Weight loss

Unrealistic weight loss expectations in candidates for bariatric surgery (2008): Patients may have unrealistic expectations for how much weight they will lose after surgery.  In this study, patients reported that they would be disappointed with what providers consider “successful” outcomes.  https://pubmed.ncbi.nlm.nih.gov/18201668/

Metabolic Effects of Gastric Bypass Surgery: Is It All About Calories? (2020): Weight loss in Rue-en-Y Gastric Bypass is mainly caused by caloric restriction rather than a change in metabolic or hormonal profile. https://diabetesjournals.org/diabetes/article/69/9/2027/39410/Metabolic-Effects-of-Gastric-Bypass-Surgery-Is-It

Weight regain

Long-term weight regain after gastric bypass: a 5-year prospective study (2008): About half of patients experience weight regain during the first two years after surgery. https://pubmed.ncbi.nlm.nih.gov/18392907/

Weight Regain 10 Years After Roux-en-Y Gastric Bypass (2017): Weight regain continues when patients are followed at 24, 48, 72, 96, and 120 months after surgery.  Younger patients are more susceptible to weight regain.  Factors such as preop BMI, gender, age, and nutritional monitoring do not account for weight regain.  https://pubmed.ncbi.nlm.nih.gov/27798793/

Bone health

Bone Loss in Adolescents After Bariatric Surgery (2011): Adolescents lose significant bone density in the two years following bariatric surgery.  Further research needs to be conducted to determine the impact after two years.  https://publications.aap.org/pediatrics/article-abstract/127/4/e956/65170/Bone-Loss-in-Adolescents-After-Bariatric-Surgery?redirectedFrom=fulltext?autologincheck=redirected

Nutritional deficiency/Malnutrition

Bariatric Surgery and Long-Term Nutritional Issues (2017): Patients who present for weight loss surgery often have pre-existing nutritional deficiencies, and patients should be assessed after weight loss surgery at regular intervals throughout the remainder of their life due to high prevalence of post-operative nutritional deficiencies.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5700383/

The gastric sleeve: losing weight as fast as micronutrients? (2011): Patients should take iron, vitamin B12, vitamin D, and calcium supplements after the gastric sleeve procedure due to serious risk of nutritional deficiency after the gastric sleeve.  https://pubmed.ncbi.nlm.nih.gov/21088925/

Fatal Malnutrition 6 Years after Gastric Bypass Surgery (2010): Potentially fatal protein calorie malnutrition can occur after gastric bypass. Health care providers should ensure that patients undergo thorough, scheduled surveillance for nutritional deficiencies, which should be aggressively treated early in their course to prevent life-threatening complications. https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/416014#:~:text=Potentially%20fatal%20protein%20calorie%20malnutrition,to%20prevent%20life%2Dthreatening%20complications 

Gastrointestinal symptoms and food intolerance 2 years after laparoscopic Roux-en-Y gastric bypass for morbid obesity (2016): At 2 years after surgery, patients undergoing LRYGB have more gastrointestinal complaints than fat people who didn’t get surgery. Food intolerance is a common side-effect of LRYGB independent of degree of weight loss or the presence of other abdominal symptoms. https://pubmed.ncbi.nlm.nih.gov/27990637/

Is Bariatric Surgery a Trigger Factor for Systemic Autoimmune Diseases? (2016): This paper notes that changes occurring in the immune system after WLS are “incompletely understood”. This paper looked at 4 patients undergoing bariatric surgery, who subsequently developed systemic autoimmune diseases. These patients had no symptoms of autoimmune diseases before surgery, but all 4 developed an autoimmune disease within 11.2 months. Two women fulfilled criteria for systemic lupus erythematosus  and 2 men developed rheumatoid arthritis. This paper opines that a causal relationship is difficult to establish because factors that could trigger these diseases are multiple, including genetic susceptibility, time elapsed until achievement of ideal weight, and vitamin deficiencies, among others. 

