Utility of phosphatidylethanol testing as an objective measure of alcohol use during the preoperative evaluation for bariatric surgery.

BACKGROUND: The risk of alcohol use disorder increases after bariatric surgery. Preoperative alcohol use is a risk factor, and this is evaluated during the routine preoperative psychosocial evaluation. However, it is not clear whether patients accurately report their alcohol use. OBJECTIVE: To determine whether an objective measure of alcohol use, phosphatidylethanol (PEth) testing, offers utility beyond self-reported alcohol use during the preoperative evaluation for bariatric surgery. SETTING: Single healthcare system. METHODS: PEth testing was included as part of the routine laboratory work for 139 patients undergoing evaluation for bariatric surgery. PEth testing results were compared with self-reported alcohol use and scores on the Alcohol Use Disorders Identification Test-Concise (AUDIT-C) questionnaire obtained during the preoperative psychosocial evaluation. PEth testing results were categorized into abstinent, light use, moderate use, or heavy use. There were 85 patients who completed both PEth testing and a preoperative psychosocial evaluation. RESULTS: There were 25 participants (29.4%) who had a positive PEth test; about half had moderate or heavy use values (15.3% of the total sample). The majority of participants with a positive PEth test (82.6%) denied recent alcohol use. Of those with PEth values indicating moderate or heavy use, 61.5% did not have an elevated AUDIT-C score. CONCLUSIONS: Patients appeared to underreport their alcohol use during the preoperative psychosocial evaluation. There appears to be utility for routine PEth testing as part of the evaluation process to identify those with risky drinking patterns. Patients with preoperative risky drinking could be educated about their risk and/or referred to programs to mitigate the development of preoperative alcohol misuse.

Association of obesity with illness severity in hospitalized patients with COVID-19: A retrospective cohort study.

BACKGROUND: Although recent studies have shown an association between obesity and adverse coronavirus disease 2019 (COVID-19) patient outcomes, there is a paucity in large studies focusing on hospitalized patients. We aimed to analyze outcomes associated with obesity in a large cohort of hospitalized COVID-19 patients. METHODS: We performed a retrospective study at a tertiary care health system of adult patients with COVID-19 who were admitted between March 1 and April 30, 2020. Patients were stratified by body mass index (BMI) into obese (BMI ≥ 30 kg/m 2) and non-obese (BMI < 30 kg/m 2) cohorts. Primary outcomes were mortality, intensive care unit (ICU) admission, intubation, and 30-day readmission. RESULTS: A total of 1983 patients were included of whom 1031 (51.9%) had obesity and 952 (48.9%) did not have obesity. Patients with obesity were younger (P < 0.001), more likely to be female (P < 0.001) and African American (P < 0.001) compared to patients without obesity. Multivariable logistic models adjusting for differences in age, sex, race, medical comorbidities, and treatment modalities revealed no difference in 60-day mortality and 30-day readmission between obese and non-obese groups. In these models, patients with obesity had increased odds of ICU admission (adjusted OR, 1.37; 95% CI, 1.07-1.76; P = 0.012) and intubation (adjusted OR, 1.37; 95% CI, 1.04-1.80; P = 0.026). CONCLUSIONS: Obesity in patients with COVID-19 is independently associated with increased risk for ICU admission and intubation. Recognizing that obesity impacts morbidity in this manner is crucial for appropriate management of COVID-19 patients.

Predictors of postoperative emergency department visits after laparoscopic bariatric surgery.

BACKGROUND: Postoperative emergency department (ED) visits are a quality metric for bariatric surgical programs. Predictive factors of ED visits that do not result in readmission are not clear. OBJECTIVES: We aimed to identify predictors of ED visits in patients without readmission after laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB). SETTING: The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database. METHODS: The MBSAQIP database was queried for patients who underwent LSG and LRYGB from 2015 through 2017. Patients were grouped by those who presented to the ED (ED group) and those who did not. ED visits analyzed included only those that did not result in readmission. Multivariable forward selection logistic regression was used to report adjusted odds ratios (AORs) with 95% CIs for ED visits. RESULTS: Of 276,073 patients, 257,985 (93.4%) were in the group who did not present to the ED, and 18,088 (6.6%) were in the ED group. Most underwent LSG (71.9%) versus LRYGB (28.1%). Multivariable forward logistic regression identified outpatient treatment for dehydration (AOR, 22.26; 95% CI, 21.30-23.27; P < .001) as the most predictive factor of an ED visit, followed by urinary tract infection (AOR, 7.25; 95% CI, 6.22-8.46; P < .001), wound disruption (AOR, 4.63; 95% CI, 3.09-6.96; P < .001), and surgical site infection (AOR, 3.80; 95% CI, 3.38-4.28; P < .001). CONCLUSIONS: Postoperative complications were the strongest predictors of ED visits after laparoscopic bariatric surgery. Quality improvement initiatives should target these variables to decrease postoperative ED visits.

