Relative contribution of modifiable versus non-modifiable factors as predictors of racial variance in roux-en-Y gastric bypass weight loss outcomes

Long-term outcomes following laparoscopic Roux-en-Y gastric bypass: weight loss and resolution of comorbidities at 15 years and beyond

BACKGROUND

Laparoscopic Roux-en-Y gastric bypass (LRYGB) is the gold-standard bariatric procedure with proven efficacy in morbidly obese populations. While the short-term benefits of LRYGB have been well-documented, durable weight loss and long-term resolution of obesity-related comorbidities have been less clearly described.

METHODS

This single-center study prospectively reports weight loss and comorbidity resolution in patients undergoing LRYGB between August 2001 and September 2007 with at least 15-year follow-up. Data were collected at the time of surgery; 1, 3, 6, and 12 months postoperatively; and then annually thereafter.

RESULTS

A total of 486 patients were included in this analysis. Patients were predominantly female (88.7%), and the median age was 36.0 [IQR 29.0-45.0] years. Patients were ethnically diverse, including Black/African American (43.6%), White/Caucasian (35.0%), Hispanic (18.3%), and other backgrounds (3.1%). Mean preoperative weight and body mass index were 133.0 ± 21.9 kg and 48.4 ± 6.5 kg/m2, and the median number of comorbidities was 6.0 [IQR 4.0-7.0]. Follow-up rates at 1, 5, 10, and 15 years were 75.3%, 37.2%, 35.2%, and 18.9%, respectively. On average, maximum percentage total weight loss (%TWL) occurred 2 years postoperatively (- 36.2 ± 9.5%), and ≥ 25% TWL was consistently achieved at 1, 5, 10, and 15-year time intervals (- 28.0 ± 13.0% at 15 years). Patients with comorbidities experienced improvement or resolution of their conditions within 1 year, including type 2 diabetes mellitus (83/84, 98.8%), obstructive sleep apnea (112/116, 96.6%), hypertension (142/150, 94.7%), and gastroesophageal reflux disease (217/223, 97.3%). Rates of improved/resolved comorbidities remained consistently high through at least 10 years after surgery.

CONCLUSIONS

LRYGB provides durable weight loss for at least 15 years after surgery, with stable average relative weight loss of approximately 25% from baseline. This outcome corresponds with sustainable resolution of obesity-related comorbidities for at least 10 years after the initial operation.

Predictors of 30-day follow-up visit completion after primary bariatric surgery: an analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data registry

BACKGROUND

Adherence to follow-up visits is often unsatisfactory after bariatric surgery.

OBJECTIVES

To identify predictors, including surgery type and preoperative demographics, body mass index (BMI), medical conditions, and smoking status, of 30-day follow-up visit completion.

SETTING

Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program participating centers (2015-2018).

METHODS

Patients who underwent primary Roux-en-Y gastric bypass or sleeve gastrectomy were included in this analysis. Data were analyzed using weighted logistic regression. Subanalyses included stratification of the sample by sex and age (<45, 45-60, and >60 years).

RESULTS

Patients (n = 566,774) were predominantly female (79.6%), White (72.4%), non-Hispanic (77.9%), and middle-aged (44.5 ± 11.9 years), with a mean BMI of 45.3 ± 7.8 kg/m². More than 95% of patients completed the 30-day visits. In the whole-sample analysis, older age (odds ratio [OR], 1.02) and the presence of non-insulin-dependent diabetes (OR, 1.04), hypertension (OR, 1.03), hyperlipidemia (OR, 1.10), obstructive sleep apnea (OR, 1.15), and gastroesophageal reflux disease (OR, 1.16) were positive predictors of the 30-day visit completion (P_s < .01). Conversely, sleeve gastrectomy procedure (OR, .86), Black race (OR, .87), Hispanic ethnicity (OR, .94), and the presence of insulin-dependent diabetes (OR, .96) and smoking (OR, .83) were negative predictors (P_s < .01). Several differences emerged in subanalyses. For example, in sex stratification, Hispanic ethnicity lost its significance in men. In age stratification, BMI and male sex emerged as positive predictors in the age groups of <45 and 45-60 years, respectively.

