Learning Curve for Robotic-Assisted Cholecystectomy.

This cohort study evaluates the learning curve for robotic-assisted cholecystectomy among US surgeons from 2010 through 2019.

Comparative Safety of Robotic-Assisted vs Laparoscopic Cholecystectomy.

Importance: Robotic-assisted cholecystectomy is rapidly being adopted into practice, partly based on the belief that it offers specific technical and safety advantages over traditional laparoscopic surgery. Whether robotic-assisted cholecystectomy is safer than laparoscopic cholecystectomy remains unclear. Objective: To determine the uptake of robotic-assisted cholecystectomy and to analyze its comparative safety vs laparoscopic cholecystectomy. Design, Setting, and Participants: This retrospective cohort study used Medicare administrative claims data for nonfederal acute care hospitals from January 1, 2010, to December 31, 2019. Participants included 1 026 088 fee-for-service Medicare beneficiaries 66 to 99 years of age who underwent cholecystectomy with continuous Medicare coverage for 3 months before and 12 months after surgery. Data were analyzed August 17, 2022, to June 1, 2023. Exposure: Surgical technique used to perform cholecystectomy: robotic-assisted vs laparoscopic approaches. Main Outcomes and Measures: The primary outcome was rate of bile duct injury requiring definitive surgical reconstruction within 1 year after cholecystectomy. Secondary outcomes were composite outcome of bile duct injury requiring less-invasive postoperative surgical or endoscopic biliary interventions, and overall incidence of 30-day complications. Multivariable logistic analysis was performed adjusting for patient factors and clustered within hospital referral regions. An instrumental variable analysis was performed, leveraging regional variation in the adoption of robotic-assisted cholecystectomy within hospital referral regions over time, to account for potential confounding from unmeasured differences between treatment groups. Results: A total of 1 026 088 patients (mean [SD] age, 72 [12.0] years; 53.3% women) were included in the study. The use of robotic-assisted cholecystectomy increased 37-fold from 211 of 147 341 patients (0.1%) in 2010 to 6507 of 125 211 patients (5.2%) in 2019. Compared with laparoscopic cholecystectomy, robotic-assisted cholecystectomy was associated with a higher rate of bile duct injury necessitating a definitive operative repair within 1 year (0.7% vs 0.2%; relative risk [RR], 3.16 [95% CI, 2.57-3.75]). Robotic-assisted cholecystectomy was also associated with a higher rate of postoperative biliary interventions, such as endoscopic stenting (7.4% vs 6.0%; RR, 1.25 [95% CI, 1.16-1.33]). There was no significant difference in overall 30-day complication rates between the 2 procedures. The instrumental variable analysis, which was designed to account for potential unmeasured differences in treatment groups, also showed that robotic-assisted cholecystectomy was associated with a higher rate of bile duct injury (0.4% vs 0.2%; RR, 1.88 [95% CI, 1.14-2.63]). Conclusions and Relevance: This cohort study's finding of significantly higher rates of bile duct injury with robotic-assisted cholecystectomy compared with laparoscopic cholecystectomy suggests that the utility of robotic-assisted cholecystectomy should be reconsidered, given the existence of an already minimally invasive, predictably safe laparoscopic approach.

Comparison of safety and healthcare utilization following sleeve gastrectomy or gastric bypass among medicare beneficiaries using sex as a biologic variable.

