Methodological Insights and Future Directions in Gut Hormone Studies after Bariatric Metabolic Surgery: A Scoping Review

Abstract

Abstract This scoping review evaluated three systematic reviews (SRs) (SR17, SR21, and SR23) on gut hormones after bariatric metabolic surgery (BMS) to pinpoint areas for methodological enhancement and further exploration. The combined assessment of 170 included studies showed a pooled prevalence of hormones and biomarkers as outcome parameters following BMS. The results indicate varying utilization rates of specific parameters across studies. Ghrelin was absent or not tested in 57.9%–90.9% of the studies, leptin in 25.3%–90.9%, peptide YY in 66.1%–85.3%, glucagon-like peptide-1 in 64.2%–82.1%, glucagon in 96.2%–97.9%, and lipids were absent or not tested in 31.8%–100% of the studies. None of the studies tested patients after weight regain or in revisional surgery on the effect on the gut hormones. In the studies, the average median number per patient varied from 7 to 19 in SR17 and SR21 and 30 to 73 in SR23, with a notable heterogeneity ranging from 53% to 91% for Tau2. Postprandial testing was not performed in SR21 and SR23. Future studies could use predefined clinical research forms and datasets to formulate detailed research. This can determine which gut hormones are crucial for research while also aiming to enhance power quality and reduce heterogeneity. Furthermore, expanding new SR with a focus on associated medical problems, revision surgery, weight regain, fasting and postprandial testing, and the role of the changes of each hormone after BMS on energy and glucose homeostasis could help the BMS field.