PCORnet: Gastric banding patients at most risk of adverse events

Adjustable gastric banding (AGB) patients experienced the most risk of adverse events in general after surgery, although Roux-en-Y gastric bypass (RYGB) patients had a higher risk of operation and intervention but had less need for revision compared to sleeve gastrectomy, according to an analysis from the National Patient-Centered Clinical Research Network (PCORnet). The outcomes were featured in the paper, ‘Interventions and Operations after Bariatric Surgery in a Health Plan Research Network Cohort from the PCORnet, the National Patient-Centered Clinical Research Network’, published in Obesity Surgery.

In this observational cohort study, the researchers sought to compare the short- and long-term safety outcomes AGB, RYGB, and SG using data from the PCORnet Bariatric Study (PBS) between January 2006 and September 2015. The study compared short- (30-day composite adverse events) and long-term (intervention/operation, endoscopy, hospitalisation and mortality up to five years) safety outcomes associated with three bariatric surgical procedures. The primary long-term adverse event included subsequent operation or intervention (any additional bariatric procedure and abdominal procedures) with secondary long-term adverse events including subsequent endoscopy, revision, all-cause hospitalisation and all-cause death.

Outcomes

In total, 95,251 patients (mean age 44.2 (11.4) years, female (75.8%) underwent 34,240 (35.9%) AGB procedures, 36,206 (38.0%) underwent RYGB and 24,805 (26.0%) underwent SG. Patients in the RYGB group were older (44.9 vs. 43.7 years for SG, and 43.9 years for AGB) and had higher rates of diabetes (42.4%) and hypertension (70.4%). The median follow-up was 3.3 (1.4–5.0) years for AGB, 2.5 (1.0–4.6) years for RYGB and 1.1 (0.5–2.1) years for SG.

Within 30 days, 3.05% of AGB, 3.80% of RYGB and 2.78% of SG had the composite outcome. Larger proportions required intervention: 2.62% for AGB, 2.14% for RYGB and 1.71% for SG. The adjusted odds ratios for the composite outcome were significantly lower for AGB relative to RYGB (AOR, 0.81; 95% CI, 0.72–0.92; P<0.001) and SG (AOR, 0.80; 95% CI, 0.73–0.87; p<0.001). Compared to the RYGB group, the SG group had similar probability (AOR, 0.98; 95% CI, 0.88–1.10; p=0.08).

Operation or intervention was more likely following AGB compared to RYGB (p<0.001) but less likely for SG than RYGB (p=.003). The estimated cumulative probability of operation or intervention was higher for AGB, followed by RYGB and then SG. The probability for AGB was 7.0% (6.7–7.3%) at one year, 12.6% (12.1–3.1%) at three years and 18.3% (17.6–19.0%) at five years.

Endoscopic intervention was less likely for SG vs. RYGB (p<0.001) and also less likely for AGB vs. RYGB (p<0.001) (Table 3). The rate of endoscopy was highest for RYGB: 3.7% (3.5–3.8%) at one year, 6.0% (5.7–6.3%) at three years and 8.3% (7.9–8.7%) at five years.

Revisional procedures were most common after AGB, followed by SG and then RYGB (adjusted hazard ratios (AHRs) of AGB vs. RYGB, 11.3; p<0.001; AHR of SG vs. RYGB, 2.9; p<0.001). The highest estimated cumulative probability of revision was on AGB patients: 5.5% (5.2–5.8%) at one year, 9.3% (8.8–9.8%) at three years and 14.9% (14.1–15.7%) at five years (Figure 1).

Figure 1: Probability of revision/conversion by procedure type at five years

Hospitalisation was less likely after ABG and SG than after RYGB: AGB vs. RYGB, p<0.001; SG vs. RYGB, AHR=0.79; 95%CI, 0.76–0.83; p<0.001. The estimated cumulative incidence rates of hospitalisation for RYGB were 14.3% (14.0–14.7%) at one year, 30.0% (29.4–30.6%) at three years and 42.3% (41.5–43.0%) at five years.

For all-cause mortality, the AHR was significantly lower after SG than RYGB (p=0.004). Compared to RYGB, AGB was associated with lower mortality risk (p=0.001). The estimated cumulative risk of all-cause mortality for RYGB was 0.34% (0.30–0.38%) at one year, 0.64% (0.57–0.71%) at three years and 0.98% (0.88–1.09%) at five years.

“Our results extend the PCORnet Bariatric Study results by adding claims data representative of academic and non-academic medical centres, which could provide additional perspectives and guidance, and a better understanding of the range of longer-term outcomes from bariatric procedures,” the authors concluded.

Further information

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