Introduction Patients considered for laparoscopic adjustable gastric banding (LAGB) are encouraged to lose weight pre-operatively, based on the hypothesis that good pre-operative dietary weight loss correlates with a favourable post-operative outcome and allows safe surgery. This study aims to assess whether pre-operative weight loss is a true predictor of post-operative weight loss in patients who underwent LAGB for morbid obesity.

Methods A retrospective analysis of patients who underwent LAGB in 2007 at our institution by a single surgeon, using actual body weight loss pre-operatively (from patient's BMI at the bariatric surgical clinic vs their BMI on the pre-operative day) and then comparing this to their BMI at 1 and 2 years post-operatively.

Results 69 patients were included in the study (M=23, F=46, M:F=1:2), with a mean age of 45.7 years (Range 19–64). The average BMI at the bariatric surgical clinic was 54.01 (Range = 38–72). The average BMI on the pre-operative day was 52.13 (Range 33–70), which reflected in a mean reduction in BMI of 1.88 (or 4.86 kg) (Range −5–19) or a mean excess percent BMI loss (EBL) of 7.4 kg/m². An analysis of their 1- and 2-year post-operative weight loss compared to their weights from clinic was then performed. At 1 year post-operatively, the mean reduction in BMI was 11.1 (Range = −5–27) or an EBL of 33.6 kg/m². At 2 years post-operatively, the mean reduction in BMI was 13.29 (Range = −1–35) or an EBL of 41.5 kg/m². Correlation between pre-operative weight loss vs weight lost at 1 and 2 years post LAGB was performed using the Spearman Rank Correlation, as the data were not normally distributed. At 1 year post-operatively, the Spearman Rank Correlation was 0.154 (95% CI −0.094 to 0.383) with a p value of 0.208 (no statistical significant correlation). At 2 years post-operatively, the Spearman Rank Correlation was 0.069 (95% CI −0.177 to 0.307) with a p value of 0.573 (no statistical significant correlation). Scatter plot graphs of individual pre-operative weight loss data vs year 1 and year 2 weight loss data confirmed there was no linear correlation.

Conclusion Pre-operative dietary weight loss does not correlate with better outcomes following laparoscopic adjustable gastric banding.

Competing interests None declared.