Perioperative Outcomes of Robotic Versus Laparoscopic Sleeve Gastrectomy in the Super-obese.

BACKGROUND: The robotic platform is often used for bariatric surgery in superobese patients (body mass index ≥ 50 kg/m2) with the assumption that it offers a technical advantage. This study aimed to compare perioperative outcomes of robotic-assisted sleeve gastrectomy (RSG) and laparoscopic sleeve gastrectomy (LSG) in superobese patients. METHODS: The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database was queried for superobese patients undergoing nonrevisional RSG and LSG from 2015 through 2017. Univariate analysis and multivariable logistic regression were used to compare outcomes in RSG and LSG. RESULTS: A total of 61,493 patients (4685 RSG and 56,808 LSG) were identified. Patients were similar in terms of age (RSG 42.3 ± 11.8 versus LSG 42.4 ± 11.7 y; P = 0.60) and body mass index (RSG 56.8 ± 6.9 versus LSG 56.9 ± 7.1 kg/m2; P = 0.17). The RSG group had a longer operative time (102.4 ± 46.0 versus 74.7 ± 37.5 min; P < 0.01) and length of stay (1.79 ± 1.78 versus 1.66 ± 1.51 d; P < 0.01). Overall morbidity (RSG 3.5% versus LSG 3.7%; P = 0.54) and mortality (RSG 0.1% versus LSG 0.1%; P = 0.73) were similar between the two groups. After adjustment, RSG represented an independent risk factor for organ-space surgical site infection (adjusted odds ratio 2.70; 95% confidence interval 1.54-4.73; P < 0.01). CONCLUSIONS: Use of RSG in superobese patients infers higher risk for organ-space surgical site infection and is associated with prolonged operative time and length of stay. This questions the role of robotics in superobese patients undergoing sleeve gastrectomy.

Perioperative Outcomes of Roux-en-Y Gastric Bypass and Sleeve Gastrectomy in Patients with Diabetes Mellitus: an Analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) Database.

BACKGROUND: The safety and efficacy of laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) to treat obesity and associated comorbidities, including diabetes mellitus, is well established. As diabetes may add risk to the perioperative period, we sought to characterize perioperative outcomes of these surgical procedures in diabetic patients. METHODS: Using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database, we identified patients who underwent LSG and LRYGB between 2015 and 2017, grouping by non-diabetics (NDM), non-insulin-dependent diabetics (NIDDM), and insulin-dependent diabetics (IDDM). Primary outcomes included serious adverse events, 30-day readmission, 30-day reoperation, and 30-day mortality. Univariate and multivariable analyses were used to evaluate the outcome in each diabetic cohort. RESULTS: Multivariable analysis of patients who underwent LSG (with NDM patients as reference) showed higher 30-day mortality (NIDDM AOR = 1.52, p = 0.043; IDDM AOR = 1.91, p = 0.007) and risk of serious adverse events (NIDDM AOR = 1.15, p < 0.001; IDDM AOR = 1.58, p < 0.001) in the diabetic versus NDM groups. Multivariable analysis of patients who underwent LRYGB (with NDM patients as reference) showed higher risk of serious adverse events (NIDDM AOR = 1.09, p = 0.014; IDDM AOR = 1.43, p < 0.001) in the diabetic versus NDM groups. CONCLUSIONS: Diabetics who underwent LSG and LRYGB had higher rates of several perioperative complications compared with non-diabetics. IDDM had a stronger association with several perioperative complications compared with NIDDM. This increase in morbidity and mortality is modest and should be weighed against the real benefits of bariatric surgery in patient with obesity and diabetes mellitus.

Dehydration risk factors and impact after bariatric surgery: an analysis using a national database.