CONCLUSION

Although challenged by small effect sizes, this analysis identified subgroups at a higher risk of being lost to follow-up after bariatric surgery.

10-year weight loss outcomes after Roux-en-Y gastric bypass and attendance at follow-up visits: a single-center study

BACKGROUND

Long-term durability of weight loss is a prerequisite for a greater acceptance of bariatric surgery.

OBJECTIVES

To examine long-term weight trajectory in patients undergoing Roux-en-Y gastric bypass (RYGB) and determine factors predicting long-term follow-up and weight outcomes.

SETTING

University hospital.

METHODS

A retrospective cohort of adults who underwent RYGB during 1997-2010 were identified and followed until 2017. Predictors for attendance at periodic follow-up visits, reduction in body mass index (BMI), and percent excess BMI lost were determined using multivariable logistic regression and linear mixed-effects models. The latter was used to predict long-term weight outcomes for a typical patient.

RESULTS

The study included 1104 patients with a mean age of 45.5 (standard deviation [SD] 9.9) years and a preoperative BMI of 54.7 (SD 10.9) kg/m². Follow-up data were available for 92.8% of the patients after 1 year, 50.0% after 5 years, and 35.2% after 10 years post-surgery. Black patients, compared with White patients, were less likely to attend follow-up visits. Attendance at follow-up visits at least every other year was not associated with larger weight loss, but higher preoperative BMI, being White (versus Black), and female sex were. Predicted BMI reduction for a typical patient, a 45-year-old White female with a preoperative BMI of 54.7 kg/m² and private health insurance, undergoing laparoscopic RYGB in 2004, was 18.3 (standard error [SE] .36) kg/m² at year 5 and 17.6 (SE .49) kg/m² at year 10.

CONCLUSION

RYGB results in clinically significant and durable weight loss. Attendance at periodic follow-up visits does not appear to be associated with long-term weight loss outcomes. Future work should focus on strategies to remove barriers to post-operative care.

Racial disparities in bariatric surgery postoperative weight loss and co-morbidity resolution: a systematic review

While bariatric surgery is an accepted treatment for morbid obesity, the impact of race on surgical outcomes remains unclear. This systematic review aims to compare differences in weight loss and co-morbidity outcomes among various races after bariatric surgery. PubMed, Medline, and SCOPUS databases were queried to identify publications that included more than 1 racial group and reported weight loss outcomes after bariatric surgery. A total of 52 studies were included. Non-Hispanic black (NHB) patients comprised between 5.5% and 69.7% and Hispanic patients comprised between 4.7% and 65.3% of the studies' populations. Definitions of weight loss success differed widely across studies, with percent excess weight loss being the most commonly reported outcome, followed by percent total weight loss and change in body mass index (BMI). Statistical analyses also varied, with most studies adjusting for age, sex, preoperative weight, or BMI. Some studies also adjusted for preoperative co-morbidities, including diabetes mellitus, hypertension, and hyperlipidemia, or socioeconomic status, including income, education, and neighborhood poverty. The majority of studies found less favorable weight loss in NHB compared to Hispanic and non-Hispanic white (NHW), patients while generally no difference was found between Hispanic and NHW patients. The trend also indicates no association between race and resolution of obesity-related co-morbidities. Racial minorities lose less weight than NHW patients after bariatric surgery, although the factors associated with this discrepancy are unclear. The heterogeneity in reporting weight loss success and statistical analyses amongst the literature makes an estimation of effect size difficult. Generally, racial disparity was not seen when examining co-morbidity resolution after surgery. More prospective, robust, long-term studies are needed to understand the impacts of race on bariatric surgery outcomes and ensure successful outcomes for all patients, regardless of race.