BACKGROUND: Bariatric surgery is a common operation, but differences in outcomes between males and females are unknown. OBJECTIVES: To compare the risk of mortality, complications, reintervention, and healthcare utilization after sleeve gastrectomy or gastric bypass using sex as a biologic variable. SETTING: United States. METHODS: Retrospective cohort study of adults undergoing sleeve gastrectomy or gastric bypass from January 1, 2012 to December 31, 2018 using Medicare claims data. We performed a heterogeneity of treatment effect analysis to determine the impact of sleeve gastrectomy versus gastric bypass comparing males to females. The primary outcome was safety (mortality, complications, and reinterventions) up to 5 years after surgery. The secondary outcome was healthcare utilization (hospitalization and emergency department use). RESULTS: Among 95,405 patients the majority (n = 71,348; 74.8%) were female and most (n = 57,008; 59.8%) underwent sleeve gastrectomy. For all patients, compared to gastric bypass, sleeve gastrectomy was associated with a lower risk of complications and reintervention but a higher risk of revision. Compared to gastric bypass, sleeve gastrectomy was associated with a lower risk of mortality for females (adjusted hazard ratio .86, 95% CI .75-.96) but not males. We found no difference in procedure treatment effect by sex for mortality, hospitalization, emergency department use, or overall reintervention when comparing sleeve to gastric bypass. CONCLUSIONS: Females and males have similar outcomes following bariatric surgery. Females have a lower risk of complications but a higher risk of reintervention. Decisions surrounding treatment for this common procedure should be tailored to include a discussion of sex-specific differences in treatment outcome.

Trends in Use of Robotic Surgery for Privately Insured Patients and Medicare Fee-for-Service Beneficiaries.

This cohort study evaluates trends in the adoption of robotic surgery among Medicare beneficiaries and privately insured patients for common general surgical procedures.

The intersection of race and ethnicity, gender, and primary diagnosis on lung transplantation outcomes.

BACKGROUND: Reducing racial disparities in lung transplant outcomes is a current priority of providers, policymakers, and lung transplant centers. It is unknown how the combined effect of race and ethnicity, gender, and diagnosis group is associated with differences in 1-year mortality and 5-year survival. METHODS: This is a longitudinal cohort study using Standard Transplant Analysis Research files from the United Network for organ sharing. A total of 25,444 patients undergoing first time lung transplantation between 2006 and 2019 in the United States. The primary exposures were lung transplant recipient race and ethnicity, gender, and primary diagnosis group at listing. Multivariable regression models and cox-proportional hazards models were used to determine adjusted 1-year mortality and 5-year survival. RESULTS: Overall, 25,444 lung transplant patients were included in the cohort including 15,160 (59.6%) men, 21,345 (83.9%) White, 2,318 (9.1%), Black and Hispanic/Latino (7.0%). Overall, men had a significant higher 1-year mortality than women (11.87%; 95% CI 11.07-12.67 vs 12.82%; 95% CI 12.20%-13.44%). Black women had the highest mortality of all race and gender combinations (14.51%; 95% CI 12.15%-16.87%). Black patients with pulmonary vascular disease had the highest 1-year mortality (19.77%; 95% CI 12.46%-27.08%) while Hispanic/Latino patients with obstructive lung disease had the lowest (7.42%; 95% CI 2.8%-12.05%). 5-year adjusted survival was highest among Hispanic/Latino patients (62.32%) compared to Black (57.59%) and White patients (57.82%). CONCLUSIONS: There are significant differences in 1-year and 5-year mortality between and within racial and ethnic groups depending on gender and primary diagnosis. This demonstrates the impact of social and clinical factors on lung transplant outcomes.

Comparative Outcomes of Groin Hernia Repair by Sex Among Medicare Beneficiaries.

OBJECTIVE: To compare the rates of operative recurrence between male and female patients undergoing groin hernia repair. BACKGROUND DATA: Groin hernia repair is common but understudied in females. Limited prior work demonstrates worse outcomes among females. METHODS: Using Medicare claims, we performed a retrospective cohort study of adult patients who underwent elective groin hernia repair between January 1, 2010 and December 31, 2017. We used a Cox proportional hazards model to evaluate the risk of operative recurrence up to 5 years following the index operation. Secondary outcomes included 30-day complications following surgery. RESULTS: Among 118,119 patients, females comprised the minority of patients (n=16,056, 13.6%). Compared with males, female patients were older (74.8 vs. 71.9 y, P <0.01), more often white (89.5% vs. 86.7%, P <0.01), and had a higher prevalence of nearly all measured comorbidities. In the multivariable Cox proportional hazards model, we found that female patients had a significantly lower risk of operative recurrence at 5-year follow-up compared with males (aHR 0.70, 95% CI 0.60-0.82). The estimated cumulative incidence of recurrence was lower among females at all time points: 1 year [0.68% (0.67-0.68) vs. 0.88% (0.88-0.89)], 3 years [1.91% (1.89-1.92) vs. 2.49% (2.47-2.5)], and 5 years [2.85% (2.82-2.88) vs. 3.7% (3.68-3.75)]. We found no significant difference in the 30-day risk of complications. CONCLUSIONS: We found that female patients experienced a lower risk of operative hernia recurrence following elective groin hernia repair, which is contrary to what is often reported in the literature. However, the risk of operative recurrence was low overall, indicating excellent surgical outcomes among older adults for this common surgical condition.