BACKGROUND: Dehydration is a common complication after bariatric surgery and often quoted as the reason for emergency department (ED) visits and readmission. OBJECTIVE: We sought to investigate risk factors for dehydration after bariatric surgery and evaluate its impact on ED visits and readmission. SETTING: The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database. METHODS: We used the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database to identify patients who underwent laparoscopic sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass (LRYGB) from 2016 through 2017. The primary outcome was need for outpatient treatment of dehydration within 30 days postsurgery. Secondary outcomes were association between need for outpatient dehydration therapy and 30-day readmission or ED evaluation not resulting in admission. RESULTS: Of 256,817 patients, 73% underwent laparoscopic sleeve gastrectomy and 27% LRYGB. Of 9592 patients who required dehydration treatment, they were more often younger than age 40, female, black, had a ≥3-day length of stay during their index admission, and experienced a postoperative complication. More patients receiving LRYGB than laparoscopic sleeve gastrectomy required treatment for dehydration. On multivariable analysis, independent-risk factors for postoperative dehydration treatment included LRYGB, length of stay ≥3 days, gastroesophageal reflux disease, hypertension, previous deep vein thrombosis, chronic steroid/immunosuppression, and a postoperative complication. Patients who developed dehydration requiring treatment compared with those that did not had adjusted odds ratio of 3.7 (95% confidence interval: 3.44-3.96; P < .001) and 22 (95% confidence interval: 21.05-23.06; P < .001) of readmission and ED visit. CONCLUSION: Dehydration is a strong risk factor for postoperative ED visits and readmission. Closer surveillance and proactive measures for those at higher risk may prevent the development of postoperative dehydration.

A case report of an adjustable gastric band erosion and migration into the jejunum resulting in biliary obstruction.

INTRODUCTION: Laparoscopic adjustable gastric band is a bariatric operation which has lost popularity due to its high rate of reoperation and complications such as band erosion. Erosion may be partial or complete with intragastric migration of the band. Once in the stomach lumen, the band has the potential to migrate into the small bowel. PRESENTATION OF CASE: A 43-year-old male with history of morbid obesity and laparoscopic adjustable gastric band placement presented with abdominal pain secondary to biliary obstruction. Endoscopic retrograde cholangiopancreatography revealed eroded gastric band tubing into the lumen of the stomach and duodenum with resultant distortion of the ampulla. Upon surgical exploration, the band was found to have migrated into the jejunum and was removed through an enterotomy. The patient did well and was discharged home on postoperative day 8. DISCUSSION: Once completely eroded into the gastric lumen, a gastric band can migrate into the small bowel with the distance traveled being limited by the length of the connecting tube. The stretched tubing can result in distortion of the ampulla leading to biliary obstruction. Band erosion should be managed with band removal which can be completed using endoscopic, laparoscopic, or open approach. CONCLUSION: Band migration should be suspected in patients with a history of gastric band placement presenting with bowel or biliary obstruction. Its management depends on the location of the band as well as the expertise of the surgical team.

Perioperative outcomes of laparoscopic Roux-en-Y gastric bypass and sleeve gastrectomy in super-obese and super-super-obese patients: a national database analysis.

BACKGROUND: Evidence remains contradictory for perioperative outcomes of super-obese (SO) and super-super-obese (SSO) patients undergoing bariatric surgery. OBJECTIVE: To identify national 30-day morbidity and mortality of laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) in SO and SSO patients. SETTING: The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database. METHODS: All LSG and LRYGB patients from 2015 through 2017 in the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database were grouped based on body mass index (BMI) as follows: morbidly obese (MO; BMI 35.0-49.9 kg/m2), SO (BMI 50.0-59.9 kg/m2), and SSO (BMI ≥60.0 kg/m2). Complications and mortality within 30 days were compared between BMI groups using Pearson X2 or Fischer's exact tests. Multivariate logistic regression was used to adjust for demographic characteristics and co-morbidities, and adjusted odds ratio (AOR) was reported for each outcome. RESULTS: Of 356,621 patients, 71.6% had LSG and 28.4% LRYGB. A total of 272,195 patients were in the MO group, 65,565 in the SO group, and 18,861 in the SSO group. Higher BMI was associated with increased overall morbidity and mortality. The overall complication rate was significantly higher for SO (AOR = 1.20, 95% confidence interval [CI] 1.13-1.28 for LSG; AOR = 1.08, 95% CI 1.01-1.15 for LRYGB) and SSO (AOR = 1.44, 95% CI 1.31-1.58 for LSG; AOR = 1.31, 95% CI 1.19-1.45 for LRYGB) compared with the MO group. Mortality was also significantly higher for SO (AOR = 1.65, 95% CI 1.10-2.48 for LSG; AOR = 1.85, 95% CI 1.23-2.80 for LRYGB) and SSO (AOR = 3.30, 95% CI 1.98-5.48 for LSG; AOR = 3.32, 95% CI 1.93-5.73 for LRYGB) compared with the MO group. CONCLUSIONS: SO and SSO patients are at increased risk of 30-day morbidity and mortality compared with MO patients. Despite this elevated perioperative risk, the overall risk of these procedures remains low and acceptable especially as bariatric surgery is the durable treatment option for obesity.