Characteristics and resolution of hypertension in obese African American bariatric cohort

Weight reduction continues to be first-line therapy in the treatment of hypertension (HTN). However, the long-term effect of bariatric malabsorptive surgical techniques such as Roux-en-Y Gastric Bypass (RYGB) surgery in the management of hypertension (HTN) is less clear. African Americans (AA) are disproportionately affected by obesity and hypertension and have inconsistent outcomes after bariatric surgery (BS). Despite a plethora of bariatric literature, data about characteristics of a predominantly AA bariatric hypertensive cohort including hypertension in obese (HIO) are scarce and underreported. The aims of this study were, (1) to describe the preoperative clinical characteristics of HIO with respect to HTN status and age, and (2) to identify predictors of HTN resolution one year after RYGB surgery in an AA bariatric cohort enrolled at the Howard University Center for Wellness and Weight Loss Surgery (HUCWWS). In the review of 169 AA bariatric patients, the average BMI was 48.50 kg/m2 and the average age was 43.86 years. Obese hypertensive patients were older (46 years vs. 37.89 years; p < .0001); had higher prevalence of diabetes mellitus (DM, 43.09% vs. 10.87%; p < .0001) and dyslipidemia (38.2% vs. 13.04%; p 0.002). Hypertensive AA who were taking ≥ 2 antihypertensive medications prior to RYGB were 18 times less likely to experience HTN resolution compared to hypertensive AA taking 0-1 medications, who showed full or partial response. Also, HIO was less likely to resolve after RYGB surgery in patients who needed ≥ 2 antihypertensive medications prior to surgical intervention.

Characteristics and resolution of hypertension in obese African American bariatric cohort

Weight reduction continues to be first-line therapy in the treatment of hypertension (HTN). However, the long-term effect of bariatric malabsorptive surgical techniques such as Roux-en-Y Gastric Bypass (RYGB) surgery in the management of hypertension (HTN) is less clear. African Americans (AA) are disproportionately affected by obesity and hypertension and have inconsistent outcomes after bariatric surgery (BS). Despite a plethora of bariatric literature, data about characteristics of a predominantly AA bariatric hypertensive cohort including hypertension in obese (HIO) are scarce and underreported. The aims of this study were, (1) to describe the preoperative clinical characteristics of HIO with respect to HTN status and age, and (2) to identify predictors of HTN resolution one year after RYGB surgery in an AA bariatric cohort enrolled at the Howard University Center for Wellness and Weight Loss Surgery (HUCWWS). In the review of 169 AA bariatric patients, the average BMI was 48.50 kg/m2 and the average age was 43.86 years. Obese hypertensive patients were older (46 years vs. 37.89 years; p < .0001); had higher prevalence of diabetes mellitus (DM, 43.09% vs. 10.87%; p < .0001) and dyslipidemia (38.2% vs. 13.04%; p 0.002). Hypertensive AA who were taking ≥ 2 antihypertensive medications prior to RYGB were 18 times less likely to experience HTN resolution compared to hypertensive AA taking 0-1 medications, who showed full or partial response. Also, HIO was less likely to resolve after RYGB surgery in patients who needed ≥ 2 antihypertensive medications prior to surgical intervention.

Handgrip Strength and Phase Angle Predict Outcome After Bariatric Surgery

BACKGROUND

The amount of postoperative weight loss after bariatric surgery varies interindividually. The quality of the pre- and postoperative body composition is an important predictor of success. The aim of this study was to investigate the role of preoperative handgrip strength and phase angle (PhA) as predictors of sustained postoperative weight loss in order to assess the influence of body composition on the postoperative outcome after bariatric surgery.

METHOD

In a prospective cohort study, bioelectrical impedance and follow-up data of 198 patients after laparoscopic sleeve gastrectomy (SG; n = 68) and Roux-en-Y gastric bypass (GB; n = 130) were analyzed for a period of 36 months postoperatively.