Treatment patterns and survival in older adults with unresected nonmetastatic biliary tract cancers.

INTRODUCTION: The optimal treatment for unresected nonmetastatic biliary tract cancer (uBTC) is not well-established. The objective of this study was to analyze the treatment patterns and compare the differences in overall survival (OS) between different treatment strategies amongst older adults with uBTC. MATERIALS AND METHODS: We identified patients aged ≥65 years with uBTC using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database (2004-2015). Treatments were classified into chemotherapy, chemoradiotherapy, and radiotherapy. The primary outcome was OS. The differences in OS were analyzed using Kaplan-Meier curves and multivariable Cox proportional hazard regression. RESULTS: A total of 4352 patients with uBTC were included. The median age was 80 years and median OS was 4.1 months. Most patients (67.3%, n = 2931) received no treatment, 19.1% chemotherapy (n = 833), 8.1% chemoradiotherapy (n = 354), and 5.4% radiotherapy alone (n = 234). Patients receiving no treatment were older and had more comorbidities. Chemotherapy was associated with significantly longer OS than no treatment in uBTC (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.79-0.95), but no difference was found in the subgroups of intrahepatic cholangiocarcinoma (iCCA; HR 0.87, 95% CI 0.75-1.00) and gallbladder carcinoma (GBC; HR 1.09, 95% CI 0.86-1.39). In the sensitivity analyses, capecitabine-based chemoradiotherapy showed significantly longer OS in uBTC compared to chemotherapy (adjusted HR 0.71, 95% CI 0.53-0.95). DISCUSSION: A minority of older patients with uBTC receive systemic treatments. Chemotherapy was associated with longer OS compared to no treatment in uBTC, but not in the subgroups of iCCA and GBC. The efficacy of chemoradiotherapy, especially in perihilar cholangiocarcinoma using capecitabine-based chemoradiotherapy, may be further evaluated in prospective clinical trials.

Contemporary Outcomes of Elective Parastomal Hernia Repair in Older Adults.

Importance: Parastomal hernia is a challenging complication following ostomy creation; however, the incidence and long-term outcomes after elective parastomal hernia repair are poorly characterized. Objective: To describe the incidence and long-term outcomes after elective parastomal hernia repair. Design, Setting, and Participants: Using 100% Medicare claims, a retrospective cohort study of adult patients who underwent elective parastomal hernia repair between January 1, 2007, and December 31, 2015, was performed. Logistic regression and Cox proportional hazards models were used to evaluate mortality, complications, readmission, and reoperation after surgery. Analysis took place between February and May 2022. Exposures: Parastomal hernia repair without ostomy resiting, parastomal hernia repair with ostomy resiting, and parastomal hernia repair with ostomy reversal. Main Outcomes and Measures: Mortality, complications, and readmission within 30 days of surgery and reoperation for recurrence (parastomal or incisional hernia repair) up to 5 years after surgery. Results: A total of 17 625 patients underwent elective parastomal hernia repair (mean [SD] age, 73.3 [9.1] years; 10 059 female individuals [57.1%]). Overall, 7315 patients (41.5%) underwent parastomal hernia repair without ostomy resiting, 2744 (15.6%) underwent parastomal hernia repair with ostomy resiting, and 7566 (42.9%) underwent parastomal hernia repair with ostomy reversal. In the 30 days after surgery, 676 patients (3.8%) died, 7088 (40.2%) had a complication, and 1740 (9.9%) were readmitted. The overall adjusted 5-year cumulative incidence of reoperation was 21.1% and was highest for patients who underwent parastomal hernia repair with ostomy resiting (25.3% [95% CI, 25.2%-25.4%]) compared with patients who underwent parastomal hernia repair with ostomy reversal (18.8% [95% CI, 18.7%-18.8%]). Among patients whose ostomy was not reversed, the hazard of repeat parastomal hernia repair was the same for patients whose ostomy was resited vs those whose ostomy was not resited (adjusted hazard ratio, 0.93 [95% CI, 0.81-1.06]). Conclusions and Relevance: In this study, more than 1 in 5 patients underwent another parastomal or incisional hernia repair within 5 years of surgery. Although this was lowest for patients who underwent ostomy reversal at their index operation, ostomy resiting was not superior to local repair. Understanding the long-term outcomes of this common elective operation may help inform decision-making between patients and surgeons regarding appropriate operative approach and timing of surgery.