Problematic Eating Behaviors Predict Outcomes After Bariatric Surgery.

BACKGROUND: There are no clear psychosocial predictors of weight loss following bariatric surgery. The purpose of this study was to investigate whether preoperative problematic eating behaviors predict weight loss outcomes following bariatric surgery. METHODS: Clinical records were utilized to examine outcomes of 101 patients who completed a pre-surgical psychosocial evaluation and underwent gastric bypass or sleeve gastrectomy. Information analyzed included binge eating history and scores from the Hospital Anxiety and Depression Scale, Yale Food Addiction Scale, and Emotional Eating Scale. Measures of weight loss 1 year post-surgery were compared to pre-surgical assessments. RESULTS: One-year follow-up data were available for 60 patients. Patients with higher levels of eating in response to anger/frustration (p = .02), anxiety (p = .01), or depression (p = .05) were more likely to miss the 1-year follow-up appointment. Eating in response to anger/frustration and depression were related to poorer weight loss outcomes. There was a trend for binge eating to predict greater %EWL (p = .06). A higher number of food addiction symptoms increased the likelihood that patients would experience less weight loss (p = .01). Psychiatric symptoms were not related to weight loss outcomes. CONCLUSIONS: Patients who endorsed higher levels of pre-surgical emotional eating and food addiction symptoms had poorer weight loss 1 year post-surgery. Providers should consider screening patients for these behaviors during the pre-surgical psychosocial evaluation which would allow opportunities for psychotherapy and potential improvement in weight loss outcomes. Future research should examine which interventions are successful at improving problematic eating behaviors.

Pursuing bariatric surgery in an urban area: Gender and racial disparities and risk for psychiatric symptoms.

BACKGROUND: Bariatric surgery is effective for weight loss; however, only a small percentage of those who qualify choose to pursue it. Additionally, although psychiatric symptoms appear to be common among candidates, the risk factors for symptoms are not known. Therefore, the purpose of this study was to examine the characteristics of those who are pursuing bariatric surgery in an urban area, whether demographic disparities continue to exist, and identify characteristics of those who may be at higher risk for experiencing psychiatric symptoms. METHODS: There were 424 bariatric candidates who completed a required psychological evaluation prior to bariatric surgery. RESULTS AND CONCLUSIONS: Bariatric surgery candidates tended to be middle-aged, Caucasian females, which was unexpected when compared to the rates of obesity among these groups. Therefore, it appears that there are disparities in who chooses to seek out bariatric surgery compared to those who may qualify due to their obesity status. Cultural factors may play a role in why males and African Americans seek out bariatric surgery less frequently. Psychiatric symptoms among candidates are also common, with depression symptoms increasing with age and BMI. Perhaps the compounding effects of medical comorbidities over time are contributing to greater depressive symptoms in the older patients. Findings from this study suggest that we may need to explore ways of encouraging younger patients, males, and ethnic minorities to pursue bariatric surgery to increase weight loss success and decrease medical comorbidities.

Variation in utilization of acid-reducing medication at 1 year following bariatric surgery: results from the Michigan Bariatric Surgery Collaborative.

BACKGROUND: Morbidly obese patients undergoing bariatric surgery have high rates of gastroesophageal reflux and are often treated with acid-reducing medications (ARM) such as proton pump inhibitors or H2-blockers. The objective of this study was to evaluate the effect of bariatric procedures on the utilization of ARM. We analyzed data from the clinical registry of the Michigan Bariatric Surgery Collaborative on 35,477 patients undergoing bariatric surgery between January 2006 and October 2012 who completed both baseline and 1-year follow-up surveys. Procedures included laparoscopic adjustable gastric banding (LAGB, n=2,627), Roux-en-Y gastric bypass (RYGB, n=6,410), sleeve gastrectomy (SG, n=1,567), and biliopancreatic diversion with duodenal switch (BPD/DS, n=162). METHODS: Rates of ARM at 1 year by procedure type were compared using logistic regression analysis. Models were adjusted for patient characteristics, baseline co-morbidities, weight loss, and hiatal hernia repair. RESULTS: Overall ARM use at baseline was 37.7% and declined to 29.6% at 1 year after bariatric surgery. The proportion of patients starting an ARM at 1 year when they were not using one at baseline by procedure was LAGB (13.9%), RYGB (19.2%), SG (21.6%), and BPD/DS (26.7%). The proportion of patients discontinuing an ARM at 1 year when they were using one at baseline by procedure was LAGB (55.6%), RYGB (56.2%), SG (37.3%), and BPD/DS (42.1%). Compared with LAGB on multivariable analysis, the likelihood of ARM use at 1 year was higher for SG (OR 1.70, 95% CI 1.45-1.99) and BDP/DS (OR 1.53, CI .97-2.40) but not different for RYGB (OR 1.02, CI .90-1.16). CONCLUSION: Overall ARM use decreases after bariatric surgery; however, it is not uniform and depends on procedure type. SG is a significant predictor for ARM use at 1 year.

