Long-term body composition improvement in post-menopausal women following bariatric surgery: a cross-sectional and case-control study
Objective: Bariatric surgery (BS) induces loss of body fat mass (FM) with an inexorable loss of lean mass (LM). Menopause leads to deleterious changes in body composition (BC) related to estrogen deficiency including LM loss and increase in total and visceral adipose tissue (VAT). This study aims to describe long-term weight evolution of post-menopausal women after RYGB (Roux-en-Y gastric bypass) and to compare BC between BS patients versus post-menopausal non-operated women. Design: Cross-sectional study of 60 post-menopausal women who underwent RYGB ≥ two years prior to the study with nested case-control design. Methods: Post-menopausal BS women were matched for age and BMI with controls. Both groups had DXA scan, lipids and glucose metabolism markers assessment. Results: Median follow-up was 7.5(2–18) years. Percentage of total weight loss (TWL%) was 28.5±10%. After RYGB, LM percentage of body weight (LM%) was positively associated with TWL% and negatively associated with nadir weight. Forty-one post-BS women were matched with age- and BMI-controls. Post-BS patients showed higher LM% (57.7%[±8%] versus 52.5%[±5%], p=0.001), reduced FM% (39.4%[±8.4%] versus 45.9%[±5.4%] p<0.01) and lower VAT (750.6g[±496] versus 1295.3g[±688], p<0.01) with no difference in absolute LM compared to controls. While post-BS women showed a better lipid profile compared to controls, no difference was found in glucose markers. Conclusions: Post-menopausal women after RYGB have a lower FM and VAT, preserved LM and a better lipid profile compared to controls. Weight loss after RYGB seems to have a persistent positive impact on metabolic health.