Births After Bariatric Surgery in the United States: Incidence, Obstetric Outcomes, and Reinterventions.

OBJECTIVE: To characterize incidence and outcomes for bariatric surgery patients who give birth. BACKGROUND: Patients of childbearing age comprise 65% of bariatric surgery patients in the United States, yet data on how often patients conceive and obstetric outcomes are limited. METHODS: Using the IBM MarketScan database, we performed a retrospective cohort study of female patients ages 18 to 52 undergoing laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass from 2011 to 2017. We determined the incidence of births in the first 2 years after bariatric surgery using Kaplan-Meier estimates. We then restricted the cohort to those with a full 2-year follow-up to examine obstetric outcomes and bariatric-related reinterventions. We reported event rates of adverse obstetric outcomes and delivery type. Adverse obstetric outcomes include pregnancy complications, severe maternal morbidity, and delivery complications. We performed multivariable logistic regression to examine associations between birth and risk of reinterventions. RESULTS: Of 69,503 patients who underwent bariatric surgery, 1464 gave birth. The incidence rate was 2.5 births per 100 patients in the 2 years after surgery. Overall, 85% of births occurred within 21 months after surgery. For 38,922 patients with full 2-year follow-up, adverse obstetric event rates were 4.5% for gestational diabetes and 14.2% for hypertensive disorders. In all, 48.5% were first-time cesarean deliveries. Almost all reinterventions during pregnancy were biliary. Multivariable logistic regression analysis showed no association between postbariatric birth and reintervention rate (odds ratio: 0.93, 95% confidence interval: 0.78-1.12). CONCLUSIONS: In this first national US cohort, we find giving birth was common in the first 2 years after bariatric surgery and was not associated with an increased risk of reinterventions. Clinicians should consider shifting the dialogue surrounding pregnancy after surgery to shared decision-making with maternal safety as one component.

The Measurement Reliability of Complications and Patient Satisfaction After Common Surgical Procedures.