Self-reported remission of obstructive sleep apnea following bariatric surgery: cohort study.

BACKGROUND: Evidence on remission of obstructive sleep apnea (OSA) after bariatric surgery and its relation to weight loss is conflicting. We sought to identify factors associated with successful self-reported OSA remission in a large cohort of bariatric surgery patients. METHODS: We analyzed data from the statewide, prospective clinical registry of the Michigan Bariatric Surgery Collaborative and identified 3,550 patients with OSA who underwent a primary bariatric procedure between June 2006 and October 2011 and had at least 1 year of follow-up data. We used multivariate logistic regression to identify preoperative factors associated with successful self-reported OSA remission, defined as discontinuation of continuous positive airway pressure or bilevel positive airway pressure at 1 year. Our regression model also included procedure type and weight loss at 1 year, divided into equal quintiles, as covariates. RESULTS: The overall 1-year self-reported OSA remission rate was 60%. Significant predictors of remission included age category (per 10 yr) (OR .73, CI .69-.78), body mass index category (per 10 units) (OR .57, CI .54-.62), male gender (OR .58, CI .52-.69), hypertension (OR .83, CI .74-.99), depression (OR .78, CI .69-.88), pulmonary disease (OR .88, CI .78-.98), and baseline Health and Activities Limitations Index score (OR 1.70, CI 1.32-2.23). Relative to gastric banding, the adjusted odds of OSA remission were greater with gastric bypass (OR 2.38, CI 1.89-3.08), sleeve gastrectomy (OR 2.01, CI 1.44-2.55), and duodenal switch (OR 2.57, CI 1.02-7.26). The odds ratio of OSA remission increased stepwise through quintiles of 1-year weight loss. Relative to the lowest quintile, the odds ratios of remission in the 2(nd) through 5(th) quintiles were 1.44 (CI 1.11-1.84), 2.03 (CI 1.48-2.57), 2.47 (1.85-3.40), and 3.53 (CI 2.56-4.85). CONCLUSIONS: Weight loss is an important predictor of self-reported OSA remission after bariatric surgery. However, independent of weight loss, there remain significant differences in the likelihood of remission between gastric banding and other bariatric procedures. This suggests that there may be metabolic, weight-independent effects of procedure type on self-reported OSA remission.

To eat or not to eat; is that really the question? An evaluation of problematic eating behaviors and mental health among bariatric surgery candidates.

Problematic eating behaviors, such as emotional eating, and food addiction, may affect weight; however, little is known about these eating behaviors, especially among those seeking bariatric surgery. Therefore, the purpose of this study was to estimate the prevalence of problematic eating behaviors and to investigate their relationship with other eating behaviors, body mass index (BMI), and psychiatric symptoms. There were 142 patients who completed a required psychiatric evaluation prior to bariatric surgery. Of these, 16.9 % met criteria for a food addiction and 25.4-40.7 % endorsed emotional eating, depending on type of emotional eating. The number of food addiction symptoms endorsed was related to emotional eating. Both food addiction and emotional eating were related to anxiety and depressive symptoms. However, surprisingly, BMI was not related to a food addiction diagnosis, emotional eating scores, or psychiatric symptoms. Results from this study suggest that problematic eating behaviors are occurring among bariatric surgery candidates. Furthermore, this study may help to address the conflicting research regarding the effects of psychiatric symptoms on weight-loss outcomes. Perhaps it is the problematic eating behaviors (e.g., food addiction and emotional eating) that are associated with psychiatric symptoms that could be influencing outcomes. Future research should evaluate treatments for problematic eating behaviors and whether treatments improve weight-loss success.

The comparative effectiveness of sleeve gastrectomy, gastric bypass, and adjustable gastric banding procedures for the treatment of morbid obesity.