RESULTS

The mean preoperative handgrip strength (31.48 kg, SD 9.97) correlates significantly with the postoperative body composition up to 24 months after surgery. Preoperative PhA, gender, size, and body weight influenced postoperative weight loss significantly. A significant correlation between preoperative PhA (mean 6.18°, SD 0.89°) and total weight loss (%TWL) was observed up to 3 months after SG (r = 0.31444, p = 0.0218) and up to 12 months after GB (r = 0.19184, p = 0.0467). The optimum cutoff for the prediction of a response of less than 50% excess weight loss was a preoperative PhA of 6.0°.

CONCLUSIONS

The preoperative handgrip strength confirmed its suitability for use as a predictor of postoperative body composition, whereas the preoperative PhA predicts postoperative weight loss after bariatric surgery. Further research is necessary to identify the role of these parameters for preconditioning.

Association of Race With Bariatric Surgery Outcomes

Importance

The outcomes of bariatric surgery vary considerably across patients, but the association of race with these measures remains unclear.

Objective

To examine the association of race on perioperative and 1-year outcomes of bariatric surgery.

Design, Setting, and Participants

Propensity score matching was used to assemble cohorts of black and white patients from the Michigan Bariatric Surgery Collaborative who underwent a primary bariatric operation (Roux-en-Y gastric bypass, sleeve gastrectomy, or adjustable gastric banding) between June 2006 and January 2017. Cohorts were balanced on baseline characteristics and procedure. Conditional fixed-effects models were used to evaluate the association of race on outcomes within hospitals and surgeons. Data analysis occurred from June 2006 through August 2018.

Main Outcomes and Measures

Thirty-day complications and health care resource utilization measures, as well as 1-year weight loss, comorbidity remission, quality of life, and satisfaction.

Results

In each group, 7105 patients were included. Black patients had a higher rate of any complication (628 [8.8%] vs 481 [6.8%]; adjusted odds ratio, 1.33 [95% CI, 1.17-1.51]; P = .02), but there were no significant differences in the rates of serious complications (178 [2.5%] vs 135 [1.9%]; adjusted odds ratio, 1.32 [95% CI, 1.05-1.66]; P = .29) or mortality (5 [0.10%] vs 7 [0.10%]; adjusted odds ratio, 0.73 [95% CI, 0.23-2.31]; P = .54). Black patients had a greater length of stay (mean [SD], 2.2 [3.0] days vs 1.9 [1.7] days; adjusted odds ratio, 0.30 [95% CI, 0.20-0.40]; P < .001), as well as a higher rate of emergency department visits (541 [11.6%] vs 826 [7.6%]; adjusted odds ratio, 1.60 [95% CI, 1.43-1.79]; P < .001) and readmissions (414 [5.8%] vs 245 [3.5%]; adjusted odds ratio, 1.73 [95% CI, 1.47-2.03]; P < .001). At 1 year, black patients had lower mean total body weight loss and as a percentage of weight (32.0 kg [26%]; vs 38.3 kg [29%]; P < .001) and this held true across procedures. Remission of hypertension was lower for black patients (564 [40.0%] vs 1096 [56.0%]; P < .001), but the rate of sleep apnea remission (467 [62.6%] vs 615 [56.1%]; P = .005) and gastroesophageal reflux disease (309 [78.6%] vs 453 [75.4%]; P = .049) were higher. There were no significant differences in remission of diabetes with insulin dependence, diabetes without insulin dependence,or hyperlipidemia hyperlipidemia. Fewer black patients than white patients reported a good or very good quality of life (1379 [87.2%] vs 2133 [90.4%]; P = .002) and being very satisfied with surgery (1908 [78.4%] vs 2895 [84.2%]; P < .001) at 1 year.

