No significant difference between costs, mortality and re-admissions between RYGB and SG

Updated: Oct 25

Researchers from Canada have reported that four-year health care expenditures, all-cause mortality, and number of hospital admissions associated with Roux-en-Y gastric bypass (RYGB) did not significantly differ from those for sleeve gastrectomy (SG). Patients in the RYGB cohort underwent fewer subsequent bariatric procedures, whereas the number of subsequent non-elective admissions was higher with RYGB. The results were published in the paper, ‘Comparison of 4-Year Health Care Expenditures Associated With Roux-en-Y Gastric Bypass vs Sleeve Gastrectomy’, JAMA Network Open.

For their study, the researchers included 6,301 RYGB and 926 SG patients who are part of the Ontario Bariatric Registry. The 1:1 matched study cohorts consisted of 1,624 patients (812 per cohort). The primary study outcome was health care expenditures and secondary outcomes included the number of subsequent hospitalisations and bariatric procedures (ie, sleeve gastrectomy, RYGB or duodenal switch, as well as all-cause mortality.


The variables included in the score were age, sex, BMI, year of surgery, geographical location, census neighbourhood income quintile, Ontario Marginalization Index, number of major Aggregated Diagnostic Groups (ADG), potentially confounding chronic medical conditions derived from validated administrative data case definitions (eg, chronic kidney disease, coronary artery disease, type 2 diabetes, hypertension, hypercholesterolemia, and mood and anxiety disorders), total health care expenditures in the five years preceding the index surgery date and number of days in the hospital and number of emergency department visits in the 365 days preceding the index date.


Most of the subjects were female (n=1,242, 76.5%) and the mean age was 47.9 years for the RYGB cohort and 48.1 years for the SG cohort. Each cohort included 621 women (76.5%), 191 men (23.5%) and 310 patients with type 2 diabetes (38.2%). The mean BMI was 51.9 for both cohorts. A total of 97.4% of subjects achieved the minimum 48 months of follow-up (791 of 812 in each group). The 4-year all-cause mortality rate was 2.2% (18 of 812) for the SG group and 1.5% (12 of 812) for the RYGB group (p=0.26).


The investigators reported that the mean health care expenditures during the four years after RYGB surgery were not significantly different from those after SG (US$33,682 vs US$33,948 respectively; p=0.86). However, when the analyses were stratified by time, the mean health care expenditures associated with the surgical admission were relatively higher for RYGB (US$12,888 vs. SG $12,231 p=0.02). In addition, there were no statistically significant differences in mean health care expenditures between RYGB and SG from discharge to the end of year one, tw0, three or four after the procedure.


Interestingly, costs associated with hospitalisation (RYGB, 47%; sleeve gastrectomy, 49%) and specialist visits (RYGB, 27%; sleeve gastrectomy, 24%) accounted for almost 75% of the four-year health care costs associated with each procedure.


Approximately 50% of patients had at least one readmission (RYGB, 370 of 812 [45.6%]; sleeve gastrectomy, 385 of 812 [47.4%]; p=0.44) for a total of 754 and 669 hospital readmissions for the RYGB and sleeve gastrectomy cohorts, respectively (0=0.11), at four years. Non-elective hospitalisations four years after the procedure occurred more with RYGB vs sleeve gastrectomy (472 vs 339; p=0.002). More SG subjects had revisional procedures (37 of 812 [4.6%]) compared with RYGB (eight of 812 [1.0%]; p<0.001). Eleven of 37 SG subjects who had revisional procedures had a BMI>60.


There was no association between the type of bariatric surgery procedure and four-year overall health care costs. Although, SG was associated with a 7% increase in four-year costs for elective hospitalisation and a 7% decrease in physician costs (after controlling for baseline characteristics. Other results indicated that a history of coronary artery disease (35% increase), chronic kidney disease (54% increase) and mental health admissions (67% increase) were the main factors contributing to the overall and individual cost components.

“To our knowledge, this is the first study comparing long-term health care expenditures among patients undergoing RYGB vs SG…We found a positive association between sleeve gastrectomy and the four-year costs associated with elective hospitalisations and a negative association with four-year physician costs,” the authors noted. “We identified important patient-level factors associated with health care expenditures, such as history of chronic kidney disease, coronary artery disease, and mental illness admissions, which need further investigation to better understand the costs and outcomes associated with these groups of patients.”

Further information

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