Abstract
BACKGROUND: LVSG seems to increase the risk of GERD despite significant weight loss. We compared pre- and postoperative esophageal function test data (in conjunction with the BMI loss) to evaluate the impact of post-LVSG on lower esophageal sphincter pressure (LESP), lower esophageal sphincter length (LESL), and DeMeester Score (DMS). METHODS: Articles analyzing esophageal manometry ±24 h pH-study pre- and post-LVSG were identified using electronic databases from 1999 to 2023. The Critical Appraisal Skills Programme Checklist for Cohort Studies was used for quality assessment. The DerSimonian and Laird random effects model was used for continuous data analysis. Heterogeneity was assessed using the Cochrane Q statistic and I(2) index. Leave one out sensitivity analysis was undertaken to assess the robustness and validity of our analysis. Egger's test was used to evaluate potential publication bias in our meta-analysis. RESULTS: Nineteen studies totaling 668 patients were evaluated (F = 445, M = 131). A significant reduction of 3.82 mm Hg in LESP was observed after LVSG based on 16 studies (WMD 3.82, 95% CI 1.74, 5.90; p < 0.001, I(2) = 88.6%). LESL did not reveal any significant difference between pre- and post-LVSG based on nine studies (WMD 0.05, 95% CI -0.15, 0.26; p = 0.625, I(2) = 83.1%). DMS showed a significant increase of 11.72 post LVSG based on 12 studies (WMD -11.72, 95% CI -17.15 to -6.30; p < 0.001, I(2) = 91.5%). Significant BMI loss of 13.26 kg/m(2) was observed post LVSG based on 12 studies (WMD 13.26, 95% CI 11.65 to 14.88, Z = 16.07, p < 0.001). CONCLUSIONS: LVSG is associated with a significant decrease in LESP and a significant increase in the DMS post-LVSG, leading to the worsening or development of new GERD symptoms despite significant BMI reduction. The limitations of our meta-analysis include small sample sizes, short follow-up, heterogeneity, lack of data on some confounders and inadequate quality of some studies.