Conclusions and Relevance

Black patients undergoing bariatric surgery in Michigan had significantly higher rates of 30-day complications and resource utilization and experienced lower weight loss at 1 year than a matched cohort of white patients. While sleep apnea and gastroesophageal reflux disease remission were higher and hypertension remission lower in black patients, comorbidity remission was otherwise similar between matched cohorts. Racial and cultural differences among patients should be considered when designing strategies to optimize outcomes with bariatric surgery.

Racial disparities in perioperative outcomes after bariatric surgery

BACKGROUND

NonHispanic black patients bear a disproportionate burden of the obesity epidemic and its related medical co-morbidities. While bariatric surgery is the most effective treatment for morbid obesity, black patients access bariatric surgery at lower rates than nonHispanic white patients.

OBJECTIVES

To examine racial differences before bariatric surgery and in short-term perioperative outcomes and complications, and the extent to which race is independently associated with perioperative morbidity and mortality.

SETTING

Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program national database.

METHODS

Data were extracted from the 2015 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program Participant Use File. Multivariate analysis was used to identify differences in mortality, length of stay, readmission, and reintervention by race in patients undergoing laparoscopic Roux-en-Y gastric bypass or laparoscopic sleeve gastrectomy (SG).

RESULTS

A total of 108,198 patients were included in the analysis. There were significant differences in perioperative disease burden. Black patients had a higher body mass index at the time they underwent surgery (laparoscopic Roux-en-Y gastric bypass: 48.0 versus 45.7 kg/m2; SG: 46.8 versus 44.9 kg/m2; P < .001). Black patients had significantly longer length of stay and higher rates of readmission in both the laparoscopic Roux-en-Y gastric bypass and SG groups. In the SG group, black patients had significantly higher 30-day mortality (.2% versus .1%, odds ratio = 3.613, 95% confidence interval 1.990-6.558, P < .001) and higher rates of reoperation or reintervention.

CONCLUSIONS

We found significant racial disparities in bariatric surgery outcomes, including higher mortality in black patients undergoing SG. The specific causes of these disparities remain unclear and must be the subject of future research.

Pre-operative Bariatric Clinic Attendance Is a Predictor of Post-operative Clinic Attendance and Weight Loss Outcomes

AIM

Our primary aim was to determine whether non-attendance at pre-operative clinics were associated with non-attendance at post-operative clinics and its influence on weight loss. We also sought to examine the relationship between gender, ethnicity and post-operative clinic attendance with respect to weight loss post-bariatric surgery.

METHODS

A retrospective audit was performed for patients undertaking the bariatric surgery program at the Auckland City Hospital between 2013 and 2016.

RESULTS

One hundred and eighty-four patients completed our program, with a mean age of 46.1 years. Mean weight at commencement was 133.3 kg, with a BMI of 47.4. At 2 years follow-up (n = 143), excess weight loss was 70.8% following RYGB and 68.0% following LSG (p = 0.5743). More patients attended all pre-operative than post-operative clinics (67.4% vs 37.5% p = < 0.001). One pre-operative clinic non-attendance was associated with less weight loss at 2 years and it increases the risk of missing at least 50% of post-operative clinics with a risk ratio of 2.73, p = 0.005. Non-attendance of at least 50% of post-operative clinics was also associated with less weight loss at 2 years (33.4 kg vs 44.3 kg, p = 0.040). Although Maori and Pacific Islanders more frequently missed > 50% of post-operative clinics, weight loss was similar between European, Maori and Pacific Islander populations (2-year weight loss 44.2 kg vs 40.74 kg vs 44.1 kg, respectively, p = 0.8192).

CONCLUSION

Pre-operative clinic non-attendance helps predict post-operative clinic non-attendance. Missing any pre-operative clinics and at least 50% of scheduled post-operative clinics is associated with poorer weight loss outcomes.

Weight Loss After Bariatric Surgery: Do Clinical and Behavioral Factors Explain Racial Differences?