OBJECTIVE: To evaluate the reliability of surgeon outcomes. BACKGROUND: Surgeons' outcomes are now widely used in public reporting and value-based reimbursement, but the reliability of these measures continues to raise concerns. METHODS: We performed a retrospective study of surgeons performing cholecystectomy, colectomy, and hernia repair on adult patients between January 1, 2017, and December 31, 2020. Outcomes were risk-adjusted rates of complications and high patient satisfaction. We estimated the reliability of each outcome, its relationship with case volume, and the number of surgeons who reached an acceptable level of reliability (≥0.70). RESULTS: A total of 23,533 patients with a mean age of 56.8 (16.2) years and 10,191 (43.3%) females underwent operations by 333 surgeons. Risk-adjusted complication rate was 2.5% [95% confidence interval (CI): 2.2%-2.8%] and risk-adjusted high satisfaction rate was 79.9% (95% CI: 78.7%-81.0%). The reliability of the complication rate was 0.27 (95% CI: 0.25-0.29) and the reliability of the high satisfaction rate was 0.53 (95% CI: 0.50-0.55). Reliability increased with case volume; however, only 5 (1.5%) surgeons performed enough cases to reach acceptable reliability for their complication rate, while 86 (25.8%) surgeons reached acceptable reliability for their patient satisfaction rate. After adjustment for reliability, the range of complication rates decreased 29-fold from 0% to 14.3% to 2.4% to 2.9%, and the range of patient satisfaction decreased 2.6-fold from 25.3% to 100.0% to 64.9% to 92.4%. CONCLUSIONS: Among surgeons performing common operations, complications and patient satisfaction had relatively low reliability. Although reliability increased with volume, most surgeons had insufficient case volume to achieve acceptable reliability of their outcomes. As such, these measures likely offer little to no meaningful information to inform decision-making.

Trends in Surgical Technique and Outcomes of Ventral Hernia Repair in The United States.

OBJECTIVE: To describe national trends in surgical technique and rates of reoperation for recurrence for patients undergoing ventral hernia repair (VHR) in the United States. BACKGROUND: Surgical options for VHR, including minimally invasive approaches, mesh implantation, and myofascial release, have expanded considerably over the past 2 decades. Their dissemination and impact on population-level outcomes is not well characterized. METHODS: We conducted a retrospective cohort study of Medicare beneficiaries undergoing elective, inpatient umbilical, ventral, or incisional hernia repair between 2007 and 2015. Cox proportional hazards models were used to estimate the adjusted proportion of patients who remained free from reoperation for hernia recurrence up to 5 years after surgery. RESULTS: One hundred fort-one thousand two hundred sixty-one patients underwent VHR during the study period. Between 2007 and 2018, the use of minimally invasive surgery increased from 2.1% to 22.2%, mesh use increased from 63.2% to 72.5%, and myofascial release increased from 1.8% to 16.3%. Overall, the 5-year incidence of reoperation for recurrence was 14.1% [95% confidence interval (CI) 14.0%-14.1%]. Over time, patients were more likely to remain free from reoperation for hernia recurrence 5 years after surgery [2007-2009 reoperation-free survival: 84.9% (95% CI 84.8%-84.9%); 2010-2012 reoperation-free survival: 85.7% (95% CI 85.6%-85.7%); 2013-2015 reoperation-free survival: 87.8% (95% CI 87.7%-87.9%)]. CONCLUSIONS: The surgical treatment of ventral and incisional hernias has evolved in recent decades, with more patients undergoing minimally invasive repair, receiving mesh, and undergoing myofascial release. Although our analysis does not address causality, rates of reoperation for hernia recurrence improved slightly contemporaneous with changes in surgical technique.

Out-of-pocket Costs for Commercially-insured Patients in the Years Following Bariatric Surgery: Sleeve Gastrectomy Versus Roux-en-Y Gastric Bypass.

OBJECTIVE: To compare out-of-pocket (OOP) costs for patients up to 3 years after bariatric surgery in a large, commercially-insured population. SUMMARY OF BACKGROUND DATA: More information on OOP costs following bariatric surgery may affect patients' procedure choice. METHODS: Retrospective study using the IBM MarketScan commercial claims database, representing patients nationally who underwent laparoscopic sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) January 1, 2011 to December 31, 2017. We compared total OOP costs after the surgical episode between the 2 procedures using difference-in-differences analysis adjusting for demographics, comorbidities, operative year, and insurance type. RESULTS: Of 63,674 patients, 64% underwent SG and 36% underwent RYGB. Adjusted OOP costs after SG were $1083, $1236, and $1266 postoperative years 1, 2, and 3. For RYGB, adjusted OOP costs were $1228, $1377, and $1369. In our primary analysis, SG OOP costs were $122 (95% confidence interval [CI]: -$155 to -$90) less than RYGB year 1. This difference remained consistent at -$119 (95%CI: -$158 to -$79) year 2 and -$80 (95%CI: -$127 to -$35) year 3. These amounts were equivalent to relative differences of -7%, -7%, and -5% years 1, 2, and 3. Plan features contributing the most to differences were co-insurance years 1, 2, and 3.The largest clinical contributors to differences were endoscopy and outpatient care year 1, outpatient care year 2, and emergency department use year 3. CONCLUSIONS: Our study is the first to examine the association between bariatric surgery procedure and OOP costs. Differences between procedures were approximately $100 per year which may be an important factor for some patients deciding whether to pursue SG or gastric bypass.