Supplements may not prevent long-term nutritional deficiency after bariatric surgery (2019): In this article from Endocrine Today, A study is discussed. The study was published in Bariatric Surgical Practice and Patient Care and the results show that in a cohort of adults who underwent bariatric surgery, 73% had at least one nutritional deficiency 5 years later even though 73% reported taking a dietary supplement. A Dr. Mauro Lombardo is quoted saying “We found that regardless of the extensive use of supplements, nutritional deficiencies are common in patients 5 years after bariatric surgery,” https://www.healio.com/news/endocrinology/20190913/supplements-may-not-prevent-longterm-nutritional-deficiency-after-bariatric-surgery?fbclid=IwAR2VWU4ae111biKTiYtdKZzFseYtdttpySQqk3BlwOw-qtXieT5DoOcHdrM

Drug absorption

The effects of gastric bypass surgery on drug absorption and pharmacokinetics (2012): There is a potential for reduced drug absorption after weight loss surgery but it is difficult to draw general conclusions because drugs may or may not be impacted by changes such as stomach acidity and reduced surface area. https://pubmed.ncbi.nlm.nih.gov/22998066/

Alcohol pharmacokinetics

The rewarding effects of alcohol after bariatric surgery: do they change and are they associated with pharmacokinetic changes? (2021): Weight loss surgery patients become more intoxicated more quickly when given the same amount of alcohol as non-surgery patients and find the effects of alcohol more rewarding, which may explain why surgery patients have higher rates of alcohol use disorders than the general public. https://pubmed.ncbi.nlm.nih.gov/34583891/

Effect of Roux-en-Y Gastric Bypass Surgery Converting 2 Alcoholic Drinks to 4 (2015): This research letter to JAMA Surgery described the results of a study done with the same people before and after they had R en Y gastric bypass (RYGB). The results showed that the RYGB increased the rate of delivery of ingested alcohol into their blood circulation which resulted in earlier and higher BAC peaks and a greater feeling of drunkenness. Also, the change caused by the surgery in the alcohol pharmacokinetics showed that consuming approximately 2 drinks in women who have had RYGB surgery looks like what we would see in the BAC of women consuming approximately 4 drinks who have not had surgery. The increased rate of delivery of alcohol to the bloodstream, and the increased amount of alcohol in the bloodstream after RYGB may also help explain why people who have had WLS are at higher risk for developing an AUD. 

Papers that cover multiple issues

Long-term adverse events after sleeve gastrectomy or gastric bypass: a 7-year nationwide, observational, population-based, cohort study (2019): Despite lower 7-year mortality compared to a control group of fat people who did not get WLS, patients undergoing gastric bypass or sleeve gastrectomy had higher risk of hospital admission at least once for late adverse events which included invasive gastrointestinal procedures, other gastrointestinal disorders, nutritional disorders, than did the control patients. They also had higher risks for gastroesophageal reflux disease, gastritis and other upper gastrointestinal symptoms. Small bowel obstruction was the most common adverse event in the sleeve gastrectomy group The risk for long-term adverse events was higher for gastric bypass compared to sleeve gastrectomy. This study also showed that these risks persisted in the long term.  The control groups the surgical patients were compared to were fat people who were admitted to hospitals with ICD-10 codes for obesity, age, sex, BMI, and antidiabetic treatment. There is no information on what kind of medical care they received. 

Mood disorders

Prevalence and Outcomes of Depression After Bariatric Surgery: A Systematic Review and MetaAnalysis (2022): This meta analysis encompassed 33 articles, including a total of 101,223 patients. The prevalence of post-bariatric surgery depression was 15.3% among which severe, moderate, and minimal depression accounted for 1.9%, 5.1% and 64.9% respectively. The abstract of the study states “The prevalence of post-bariatric surgery depression is relatively high reaching up to 64.9%, with almost one in five patients affected by it. Depression is associated with weight regain, eating disorders, and quality of life.”

Health Disparities

Racial Disparities in Bariatric Surgery Complications and Mortality Using the MBSAQIP Data Registry. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7223417/

Weight Stigma

Residual obesity stigma: an experimental investigation of bias against obese and lean targets differing in weight-loss history (2012): This study looked at stigma directed at formerly fat people who lost weight and became thin through dieting or surgery or fat people who lost weight but were still fat. The results suggest that “residual” stigma remains against people who have previously been fat, even when they have lost substantial amounts of weight and regardless of their weight-loss method. Also they propose that seeing the messages in popular media  that our body size is completely within our control may significantly worsen stigma against fat people. 

The Stigma of Obesity Surgery: Negative Evaluations Based on Weight Loss History (2013) 135 participants iinitially viewed an image of a thin person and rated their impression of that individual on a variety of characteristics. Participants were then shown an image of the individual before she/he lost weight and were informed that the weight loss was achieved through surgery or through diet and exercise. Participants once again rated their impressions of that individual. Participants rated the individuals who lost weight through surgery as significantly more lazy and sloppy, less competent and sociable, less attractive, and having less healthy eating habits. The individual who lost weight through diet and exercise, in contrast, was not evaluated as harshly. The participants viewed the surgery patients as less responsible for their weight loss.

