109 hospitals submitted data on 28,616 patients, from 7/2007 to 9/2010, which were included for this analysis. 22,365 cases from Level I hospitals, 2,661 from Level II hospitals and 3,590 cases from Outpatient centers. 944 cases were LSG, 12,193 were LAGBs, 14,491 were LRYGB, and 988 were ORYGB. As shown in , the numbers of LSGs has risen consistently over time, with LSGs making up 7.8% of primary bariatric operations collected at accredited centers over the most recent time period of January 1, 2010 to September 1, 2010. As the LSG has been introduced, the percentage of LRYGB has decreased from 62% of primary bariatric procedures performed to 44%, while the percentage of LAGB has risen form 32% to 46%. Based on this data at accredited centers, the LAGB now surpasses the LRYGB as the most common surgical procedure performed: 46% vs. 44%.
Increasing incidence of Sleeve Gastrectomy.
Patient characteristics are shown in , according to procedure type. Patients undergoing LSG have a higher percentage of super obesity (BMI>50) at 30.2%, nearly double that of LAGB (16.42%), and higher than LRYGB (25.95%). LSG also has the lowest percentage in the 40-50 BMI range, compared to the other procedures. This perhaps reflects the current teachings for the use of LSG for the super-obese as a potential staged procedure, or for the lower BMI patients. Compared to patients undergoing LAGB, patients undergoing LSG in general are heavier, with a higher percentage of all obesity related diseases and other comorbid conditions, except for smoking status. Compared to LRYGB, LSG has a lower percentage of diabetics, GERD, gallstones, smokers, dialysis but comparable percentages of patients in most other characteristics. There are a higher percentage of patients with COPD and male patients in the LSG group.
Patient Characteristics of 28,616 undergoing bariatric surgery at ACS-BSCN accredited centers.
LSG patients also have the highest percentage of patients who have had previous operations at 8.26%, even higher than for 3.24% for ORYGB, reflecting another potential relative indication for a sleeve gastrectomy (or potentially a specific way to get approved coverage for this procedure).
Overall 30-day mortality for this combined cohort of primary bariatric procedures was 0.12%. The rate of postoperative occurrences following LSG, lies between those for the LAGB, which has lower rates, and the LRYGB, which has higher rates, for all aggregated outcomes: mortality, morbidity, readmission, and reoperation rates, though not all comparisons are statistically significant. () Statistically significant findings are that the LSG has higher 30-morbidity, readmission and reoperation/intervention rates compared to the band, and lower reoperation/intervention rate compared to the bypass.
Thirty-day univariate outcomes by procedure type in 28,616 patients undergoing bariatric surgery at ACS-BSCN accredited centers.
Conversion rate, determined by the percentage of cases that were started laparoscopically and then converted to open, was 0.96% for the LSG. This is more than the LAGB rate of 0.25%, but less than the LRYGB rate of 1.4% (p<0.001). The only aggregated outcome where the sleeve is not positioned between the band and the bypass is the mean length of stay which is highest for LSG.
Compared to the LAGB, the LSG has statistically higher rates for peripheral nerve injury, pulmonary embolism, pneumonia, unplanned intubation, renal insufficiency, urinary tract infection, organ space infection, and sepsis. () Compared to the LRYGB, the LSG has higher rates of organ space infection, renal insufficiency, and sepsis but lower rates of ventilator dependence.
Bariatric specific postoperative occurrences requiring readmission, reoperation or an intervention within 30-days are listed in . Compared to the LAGB, LSG has a higher rate of anastomotic/staple line leaks, fluid/electrolyte/nutrition problems, strictures, infection/fevers, pulmonary embolism, bleeding and events not otherwise specified. Compared to LRYGB, LSG has a comparable rate of nearly all postoperative bariatric specific occurrences requiring readmission, reoperation or an intervention, except for a lower rate of stricture, intestinal obstruction, and anastomotic ulcer.
Bariatric specific complication rates requiring a reoperation and/or readmission by procedure type at ACS-BSCN accredited centers.
Risk adjusted outcomes
Risk adjusted modeling for mortality shows no significant differences between the procedures. () The statistically significant increased mortality of ORYGB is no longer significant when the sicker patients having ORYGB are taken into consideration. The remainder of the statistically significant findings from the univariate outcomes retains their significance after risk adjustment. In general, risk adjusted results continue to show LSG postoperative outcomes positioned between the LAGB and the LRYGB: the LSG has significantly higher rates or risk-adjusted morbidity, readmission and reoperation/intervention rates compared to the LAGB, and significantly lower rates of risk-adjusted reoperation/intervention rates compared to the LRYGB.
Risk-adjusted outcomes of 28,616 cases performed at ACS-BSCN accredited centers.
Reductions in Weight
Absolute reduction in BMI by procedure type is shown in . For LSG patients, the average reduction in BMI is 3.36 kg/m2 at 30 days, 8.75 kg/m2 at 6-months and 11.87 kg/m2 one-year. In comparison, the LAGB has a BMI reduction of 2.45, 5.02 and 7.05 kg/m2 at 30-day, 6-months and one-year, and the LRYGB has a BMI reduction of 3.76, 10.82 and 15.34 kg/m2 at 30 days, 6 months and one-year. Therefore, the absolute reduction in BMI following the LSG is less than the weight loss following the LRYGB/ORYGB but greater than the weight loss after the LAGB. () These findings are statistically significant at the 6-month and one-year intervals studied, however the impact of these findings is limited by the small number of LSG cases with data available at the one-year interval: only 52 cases currently have data available at one-year, despite a follow-up rate of 70.2%.
Reduction in Weight-related Comorbidities
In addition to changes in weight, five weight-related comorbidities are tracked over time as a metric for clinical effectiveness of these procedures. These include: diabetes, hypertension, hyperlipidemia, obstructive sleep apnea, and gastroesophageal reflux disease (GERD). The reductions in comorbidities over time for each procedure and for each comorbidity are shown in the five graphs in . For patients who are diabetic at baseline, 55% have their diabetes resolve or improve one year after the LSG, compared to 44% for the LAGB and 83% for the LRYGB. For patients who are hypertensive at baseline, 68% have their hypertension resolve or improve one year after the LSG, compared to 44% for the LAGB and 79% for the LRYGB. For patients who have hyperlipidemia at baseline, 35% have their hyperlipidemia resolve one year after the LSG, compared to 33% for the LAGB and 66% for the LRYGB. For patients who have obstructive sleep apnea at baseline, 62% have their obstructive sleep apnea resolve one year after the LSG, compared to 38% for the LAGB and 66% for the LRYGB. For patients who have GERD at baseline, 50% have their GERD resolve one year after the LSG, compared to 64% for the LAGB and 70% for the LRYGB. Overall, the clinical effectiveness for the LSG is positioned between the band and the bypass for diabetes, hypertension, sleep apnea, and hyperlipidemia. However, LSG appears less effective than both the band and the bypass for GERD. Again, statistical significance as shown on the graphs in is limited by the small number of patients with the disease who had a LSG with one year follow-up, despite follow-up rates exceeding 70%: 22 for DM, 38 for HTN, 17 for hyperlipidemia, 26 for OSA, and 22 for GERD. These small numbers limits the power of the current data set to identify significance, or to draw any substantive conclusions from these early observations.
Reduction in Obesity Related Diseases
Percent follow-up for weight is quite good – 70.2% at one year for LSG, and similar rates for the LAGB (74.3%) LRYGB (70.7%) and ORYGB (62.7%). Similar rates of follow-up are identified for the weight-related comorbidities ().