Comparative Safety of Sleeve Gastrectomy and Gastric Bypass up to 5 Years After Surgery in Patients With Medicaid.

OBJECTIVE: Compare adverse outcomes up to 5 years after sleeve gastrectomy and gastric bypass in patients with Medicaid. BACKGROUND: Sleeve gastrectomy is the most common bariatric operation among patients with Medicaid; however, its long-term safety in this population is unknown. METHODS: Using Medicaid claims, we performed a retrospective cohort study of adult patients who underwent sleeve gastrectomy or gastric bypass from January 1, 2012, to December 31, 2018. Instrumental variables survival analysis was used to estimate the cumulative incidence and heterogeneity of outcomes up to 5 years after surgery. RESULTS: Among 132,788 patients with Medicaid, 84,717 (63.8%) underwent sleeve gastrectomy and 48,071 (36.2%) underwent gastric bypass. A total of 69,225 (52.1%) patients were White, 33,833 (25.5%) were Black, and 29,730 (22.4%) were Hispanic. Compared with gastric bypass, sleeve gastrectomy was associated with a lower 5-year cumulative incidence of mortality (1.29% vs 2.15%), complications (11.5% vs 16.2%), hospitalization (43.7% vs 53.7%), emergency department (ED) use (61.6% vs 68.2%), and reoperation (18.5% vs 22.8%), but a higher cumulative incidence of revision (3.3% vs 2.0%). Compared with White patients, the magnitude of the difference between sleeve and bypass was smaller among Black patients for ED use [5-y adjusted hazard ratios: 1.01; 95% confidence interval (CI), 0.94-1.08 vs 0.94 (95% CI, 0.88-1.00), P <0.001] and Hispanic patients for reoperation [5-y adjusted hazard ratios: 0.95 (95% CI, 0.86-1.05) vs 0.76 (95% CI, 0.69-0.83), P <0.001]. CONCLUSIONS: Among patients with Medicaid undergoing bariatric surgery, sleeve gastrectomy was associated with a lower risk of mortality, complications, hospitalization, ED use, and reoperations, but a higher risk of revision compared with gastric bypass. Although the difference between sleeve and bypass was generally similar among White, Black, and Hispanic patients, the magnitude of this difference was smaller among Black patients for ED use and Hispanic patients for reoperation.

Variation of ventral and incisional hernia repairs in kidney transplant recipients.

