A. D. Jalilvand1, J. Sojka1, K. Shah1, B. J. Needleman1, S. F. Noria1 1Ohio State University,General And Gastrointestinal Surgery,Columbus, OH, USA
Introduction: The surgical weight loss program at our institution requires patients to comply with a liver-shrink diet (LSD) 1-3 weeks prior to bariatric surgery (BS) in order to facilitate liver retraction during surgery. However, the effect of LDS-induced weight-loss on weight-loss after BS is unclear. The primary objective of this study was to examine the correlation between LSD-induced weight-loss and post-operative weight loss outcomes. Secondary objectives included identifying other factors that correlated to improved weight-loss after surgery.
Methods: All patients who underwent primary laparoscopic sleeve gastrectomy (LSG) or Roux-en-Y gastric bypass (LRNYGB) between July 2014 and June 2016 were retrospectively reviewed at a single academic institution. Baseline demographic and operative data was obtained using the electronic medical record. The LSD consisted of a partial-liquid, low carbohydrate, high protein diet that utilized 4 protein shakes and 1 low carbohydrate meal/day. Percent excess body weight-loss (EBWL) was calculated for each patient on LSD (EBWL-LSD), as well as at 2, 8, and 24 weeks after BS. Student’s t-test, Mann-Whitney-U, Chi squared, and Fisher’s Exact were utilized to calculate significance. Multivariate linear regressions were conducted to determine independent predictors of weight-loss. A p-value of <0.05 was considered significant.
Results: During the study period, 588 patients underwent primary BS, of which 57.14% had LSG and 42.86% underwent LRNYGB. Of these, 78.91% (464) were female, and the mean preoperative BMI was 48.8 ± 8.95 kg/m2. The mean time spent on the LSD was 18.21 ± 7.32 days, and median EBWL-LSD was 4.7% (1.73-7.61). Greater EBWL-LSD was observed in patients who were on the LSD for > 2 weeks (5.35% vs 3.09%, p<0.0005), and in men (median of 6.2% vs 4.23%, p=0.0001). Significant independent predictors of EBWL 2 weeks post-operatively included EBWL-LSD (p<0.0005) and male sex (p<0.0005), when adjusting for surgery type, baseline EBW, and age. Patients who achieved at least the median EBWL at 2 weeks (15.4%) had greater EBWL-LSD than those who did not (5.7% vs 4%, p<0.0005). The only significant predictor of EBWL at 2 months was 2-week EBWL (p <0.0005), when adjusting for EBWL-LSD, surgery type, and gender. At 24 weeks, significant independent predictors for EBWL included EBWL at 2 and 8 weeks (p=0.001, p<0.0005), and LRNYGB (p=0.002).
Conclusion: Greater EBWL-LSD is associated with male gender and longer duration on the LSD. EBWL-LSD was a significant independent predictor of EBWL at 2 weeks, while EBWL at 2 and 8 weeks were independent predictors for weight loss at 24 weeks. Patients who reached at least 5.7% EBWL-LSD were in the 50th percentile of EBWL at 2 weeks. This suggests that EBWL-LSD can predict optimal early weight loss outcomes after BS and be used to guide expectations both in preparation for, and after bariatric surgery.