Substance abuse

Alcohol use disorders before and after bariatric surgery: a systematic review and meta-analysis (2018): The prevalence of alcohol use disorders increases in patients undergoing gastric bypass surgery but not gastric banding. The risk of developing an AUD did not increase until after the first two years following surgery. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5952017/

Drug- and alcohol- related mortality risk after bariatric surgery: evidence from a 7-year prospective multicenter cohort study (2019): The drug- and alcohol- related mortality rate for bariatric patients is significantly higher than expected, especially after Rue-en-Y procedures.  https://pubmed.ncbi.nlm.nih.gov/31182414/

Follow-up Issues 

The Reality of Long-term Follow-up of Bariatric/Metabolic Surgery Patients—A Conundrum (2017): In this commentary, the authors note “the lack of high-quality long-term data” in bariatric surgery research. They look at The Longitudinal Assessment of Bariatric Surgery (LABS) which is an observational study established by the LABS Consortium to assess the risks and health benefits associated with bariatric surgery. They note that the LABS-2 reported a 90% follow-up of participants at 3 years, but only 69% of follow-up was in person, and data at 7 years were available for only 1300 of the eligible 2277 patients which means there was 7 year data for only 57% of the participants, which limits what we can know about long-term results even when using statistical tools to account for those lost to follow-up.  https://jamanetwork.com/journals/jamasurgery/article-abstract/2664657

Eating disorders

Characterization of Eating Disorders After Bariatric Surgery: A Case Series Study. (2013): The authors look at 12 individuals who were hospitalized on an Eating Disorders unit after developing an ED after getting WLS. The authors believe cases of EDs developing after WLS are under-reported because the symptoms are often subclinical - meaning that the symptoms do not quite meet diagnostic criteria. Looking at the 12 patients, the authors found that six patients would meet criteria for an anorexia nervosa (AN) diagnosis, an additional four met criteria for atypical AN, since they were at a normal weight, and two patients met criteria for bulimia nervosa. What was different about the post WLS patients from typical ED patients were their ages (they were older than usual) and the age on onset for the development of the ED. https://www.researchgate.net/publication/233798489_Eating_disorders_after_bariatric_surgery_A_case_series#:~:text=In%20a%20review%20of%2015%20research%20studies%2C%2014,outcomes%20and%2For%20more%20weight%20gain%20after%20the%20surgery.

Suicidality

Risk of suicide and non-fatal self-harm after bariatric surgery: results from two matched cohort studies (2018): Bariatric surgery was associated with suicide and non-fatal self-harm compared to fat people who did not get surgery. The findings indicate a need for thorough preoperative psychiatric history assessment along with provision of information about increased risk of self-harm following surgery. The increased risks of suicide and self-harm were not related to how much weigh the bariatric surgery patients lost. https://pubmed.ncbi.nlm.nih.gov/29329975/

“But Everything Is Supposed to Get Better After Bariatric Surgery!” Understanding Postoperative Suicide and Self-injury (2019): In this article written for Bariatric Times, the authors review the available literature on suicide and self-harm after surgery and explore possible explanations for this increased risk. It also has some recommendations to the bariatric team on how to minimize risks to patients. ** note: one of the article authors is Lisa DuBreui, co-owner of this website. https://bariatrictimes.com/understanding-postoperative-suicide-self-injury/

Narrative Research

Narrative research can be defined as collecting and analyzing the accounts people tell to describe experiences and offer interpretation. More simply said, these papers use people’s own words to describe their experiences and pull together common themes. 

Untold stories of living with a bariatric body: long-term experiences of weight-loss surgery (2020): This article explores patients’ long-term experiences after undergoing bariatricsurgery. The study argues that undergoing bariatric surgery is a disruptive event with uncertain long-term outcomes and living with a bariatric body as a “vulnerable life”. The study found that people often blame themselves when there are negative outcomes, and that gets in the way of getting assistance and support. https://pubmed.ncbi.nlm.nih.gov/31515826/

“My quality of life is worse compared to my earlier life” Living with chronic problems after weight loss surgery (2010): From the abstract: This article discusses information from interviews with 5 Norwegian women who underwent a RnY Gastric Bypass. These women reported living “normal” lives before surgery, with no illnesses but they were worried about getting illnesses because they were fat and were impacted negatively by the stigma fat people are subjected to and this led them to undergo WLS. After the surgery they reported “profound” changes and that their lives were “dramatically restricted”. Issues included chronic pain, loss of energy, as well as feelings of shame and failure. Their levels of physical activity and social lives were negatively impacted, as were their abilities to parent and be successful at work. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2989899/