BACKGROUND

Prior studies have suggested less weight loss among African American compared to Caucasian patients; however, few studies have been able to simultaneously account for baseline differences in other demographic, clinical, or behavioral factors.

METHODS

We interviewed patients at two weight loss surgery (WLS) centers and conducted chart reviews before and after WLS. We compared weight loss post-WLS by race/ethnicity and examined baseline demographic, clinical (BMI, comorbidities, quality of life), and behavioral (eating behavior, physical activity level, alcohol intake) factors that might explain observed racial differences in weight loss at 1 and 2 years after WLS.

RESULTS

Of 537 participants who underwent either Roux-en-Y Gastric Bypass (54%) or gastric banding (46%), 85% completed 1-year follow-up and 73% completed 2-year follow-up. Patients lost a mean of 33.00% of initial weight at year 1 and 32.43% at year 2 after bypass and 16.07% and 17.56 % respectively after banding. After adjustment for other demographic characteristics and type of surgery, African Americans lost an absolute 5.93 ± 1.49% less weight than Caucasian patients after bypass (p < 0.001) and 4.72 ± 1.96% less weight after banding. Of the other demographic, clinical, behavioral factors considered, having diabetes and perceived difficulty making dietary changes at baseline were associated with less weight loss among gastric bypass patients whereas having a diagnosis of anxiety disorder was associated with less weight loss among gastric banding patients. The association between race and weight loss did not substantially attenuate with additional adjustment for these clinical and behavioral factors, however.

CONCLUSION

African American patients lost significantly less weight than Caucasian patients. Racial differences could not be explained by baseline demographic, clinical, or behavioral characteristics we examined.

Surgical Treatment of Obesity in Latinos and African Americans: Future Directions and Recommendations to Reduce Disparities in Bariatric Surgery

Introduction: Obesity and metabolic syndrome are increasingly prevalent in the United States, particularly among African Americans and Latinos. Bariatric surgery has become one of the primary treatment modalities for obesity and type 2 diabetes. However, fewer Latinos and African Americans are undergoing bariatric surgery than whites. The aim of this article is to describe the disparities in seeking and accessing bariatric surgery, describe the outcomes following bariatric procedures in Latinos and African Americans, and offer recommendations and future research directions that may assist in addressing these disparities. Methods: Original research and review articles published in English were reviewed. Results: Potential reasons why Latinos and African Americans have low rates of seeking bariatric surgery are described. Disparities in access to care and financial coverage, low rates of referral by primary care providers, and cultural attitudes toward obesity in conjunction with mistrust of the healthcare system are discussed as potential contributors to the low rate of bariatric surgery in Latinos and African Americans. Finally, disparities in bariatric surgery outcomes, comorbidities, and complications are reviewed. Conclusions: Additional research studies in bariatric surgical disparities are needed. Recommendations and future directions that may help to reduce disparities in bariatric surgery are discussed.

Long-Term Effect of Gastric Bypass and Sleeve Gastrectomy on Severe Obesity: Do Preoperative Weight Loss and Binge Eating Behavior Predict the Outcome of Bariatric Surgery?

BACKGROUND

Few studies have examined weight loss sustainability after sleeve gastrectomy (SG). The purpose of this study was to determine long-term outcome after SG and gastric bypass (GBP) and learn whether preoperative weight loss and binge eating behavior can be used to predict outcome.

MATERIALS AND METHODS

Together, 257 patients (64 % women) were operated, 163 by GBP and 94 by SG. Binge eating was assessed by binge eating scale (BES) and preoperative weight loss was advised to all, including very low-calorie diet for 5 weeks. Postoperative visits took place at 1 and 2 years, and long-term outcome was at median 5 years (range 2.29-6.85). Multivariate linear regression analysis was used to predict outcome at 2-year and long-term control.

