Ontario bariatric outcomes comparable to major centres

Ontario bariatric outcomes

The overall complication rate was 11.7% (95% confidence interval [CI] 10.8%-1%, 2.6), with 11.9% occurring in the bypass group and 9.9% in the sleeve gastrectomy group (p=0.2).

An analysis of short-term outcomes of bariatric surgery in Ontario appear to be comparable to those of other major centres and improving over time, although further studies are needed to examine the reasons why there are variations in outcomes between centres of excellence. The analysis was published by researchers from St Joseph’s Healthcare and McMaster University, Hamilton, Ontario.

The paper, ‘Outcomes of the Ontario Bariatric Network: a cohort study’, published in CMAJ Open (a journal of the Canadian Medical Association) examined the short-term outcomes from Canada’s largest bariatric collaborative, from Ontario, during its first three years (March 2009 to April 2012).

They researchers performed a population-based cohort study that included all patients who received a roux-en-y gastric bypass or sleeve gastrectomy. The primary outcomes included short-term overall complication rate, reoperation rate, anastomotic leak rate and death. A median odds ratio (OR) was used to compare risk-adjusted complication rates across centres of excellence.

Outcomes

A total of 5,007 procedures (91.7% roux-en-y gastric bypass, 8.3% sleeve gastrectomy) were performed during the three-year study period. The mean age of patients was 44.6 years (±10.3) and 81.9% of patients were female. At baseline, comorbidities included: obstructive sleep apnoea, diabetes, hypertension and gastro-oesophageal reflux affected 30.9%, 29.6%, 27.2% and 6.6% of patients, respectively.

Gastric bypass patients tended to be younger (44.4 vs. 47.0 yr; p<0.001), were less likely to be male (17.8% vs. 21.6%; p=0.05) and had fewer comorbidities, with lower rates of obstructive sleep apnoea, chronic kidney disease, hypertension, coronary artery disease and chronic obstructive pulmonary disease (p<0.05).

The overall complication rate was 11.7% (95% confidence interval [CI] 10.8%-1%, 2.6), with 11.9% occurring in the bypass group and 9.9% in the sleeve gastrectomy group (p=0.2). There were a total of eight deaths during the study (0.16% (95% CI 0.07%-0.31%), which was not statistically different in either group (0.15% in the bypass group v. 0.24% in the sleeve gastrectomy group, p=0.5). The re-operation rate was 4.6% (95% CI 4.0%-5.2%) and was lower in the sleeve gastrectomy group (3.1% v. 4.8%), but the different was not significant (p=0.1). The leak rate in the study population was 0.84% (95% CI 0.61%-1.13%) and was similar in the two groups (0.83% in the bypass group v. 0.96% in the sleeve gastrectomy group, p=0.8).

Female sex appeared to be protective against complications (OR 0.74, 95% CI 0.59-0.91; p=0.006) fro surgery, as was the presence of osteoarthritis (OR 0.32, 95% CI 0.13- 0.80; p=0.01), whereas the presence of chronic kidney disease was associated with a nearly fivefold increase in complications (OR 4.96, 95% CI 2.52-9.75; p<0.001). Notably, age, type of procedure (i.e., bypass v. sleeve gastrectomy), diabetes mellitus, hyperlipidemia, obstructive sleep apnoea, hypertension, coronary artery disease, chronic obstructive pulmonary disease and gastro-oesophageal reflux did not confer an increased risk (p>0.05), as shown in Table 1.

Table 1: Predictors of short-term complications after bariatric surgery – CI = confidence interval, COPD = chronic obstructive pulmonary disease, GERD = gastro-oesophageal reflux disease, OR = odds ratio (Credit: CMAJ Open)

“Further studies are needed to provide data on the health outcomes in the long term, such as percent excess weight loss, remission or improvement of medical co-morbidity,” the authors conclude. “In addition, further studies exploring reasons behind variations in outcomes between centres of excellence are needed to help bridge the gap and to ensure patients continue to have access to exceptional care.”