OBJECTIVE: To evaluate the comparative effectiveness of sleeve gastrectomy (SG), laparoscopic gastric bypass (RYGB), and laparoscopic adjustable gastric banding (LAGB) procedures. BACKGROUND: Citing limitations of published studies, payers have been reluctant to provide routine coverage for SG for the treatment of morbid obesity. METHODS: Using data from an externally audited, statewide clinical registry, we matched 2949 SG patients with equal numbers of RYGB and LAGB patients on 23 baseline characteristics. Outcomes assessed included complications occurring within 30 days, and weight loss, quality of life, and comorbidity remission at 1, 2, and 3 years after bariatric surgery. RESULTS: Matching resulted in cohorts of SG, RYGB, and LAGB patients that were well balanced on baseline characteristics. Overall complication rates among patients undergoing SG (6.3%) were significantly lower than for RYGB (10.0%, P < 0.0001) but higher than for LAGB (2.4%, P < 0.0001). Serious complication rates were similar for SG (2.4%) and RYGB (2.5%, P = 0.736) but higher than for LAGB (1.0%, P < 0.0001). Excess body weight loss at 1 year was 13% lower for SG (60%) than for RYGB (69%, P < 0.0001), but was 77% higher for SG than for LAGB (34%, P < 0.0001). SG was similarly closer to RYGB than LAGB with regard to remission of obesity-related comorbidities. CONCLUSIONS: With better weight loss than LAGB and lower complication rates than RYGB, SG is a reasonable choice for the treatment of morbid obesity and should be covered by both public and private payers.

Risks and benefits of prophylactic inferior vena cava filters in patients undergoing bariatric surgery.

BACKGROUND: The United States Food and Drug Administration recently issued a warning about adverse events in patients receiving inferior vena cava (IVC) filters. OBJECTIVE: To assess relationships between IVC filter insertion and complications while controlling for differences in baseline patient characteristics and medical venous thromboembolism prophylaxis. DESIGN: Propensity-matched cohort study. SETTING: The prospective, statewide, clinical registry of the Michigan Bariatric Surgery Collaborative. PATIENTS: Bariatric surgery patients (n=35,477) from 32 hospitals during the years 2006 through 2012. INTERVENTION: Prophylactic IVC filter insertion. MEASUREMENTS: Outcomes included the occurrence of complications (pulmonary embolism, deep vein thrombosis, and overall combined rates of complications by severity) within 30 days of bariatric surgery. RESULTS: There were no significant differences in baseline characteristics among the 1,077 patients with IVC filters and in 1,077 matched control patients. Patients receiving IVC filters had higher rates of pulmonary embolism (0.84% vs 0.46%; odds ratio [OR], 2.0; 95% confidence interval [CI], 0.6-6.5; P=0.232), deep vein thrombosis (1.2% vs 0.37%; OR, 3.3; 95% CI, 1.1-10.1; P=0.039), venous thromboembolism (1.9% vs 0.74%; OR, 2.7; 95% CI, 1.1-6.3, P=0.027), serious complications (5.8% vs 3.8%; OR, 1.6; 95% CI, 1.0-2.4; P=0.031), permanently disabling complications (1.2% vs 0.37%; OR, 4.3; 95% CI, 1.2-15.6; P=0.028), and death (0.7% vs 0.09%; OR, 7.0; 95% CI, 0.9-57.3; P=0.068). Of the 7 deaths among patients with IVC filters, 4 were attributable to pulmonary embolism and 2 to IVC thrombosis/occlusion. CONCLUSIONS: We have identified no benefits and significant risks to the use of prophylactic IVC filters among bariatric surgery patients and believe that their use should be discouraged.

Comparative effectiveness of unfractionated and low-molecular-weight heparin for prevention of venous thromboembolism following bariatric surgery.

OBJECTIVE: To evaluate the effectiveness and safety of 3 predominant venous thromboembolism (VTE) prophylaxis strategies among patients undergoing bariatric surgery. DESIGN: Cohort study. SETTING: The Michigan Bariatric Surgery Collaborative, a statewide clinical registry and quality improvement program. PATIENTS: Twenty-four thousand seven hundred seventy-seven patients undergoing bariatric surgery between 2007 and 2012. INTERVENTIONS: Unfractionated heparin preoperatively and postoperatively (UF/UF), UF heparin preoperatively and low-molecular-weight heparin postoperatively (UF/LMW), and LMW heparin preoperatively and postoperatively (LMW/LMW). MAIN OUTCOME MEASURES: Rates of VTE, hemorrhage, and serious hemorrhage (requiring >4 U of blood products or reoperation) occurring within 30 days of surgery. RESULTS: Overall, adjusted rates of VTE were significantly lower for the LMW/LMW (0.25%; P < .001) and UF/LMW (0.29%; P = .03) treatment groups compared with the UF/UF group (0.68%). While UF/LMW (0.22%; P = .006) and LMW/LMW (0.21%; P < .001) were similarly effective in patients at low risk of VTE (predicted risk <1%), LMW/LMW (1.46%; P = .10) seemed more effective than UF/LMW (2.36%; P = .90) for high-risk (predicted risk ≥1%) patients. There were no significant differences in rates of hemorrhage or serious hemorrhage among the treatment strategies. CONCLUSION: Low-molecular-weight heparin is more effective than UF heparin for the prevention of postoperative VTE among patients undergoing bariatric surgery and does not increase rates of bleeding.

