METABOLIC CHANGES AFTER SURGICAL SUBCUTANEOUS FAT REMOVAL

Abstract

Background: There is increasing demand for both surgical (SSFR) and nonsurgical (NSSFR) subcutaneous fat removal procedures for achieving immediate improvements in physical appearance. However, their metabolic effects remain unclear. Aims: Firstly, to review the current state of knowledge on the metabolic changes after SSFR and identify any literature gaps. Secondly, to examine the magnitude and sustainability of these changes and explore the impact of prior obesity surgery on changes in glucose homeostasis after SSFR. Methods: An umbrella review was conducted to identify knowledge gaps, and implications for future research. Then, twin dose response meta-analyses (DRMA) were performed to examine the degree and duration of these metabolic changes after SSFR & NSSFR procedures. This was followed by a commentary paper that highlights the need to examine additional sources of population heterogeneity, which could alter the metabolic trajectory after SSFR. Next, a novel index of glucose excursion was validated which was then used subsequently in a quasi-experimental pilot study to examine changes in glucose homeostasis after SSFR in comparison to the impact of prior obesity surgery. Results: The umbrella review revealed that current literature is not conclusive; however, they suggest some metabolic benefits without a clear clinical significance. The DRMAs reported that SSFR is safe and may exert a transient metabolic benefit in body composition, adipokines, inflammation, blood pressure and lipid profile. However, only improvements in insulin sensitivity lasted beyond 6 months. On the other hand, NSSFR exerts a sustained effect on body composition for up to two months, but with a worsening in lipid profile in the first two weeks. The commentary paper highlighted the need to examine the independent metabolic effect of SSFR and history of bariatric surgery (irrespective of their body mass index and diabetic status). The quasi experiment validated Doi's weighted average glucose as a measure of post-load glucose excursion. Also reported that SSFR resulted in improvement in insulin resistance without affecting post-load glucose excursion, but that a history of obesity surgery was associated with an additional effect on glucose excursion, possibly due to sustained improvement of beta-cell function. Conclusion: SSFR appears to be associated with favorable metabolic changes, particularly an improvement in insulin sensitivity. Further studies that examine these changes from a hormonal perspective can broaden our knowledge of metabolic sequelae associated with sudden removal of subcutaneous fat and help us understand mechanisms underpinning the link between obesity and metabolic diseases. This could potentially identify new therapeutic targets.