MBS might be associated with improved survival in individuals aged 69 years and older with obesity

A matched analysis from Uk researchers has provided preliminary evidence that metabolic and bariatric surgery (MBS) might be associated with improved survival in individuals aged 69 years and older with obesity, and can be performed with acceptable short-term risk in a specialist setting.

The aim of the study was to assess the effect of MBS on long-term survival in patients with obesity aged 69 years and older compared with those of a similar age with obesity who did not undergo MBS. The researchers performed a retrospective cohort study of all patients aged 69 years and older managed in the Imperial Weight Centre (Imperial College Healthcare NHS Trust, London, UK), a high-volume tertiary bariatric surgery unit, between January 2015 and December 2024.

Patients were eligible for inclusion if they were aged 69 years and older and had complete clinical data. Patients managed in the Imperial Weight Centre outside this time period, younger than 69 years, or with incomplete clinical records were excluded. Patients were classified into two groups: those who underwent MBS and those who were assessed for MBS, but did not proceed to surgery.

Surgical procedures included laparoscopic Roux-en-Y gastric bypass (RYGB) and laparoscopic sleeve gastrectomy, which were performed in a single centre by five bariatric surgeons using standardised techniques. Surgical complications were categorised according to the Dindo-Clavien classification.

The primary outcome was all-cause mortality after matching (assessed via univariate and multivariate analyses) and a complete case analysis was applied. Secondary outcomes were mortality in the unmatched cohort, post-operative outcomes, and safety outcomes.

In total, 186 patients were included, with 44 patients (24%) who had MBS and 142 patients (76%) who did not have MBS. The median age was 71 years, 114 (61%) of 186 patients were women, 72 (39%) were men, median BMI was 41kg/m2 and median follow-up duration was 39 months in the full cohort, with similar durations between surgical and non-surgical groups. Before matching, substantial imbalance was observed in median age (SBD 39.2%), cardiovascular disease (SBD 44.7%), and hypertension (SBD 25.6%). Moderate imbalances were present in gender (SBD 18.7%), BMI (SBD 10.3%), ASA physical status grade (SBD 16.3%), dyslipidaemia (SBD 15.0%), and deep vein thrombosis (SBD 15.5%). Type 2 diabetes was well balanced between groups (SBD 3.9%).

In total,122 (86%) of the 142 patients who did not undergo MBS declined surgery themselves and 20 (14%) of 142 patients were deemed too high risk for surgery following multidisciplinary evaluation. Ten (8%) of the 122 patients who declined surgery were older than 75 years compared with ten (50%) of the 20 who were deemed too high risk for surgery (p<0.0001).

In the unmatched cohort, Kaplan–Meier analysis showed no statistically significant difference in survival between the MBS and non-MBS groups (log-rank p=0.081). In the univariate Cox regression model, MBS was associated with a non-significant reduction in all-cause mortality (p=0.16). In the multivariate Cox model, the association remained non-significant (p=0.11).

Following matching (44 patients undergoing MBS vs 34 patients not undergoing MBS), a significant survival benefit was evident. Kaplan–Meier analysis showed superior survival among MBS patients (log-rank p=0.010). MBS was associated with a 68% reduction in all-cause mortality in univariate analysis (p=0.036) and a 75% reduction in all-cause mortality in multivariate analysis (p=0.015), confirming the independent beneficial effect of surgery on survival in the matched cohorts.

Among 44 patients who underwent MBS, 28 (64%) underwent an RYGB and 16 (36%) underwent a laparoscopic sleeve gastrectomy. The median length of stay was two days (IQR 2–3) and one person (2%) required admission to the intensive care unit. The overall 30-day morbidity rate was 9% (four of 44 patients), with one case of pneumonia classified as a Dindo-Clavien grade I–II complication. 30-day major complications (Dindo-Clavien grade III–IV) occurred in three patients (7%), including one case of postoperative bleeding and two cases of port site hernia requiring intervention.

One person (2%) died on postoperative day five due to aspiration pneumonia, and the 30-day readmission rate was 7% (three of 44 patients) due to dehydration (two [5%] of 44) and pneumonia (one [2%] of 44). Among 44 patients who underwent MBS, the mean percentage of total weight loss at last follow-up was 22.0% (SD 12.5). Mean percentage of total weight loss was 25.4% (14.4) in the RYGB group and 20% (11.2) in the laparoscopic sleeve gastrectomy group. The difference in percentage of total weight loss between RYGB and laparoscopic sleeve gastrectomy was not statistically significant (p=0.17).

In the MBS group, the median time from first clinic assessment to surgery was 13.5 months (IQR 9.5–16.5). No deaths occurred during this presurgical interval. In the matched control group, 11 patients died during follow-up, with a minimum time to death of 12 months (median 35 months).

“These findings support further evaluation of MBS in older adults and suggest that age alone should not automatically exclude patients from consideration for MBS,” the researchers concluded. “Prospective studies with larger cohorts are needed to confirm these results and define optimal selection criteria in this population.”

This study was funded by the National Institute for Health and Care Research.

The findings were reported in the paper, 'Metabolic and bariatric surgery in adults aged 69 years and older in England: a matched survival retrospective cohort study', published in The Lancet. To access this paper, please click here