Predicting risk for serious complications with bariatric surgery: results from the Michigan Bariatric Surgery Collaborative.

OBJECTIVES: To develop a risk prediction model for serious complications after bariatric surgery. BACKGROUND: Despite evidence for improved safety with bariatric surgery, serious complications remain a concern for patients, providers and payers. There is little population-level data on which risk factors can be used to identify patients at high risk for major morbidity. METHODS: The Michigan Bariatric Surgery Collaborative is a statewide consortium of hospitals and surgeons, which maintains an externally-audited prospective clinical registry. We analyzed data from 25,469 patients undergoing bariatric surgery between June 2006 and December 2010. Significant risk factors on univariable analysis were entered into a multivariable logistic regression model to identify factors associated with serious complications (life threatening and/or associated with lasting disability) within 30 days of surgery. Bootstrap resampling was performed to obtain bias-corrected confidence intervals and c-statistic. RESULTS: Overall, 644 patients (2.5%) experienced a serious complication. Significant risk factors (P < 0.05) included: prior VTE (odds ratio [OR] 1.90, confidence interval [CI] 1.41-2.54); mobility limitations (OR 1.61, CI 1.23-2.13); coronary artery disease (OR 1.53, CI 1.17-2.02); age over 50 (OR 1.38, CI 1.18-1.61); pulmonary disease (OR 1.37, CI 1.15-1.64); male gender (OR 1.26, CI 1.06-1.50); smoking history (OR 1.20, CI 1.02-1.40); and procedure type (reference lap band): duodenal switch (OR 9.68, CI 6.05-15.49); laparoscopic gastric bypass (OR 3.58, CI 2.79-4.64); open gastric bypass (OR 3.51, CI 2.38-5.22); sleeve gastrectomy (OR 2.46, CI 1.73-3.50). The c-statistic was 0.68 (bias-corrected to 0.66) and the model was well-calibrated across deciles of predicted risk. CONCLUSIONS: We have developed and validated a population-based risk scoring system for serious complications after bariatric surgery. We expect that this scoring system will improve the process of informed consent, facilitate the selection of procedures for high-risk patients, and allow for better risk stratification across studies of bariatric surgery.

Preoperative placement of inferior vena cava filters and outcomes after gastric bypass surgery.

OBJECTIVE: To assess relationships between inferior vena cava (IVC) filter placement and complications within 30 days of gastric bypass surgery. SUMMARY OF BACKGROUND DATA: IVC filters are increasingly being used as prophylaxis against postoperative pulmonary embolism in patients undergoing bariatric surgery, despite a lack of evidence of effectiveness. METHODS: On the basis of data from a prospective clinical registry involving 20 Michigan hospitals, we identified 6376 patients undergoing gastric bypass surgery between 2006 and 2008. We then assessed relationships between IVC filter placement and complications within 30 days of surgery. We used propensity scores and fixed effects logistic regression to control for potential selection bias. RESULTS: A total of 542 gastric bypass patients (8.5%) underwent preoperative IVC filter placement, most of whom (65%) had no history of venous thromboembolism. The use of IVC filters for gastric bypass patients varied widely across hospitals (range, 0%-34%). IVC filter patients did not have reduced rates of postoperative venous thromboembolism (adjusted odds ratio [OR], = 1.28; 95% confidence interval [CI], 0.51-3.21), serious complications (adjusted OR, = 1.40; 95% CI, 0.91-2.16), or death/permanent disability (adjusted OR, = 2.49; 95% CI, 0.99-6.26). More than half (57%) of the IVC filter patients in the latter group had a fatal pulmonary embolism or complications directly related to the IVC filter itself, including filter migration or thrombosis of the vena cava. In subgroup analyses, we were unable to identify any patient group for whom IVC filters were associated with improved outcomes. CONCLUSIONS: Prophylactic IVC filters for gastric bypass surgery do not reduce the risk of pulmonary embolism and may lead to additional complications.

Hospital complication rates with bariatric surgery in Michigan.

