period 2008-2018, this study compares the differences in the procedures’ incidences for AUD.

WP3 – Patients’ experiences: This qualitative study is comprised by in-depth interviews of 35 patients who developed AUD after their bariatric surgery. The study explores their experiences of loosing control of their alcohol intake, providing a complementary perspective to WP1/WP2 as well as generates hypotheses for new studies.

Impact

The project puts the prevention and screening for AUD on the agenda and has led to several changes in our clinic’s procedures, like more extensive alcohol history taking and the use of the PEth biomarker routinely. Parallell, all our patients now undergo a one-hour mandatory patient education solely on this topic. As a result, we have established closer ties with clinics that specialize in substance abuse treatment in order to achieve a more seamless collaboration on the patients with whom we identify substance abuse problems. In a longer perspective, this study can provide a basis for recommending patients one type of bariatric surgery over the other based on an assessment of their individual predisposition to substance abuse problems, contributing to more personalised treatment.

Contact

Magnus Strømmen

Dissemination

• Strømmen M, Bakken IJL, Kløckner C, Sandvik J, Kulseng BE, Holen A. Diagnoses related to abuse of alcohol and addictive substances after gastric bypass and sleeve gastrectomy: a nation-wide registry study from Norway. Surgery for Obesity and Related Diseases. 2019;16(4):464-70.

Outcomes

3 master theses. Pre-operative patient education.

PROJECT 4

BAR-ORAL

Background

In the clinic, we have observed increased oral pathology in the years following bariatric surgery, and in this project we want to investigate whether this is a systemic effect of the operations. These are patients who may already have poor oral health before surgery. More frequent meals after surgery and unfavourable choices of beverages (which must be consumed between meals due to limited stomach volume), in themselves predispose to increased caries and enamel erosion. There may also be physiological effects of bariatric surgery, such as dehydration and hyposalivation, changes in the oral microbiome, and increased inflammation in the gums postoperatively.

Objective

WP1 – Patients’ experiences: Describe the experiences with impaired oral health after surgery, and more specifically what are the barriers and facilitators for seeking dental treatment. This is done with a qualitative design based on a selected sample of patients.

WP2 – Effect of preventive measures: To develop and investigate the effect of different patient education interventions for the prevention of oral complications of bariatric surgery. The three different interventions are 1) an informative website, 2) traditional group-based education, and 3) distribution of samples relevant to caries, erosion, hyposalivation and periodontitis. The study's outcome measures are a knowledge test, self-reported oral hygiene routines and use of water as a thirst-quenching drink.

WP3 – Longitudinal cohort study: Establish a research database based on a 10-year cohort study of patients undergoing bariatric surgery with comparison to patients undergoing medical obesity treatment as well as registry data. Data will consist of clinical oral parameters (caries, erosion, periodontitis, saliva), a biobank consisting of blood and saliva, and self-reported data on oral health.

Impact

The Norwegian specialist health service rarely recognises oral complications of other diseases and treatments. As we do not have universal dental health services in Norway, there is a risk that such problems will develop in the health service's blind spot. This is particularly relevant as we know that the social determinants of poor oral health are the same as for obesity, and that bariatric surgery can potentially accelerate oral pathology.

Increased awareness of this has led to extensive patient education aimed at empowering patients to prevent adverse oral outcomes. It has also led to more collaboration with clinics with expertise in dental anxiety so that patients who are particularly at risk can receive increased follow-up parallel to their bariatric surgery. In the long run, this project may lead to changes in the health authorities' rules for reimbursement treatment.

Contact

Magnus Strømmen

Dissemination

• Line IL, Strømmen M. Tannbehandling etter fedmeoperasjon hos pasient med odontofobi – en kasuistikk. Nor Tannlegeforen Tid. 2024;134:38-43.

Outcome

Comprehensive patient education and educational website www.bar-oral.no. Recently got funding for 1 PhD-student (dentist). One master student is working on initial data.