INTRODUCTION: As survivorship following kidney transplant continues to improve, so does the probability of intervening on common surgical conditions, such as ventral or incisional hernia, in this population. Ventral hernia management is known to vary across institutions and this variation has an impact on patient outcomes. We sought to evaluate hospital level variation of ventral or incisional hernia repair (VIHR) in the kidney transplant population. METHODS: We performed a retrospective review of 100% inpatient Medicare claims to identify patients who underwent kidney transplant between 2007 and 2018. The primary outcome was 1- and 3-year ventral or incisional risk- and reliability-adjusted VIHR rates. Patient and hospital characteristics were evaluated across risk- and reliability-adjusted VIHR rate tertiles. Models were adjusted for age, sex, race, and Elixhauser comorbidities. RESULTS: Overall, 139,741 patients underwent kidney transplant during the study period with a mean age (SD) of 51.6 (13.7) years. 84,717 (60.6%) were male, and 72,657 (52.0%) were white. Median follow up time was 5.4 years. 2098 (1.50%) patients underwent VIHR. the 1 year risk- and reliability-adjusted hernia repair rates were 0.49% (95% Conf idence Interval (CI) 0.48-0.51, range 0.31-0.59) in tertile 1, 0.63% (95% CI 0.62-0.63, range 0.59-0.68) in tertile 2, and 0.98 (95% CI 0.91-1.05, range 0.68-2.94) in tertile 3. Accordingly, compared to hospitals in tertile 1, the odds of post-transplant hernia repair tertile 2 hospitals were 1.78 (95% CI 1.37-2.31) and at tertile 3 hospitals 3.53 (95% CI 2.87-4.33). CONCLUSIONS: In a large cohort of Medicare patients undergoing kidney transplant, the overall cumulative incidence of hernia repair varied substantially across hospital tertiles. Patient and hospital characteristics varied across tertile, most notably in diabetes and obesity. Future research is needed to understand if program and surgeon level factors are contributing to the observed variation in treatment of this common disease.

Health Care Use and Adverse Events After Sleeve Gastrectomy and Gastric Bypass Among Adolescents With Severe Obesity Insured by Medicaid.

This study examines health care use and adverse events up to 5 years after bariatric surgery in adolescents with severe obesity insured by Medicaid.

Association of Insurance Coverage With Adoption of Sleeve Gastrectomy vs Gastric Bypass for Patients Undergoing Bariatric Surgery.

Importance: Instrumental variables can control for selection bias in observational research. However, valid instruments are challenging to identify. Objective: To evaluate regional variation in sleeve gastrectomy following insurance coverage implementation as an instrumental variable in comparative effectiveness research. Design, Setting, and Participants: This serial cross-sectional study included adult patients in a national Medicare claims database who underwent sleeve gastrectomy or Roux-en-Y gastric bypass from 2012 to 2017. Data analysis was performed from January to June 2021. Exposures: Laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass. Main Outcomes and Measures: The association of the instrumental variable with treatment (ie, undergoing sleeve gastrectomy), as well as mortality, complications, emergency department visits, hospitalization, reinterventions, and surgical revision. Results: A total of 76 077 patients underwent bariatric surgery, of whom 44 367 underwent sleeve gastrectomy (mean [SD] age, 56.9 [11.9] years; 32 559 [73.5%] women) and 31 710 underwent gastric bypass (mean (SD) age, 55.9 (11.8) years; 23 750 [74.9%] women). After insurance coverage initiation, there was substantial regional and temporal variation in adoption of sleeve gastrectomy. Prior-year state-level utilization of sleeve gastrectomy was highly associated with undergoing sleeve gastrectomy (Kleibergen-Paap Wald F statistic, 910.3). All but 2 patient characteristics (race and diagnosis of depression) were well-balanced between the top and bottom quartiles of the instrumental variable. Regarding 1-year outcomes, compared with patients undergoing gastric bypass, patients undergoing sleeve gastrectomy had a lower 1-year risk of mortality (0.9%; 95% CI, 0.8%-1.1% vs 1.7%; 95% CI, 1.3%-2.0%), complications (11.6%; 95% CI, 10.9%-12.3% vs 14.1%; 95% CI, 13.0%-15.3%), emergency department visits (48.3%; 95% CI, 46.9%-49.8% vs 53.6%; 95% CI, 52.3%-55.0%), hospitalization (23.4%; 95% CI, 22.4%-24.4% vs 26.5%; 95% CI, 25.1%-28.0%), and reinterventions (8.7%; 95% CI, 8.0%-9.4% vs 12.2%; 95% CI, 11.2%-13.3%). The risk of revision was not different between groups (0.6%; 95% CI, 0.3%-0.8% vs 0.4%; 95% CI, 0.3%-0.6%). Conclusions and Relevance: In this cross-sectional study of patients undergoing bariatric surgery, there was significant geographic variation in the use of sleeve gastrectomy following initiation of insurance coverage, which served as a strong instrument to compare 2 bariatric surgical procedures. This approach could be applied to other areas of health services research to serve as a complement to clinical trials.