RESULTS

Median age was 48 years, weight 141.1 kg, and BMI 48.2 kg/m(2). Preoperative weight loss was median 4.9 % before GBP and 3.8 % before SG, P = 0.04. Total weight loss at year one was 24.1 % in GBP and 23.7 % in SG (P = 0.40), at year two 24.4 and 23.4 % (P = 0.26), and at long-term control 23.0 and 20.2 % (P = 0.006), respectively. Weight was analyzed in 93, 88, and 89 % of those alive, respectively. BES did not predict weight outcome, but larger preoperative weight loss predicted less postoperative weight loss at 2 years.

CONCLUSION

On long term, weight loss was better maintained after GBP compared with SG. Binge eating behavior was not a significant predictor, but larger preoperative weight loss predicted less postoperative weight loss for the next 2 years.

Health Disparities in Adolescent Bariatric Surgery: Nationwide Outcomes and Utilization

PURPOSE

Bariatric surgery represents an appropriate treatment for adolescent severe obesity, but its utilization remains low in this patient population. We studied the impact of race and sex on preoperative characteristics, outcomes, and utilization of adolescent bariatric surgery.

METHODS

Retrospective analysis (2007-2014) of adolescent bariatric surgery using the Bariatric Outcomes Longitudinal Database, a national database that collects bariatric surgical care data. We assessed the relationships between baseline characteristics and outcomes (weight loss and remission of obesity-related conditions [ORCs]). Using the National Health and Nutrition Examination Survey and U.S. census data, we calculated the ratio of severe obesity and bariatric procedures among races and determined the ratio of ratios to assess for disparities.

RESULTS

About 1,539 adolescents underwent bariatric surgery. Males had higher preoperative body mass index (BMI; 51.8 ± 10.5 vs. 47.1 ± 8.7, p < .001) and higher rates of obstructive sleep apnea and dyslipidemia. Blacks had higher preoperative BMI (52.4 ± 10.6 vs. 47.3 ± 8.3; 48.7 ± 8.8; 48.2 ± 12.1 kg/m2; whites, Hispanics, and others, respectively p < .001) and higher rates of hypertension, obstructive sleep apnea, and asthma. Weight loss and ORCs remission rates did not differ between sexes or races after accounting for the rate of severe obesity in each racial group. White adolescents underwent bariatric surgery at a higher proportion than blacks and Hispanics (2.5 and 2.3 times higher, respectively).

CONCLUSIONS

Preoperative characteristics vary according to race and sex. Race and sex do not impact 12-month weight loss or ORC's remission rates. Minority adolescents undergo bariatric surgery at lower-than-expected rates.

The medicalization of obesity, bariatric surgery, and population health

This article examines how the medicalization of obesity validates the use of bariatric surgery to treat obesity in the United States and how expansions in access to bariatric surgery normalize surgical procedures as disease treatment and prevention tools. Building on this discussion, the article poses two questions for population health regarding health technology: (1) to what extent does bariatric surgery treat obesity in the United States while diverting attention away from the ultimate drivers of the epidemic and (2) to what extent does bariatric surgery improve outcomes for some groups in the US population while simultaneously generating disparities? We conduct a brief, historical analysis of the American Medical Association's decision to reclassify obesity as a disease through internal documents, peer-reviewed expert reports, and major media coverage. We use medicalization theory to show how this decision by the American Medical Association channels increased focus on obesity into the realm of medical intervention, particularly bariatric surgery, and use this evidence to review research trends on bariatric surgery. We propose research questions that investigate the population health dimensions of bariatric surgery in the United States and note key areas of future research. Our objective is to generate a discourse that considers bariatric surgery beyond the medical realm to better understand how technological interventions might work collectively with population-level obesity prevention efforts and how, in turn, population health approaches may improve bariatric surgery outcomes.