CONTEXT: Despite the growing popularity of bariatric surgery, there remain concerns about perioperative safety and variation in outcomes across hospitals. OBJECTIVE: To assess complication rates of different bariatric procedures and variability in rates of serious complications across hospitals and according to procedure volume and center of excellence (COE) status. DESIGN, SETTING, AND PATIENTS: Involving 25 hospitals and 62 surgeons statewide, the Michigan Bariatric Surgery Collaborative (MBSC) administers an externally audited, prospective clinical registry. We evaluated short-term morbidity in 15,275 Michigan patients undergoing 1 of 3 common bariatric procedures between 2006 and 2009. We used multilevel regression models to assess variation in risk-adjusted complication rates across hospitals and the effects of procedure volume and COE designation (by the American College of Surgeons or American Society for Metabolic and Bariatric Surgery) status. MAIN OUTCOME MEASURE: Complications occurring within 30 days of surgery. RESULTS: Overall, 7.3% of patients experienced perioperative complications, most of which were wound problems and other minor complications. Serious complications were most common after gastric bypass (3.6%; 95% confidence interval [CI], 3.2%-4.0%), followed by sleeve gastrectomy (2.2%; 95% CI, 1.2%-3.2%), and laparoscopic adjustable gastric band (0.9%; 95% CI, 0.6%-1.1%) procedures (P < .001). Mortality occurred in 0.04% (95% CI, 0.001%-0.13%) of laparoscopic adjustable gastric band, 0 sleeve gastrectomy, and 0.14% (95% CI, 0.08%-0.25%) of the gastric bypass patients. After adjustment for patient characteristics and procedure mix, rates of serious complications varied from 1.6% (95% CI, 1.3-2.0) to 3.5% (95% CI, 2.4-5.0) (risk difference, 1.9; 95% CI, 0.08-3.7) across hospitals. Average annual procedure volume was inversely associated with rates of serious complications at both the hospital level (< 150 cases, 4.1%; 95% CI, 3.0%-5.1%; 150-299 cases, 2.7%; 95% CI, 2.2-3.2; and > or = 300 cases, 2.3%; 95% CI, 2.0%-2.6%; P = .003) and surgeon level (< 100 cases, 3.8%; 95% CI, 3.2%-4.5%; 100-249 cases, 2.4%; 95% CI, 2.1%-2.8%; > or = 250 cases, 1.9%; 95% CI, 1.4%-2.3%; P = .001). Adjusted rates of serious complications were similar in COE and non-COE hospitals (COE, 2.7%; 95% CI, 2.5%-3.1%; non-COE, 2.0%; 95% CI, 1.5%-2.4%; P = .41). CONCLUSIONS: The frequency of serious complications among patients undergoing bariatric surgery in Michigan was relatively low. Rates of serious complications are inversely associated with hospital and surgeon procedure volume, but unrelated to COE accreditation by professional organizations.

Respiratory medication prescriptions before and after bariatric surgery.

BACKGROUND: Increased body mass index is associated with asthma and frequent respiratory complaints. Bariatric surgery often results in rapid weight loss associated with an improved respiratory status. OBJECTIVE: To assess whether patients undergoing bariatric surgery would have fewer respiratory symptoms after surgery as evidenced by decreases in respiratory prescription drug claims. METHODS: A retrospective cohort of 320 patients continuously enrolled in a large, southeast Michigan health maintenance organization were studied for 1 year before and 1 year after bariatric surgery. The health maintenance organization claims database was used to compare respiratory prescriptions filled before and after surgery. Respiratory medications included bronchodilator inhalers, inhaled corticosteroids, oral corticosteroids, theophylline, and leukotriene antagonists. RESULTS: Of 320 surgical patients, 64 (20%) filled at least 1 respiratory medication prescription for a total of 468 prescriptions during the 2-year observation period. Of the prescriptions filled, 35% were beta-agonists, 38% inhaled corticosteroids, 12% oral corticosteroids, 15% leukotriene antagonists, and less than 1% theophylline. Total respiratory medication prescription fills decreased by 49% (from 314 to 154 prescriptions) in the postsurgical year, with only 43.1% of patients filling prescriptions in the year before surgery also filling a prescription in the postsurgical surveillance period. Analyses restricted to 40 patients with physician-diagnosed asthma revealed mean (SD) presurgical prescription fills of 7.0 (6.9) per year, decreasing to 3.8 (6.1) per year in the postsurgical year (P = .002). CONCLUSION: Respiratory medication use decreases significantly after bariatric surgery. A secondary benefit of bariatric surgery may include a decrease in respiratory symptoms and concomitant medication use.