Long-term comparative effectiveness of gastric bypass and sleeve gastrectomy on use of antireflux medication: a difference-in-differences analysis.

BACKGROUND: Gastroesophageal reflux (GERD) is common among patients with obesity who undergo bariatric surgery. Although gastric bypass and sleeve gastrectomy are the most common bariatric operations performed in the United States, their long-term comparative effectiveness on GERD medication use is unknown. OBJECTIVE: To compare the long-term effectiveness of gastric bypass and sleeve gastrectomy on use of antireflux medication. SETTING: National cohort undergoing inpatient bariatric surgery. METHODS: This is a retrospective study of Medicare beneficiaries undergoing gastric bypass and sleeve gastrectomy between January 1, 2012, and December 31, 2017. A difference-in-differences analysis was conducted to evaluate the differential change in antireflux medication use between groups before and after surgery. RESULTS: A total of 16,640 patients underwent gastric bypass, and 26,724 patients underwent sleeve gastrectomy. Before surgery, GERD medication use was higher among patients who underwent gastric bypass (62.4%; 95% confidence interval [CI]: 62.0%-63.7%) compared with patients who underwent sleeve gastrectomy (60.1%; 95% CI: 59.3%-60.9%). Five years after surgery, GERD medication use was lower in patients who underwent gastric bypass (47.8%; 95% CI: 46.3%-49.3%) compared with patients who underwent sleeve gastrectomy (53.7%; 95% CI: 50.5%-56.9%). The differential decrease from baseline GERD medication use was greater for patients who underwent gastric bypass at 2 years (-4.1 percentage points [pp]; 95% CI: -1.7 to -6.5 pp), 3 years (-4.3 pp; 95% CI: -1.6 to -7.0 pp), 4 years (-6.9 pp; 95% CI: -4.1 to -9.6 pp), and 5 years (-8.3 pp; 95% CI: -3.7 to 12.8 pp) after surgery. CONCLUSION: Though use of antireflux medication decreased following both procedures, gastric bypass was associated with a greater reduction in antireflux medication use 5 years after surgery compared with sleeve gastrectomy. Understanding the long-term comparative effectiveness of these common bariatric operations may better inform treatment decisions among patients and surgeons.

Surgeon Variation in the Application of Robotic Technique for Abdominal Hernia Repair: A Mixed-Methods Study.

INTRODUCTION: Although the utilization of robotic technique for abdominal hernia repair has increased rapidly, there is no consensus as to when it should be applied for optimal outcomes. High variability exists within surgeon practices regarding how they use this technology, and the factors that drive robotic utilization remain largely unknown. This study aims to explore the motivating factors associated with surgeons' decisions to utilize a robotic approach for abdominal hernia repair. METHODS: An exploratory mixed-methods approach was utilized. Surgeons who performed abdominal hernia repairs were interviewed to identify impactful themes motivating surgical approach. This informed a retrospective analysis of ventral hernia repairs performed in 2020 within the Michigan Surgical Quality Collaborative. Surgeon robotic utilization rates were calculated. Among selective robotic users, multivariable regression evaluated the patient and hernia factors associated with robotic utilization. RESULTS: Qualitative analysis of 21 interviews revealed three dominant themes in the decision to utilize robotic technology: access and resources, surgeon comfort, and market factors. Among 71 surgeons caring for 1174 hernia patients, robotic utilization rates ranged from 0% to 98% of cases. There were 27 surgeons identified as selective robotic users, who cared for 423 patients. Multivariable regression revealed that hernia location was the only factor associated with robotic technique, with non-midline hernias associated with a 4.47 (95% confidence interval 1.34-14.88) higher odds of robotic repair than epigastric hernias. CONCLUSIONS: Major drivers of robotic technique for hernia repair were found to be perceived benefits and availability, rather than patient or hernia characteristics. These data will contribute to an understanding of surgeon decision-making and help develop improvements to patient care.