African Ancestry Gradient Is Associated with Lower Systemic F2-Isoprostane Levels

Context. Low levels of systemic F₂-isoprostanes (F₂-IsoP) increase the risk of diabetes and weight gain and were found in African Americans. Low F₂-IsoPs could reflect an unfavorable metabolic characteristic, namely, slow mitochondrial metabolism in individuals with African ancestry. Objective. To examine differences in plasma F₂-IsoPs in three groups with a priori different proportion of African ancestry: non-Hispanic Whites (NHWs), US-born African Americans (AAs), and West African immigrants (WAI). Design. Cross-sectional study. Setting. Georgia residents recruited from church communities. Participants. 218 males and females 25–74 years of age, who are self-identified as NHW (n = 83), AA (n = 56), or WAI (n = 79). Main Outcome Measure(s). Plasma F₂-IsoPs quantified by gas chromatography-mass spectrometry. Results. After adjustment for age, gender, obesity, and other comorbidities, WAI had lower levels of plasma F₂-IsoP than AA (beta-coefficient = −9.8, p < 0.001) and AA had lower levels than NHW (beta-coefficient = −30.3, p < 0.001). Similarly, among healthy nonobese participants, F₂-IsoP levels were lowest among WAI, followed by AA, and the highest levels were among NHW. Conclusion. Plasma F₂-IsoPs are inversely associated with African ancestry gradient. Additional studies are required to test whether optimization of systemic F₂-IsoP levels can serve as means to improve race-specific lifestyle and pharmacological intervention targeted to obesity prevention and treatment.

Systemic F2-Isoprostane Levels in Predisposition to Obesity and Type 2 Diabetes: Emphasis on Racial Differences

This review focuses on racial differences in systemic levels of lipid peroxidation markers F₂-isoprostanes as metabolic characteristics predisposing to obesity and type 2 diabetes. Elevated levels F₂-isoprostanes were found in obesity, type 2 diabetes and their comorbidities. It was hypothesized that increased F₂-isoprostane levels reflect the obesity-induced oxidative stress that promotes the development of type 2 diabetes. However, African Americans have lower levels of systemic F₂-isoprostane levels despite their predisposition to obesity and type 2 diabetes. The review summarizes new findings from epidemiological studies and a novel interpretation of metabolic determinants of systemic F₂-isoprostane levels as a favorable phenotype. Multiple observations indicate that systemic F₂-isoprostane levels reflect intensity of oxidative metabolism, a major endogenous source of reactive oxygen species, and specifically, the intensity of fat utilization. Evidence from multiple human studies proposes that targeting fat metabolism can be a productive race-specific strategy to address the existing racial health disparities. Urinary F₂-isoprostanes may provide the basis for targeted interventions to prevent obesity and type 2 diabetes among populations of African descent.

Factors Associated With Long-Term Weight Loss Following Bariatric Surgery Using 2 Methods for Repeated Measures Analysis

We used electronic health record data from 162 patients enrolled in the NUgene Project (2002-2013) to determine demographic factors associated with long-term (from 1 to up to 9.5 (mean = 5.6) years) weight loss following Roux-en-Y gastric bypass surgery. Ninety-nine (61.1%) patients self-reported white, and 63 (38.9%) self-reported black, mixed, or missing race. The average percent weight loss was -33.4% (standard deviation, 9.3) at 1 year after surgery and -30.7% (standard deviation, 12.5) at the last follow-up point. We used linear mixed and semiparametric trajectory models to test the association of surgical and demographic factors (height, surgery age, surgery weight, surgery body mass index, marital status, sex, educational level, site, International Classification of Diseases code, Current Procedural Terminology code, Hispanic ethnicity, and self-reported race) with long-term percent weight loss and pattern of weight loss. We found that black, mixed, and missing races (combined) in comparison with white race were associated with a decreased percent weight loss of -4.31% (95% confidence interval: -7.30, -1.32) and were less likely to have higher and sustained percent weight loss (P = 0.04). We also found that less obese patients were less likely to have higher and sustained percent weight loss (P = 0.01). These findings may be helpful to patients in setting expectations after weight loss surgery.