A Higher Phase Angle Is Associated with Greater Metabolic Equivalents in Women 1 Year After Bariatric Surgery.

BACKGROUND: Phase angle (PhA), proposed as an indicator of the number, integrity, and function of cells and evaluated in some clinical situations, decreases after bariatric surgery (BS). In contrast, higher values are found in physically active or exercising individuals. We therefore evaluated the influence of physical activity on PhA after BS. METHODS: The PhA and body composition (obtained by bioelectrical impedance analysis), physical activity level (obtained by International Physical Activity Questionnaire), and metabolic equivalents (METs) were evaluated in adult women submitted to BS. The PhA and body composition were evaluated at three time points: before and 6 and 12 months after surgery. Physical activity level and METs were measured at the two postoperative time points. RESULTS: A reduction in PhA was observed 6 (p < 0.01) and 12 months (p < 0.01) after BS, with no significant difference between time points. A moderate or high physical activity level was found in 81% of the volunteers after 6 months and in 65% after 12 months. METs were reduced after 12 months compared to 6 months. A positive correlation (p < 0.05) was observed between PhA and body cell mass after surgery. There was a significant positive correlation (p < 0.01) between PhA and METs after 12 months. CONCLUSIONS: Physical activity may attenuate the PhA reduction that occurs after BS, with this parameter reflecting the engagement of these patients in this type of activity.

Roux-en-Y Gastric Bypass and Sleeve Gastrectomy Differently Affect Oxidative Damage Markers and their Correlations with Body Parameters.

BACKGROUND: Bariatric surgery improves oxidative damage, but little is known about the differences between Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). This study compared changes in lipid and protein oxidative damage markers and their correlations with body parameters of patients before and after RYGB or SG. METHODS: Body mass index (BMI), bioimpedance parameters, and biochemical parameters including lipid and protein oxidative damage markers were evaluated before and 6 months after surgery. Data were analyzed by t test or Mann-Whitney rank sum test and Spearman's correlation coefficient between oxidative damage and other parameters. RESULTS: Twenty-five patients were submitted to RYGB and 14 to SG. There was a significant decrease of BMI, fat mass, fat-free mass, phase angle, serum total protein, transthyretin, and C-reactive protein in both groups (p < 0.05). Serum thiobarbituric acid reactive substances (TBARS), advanced oxidation protein products (AOPP), and serum lipids (p < 0.05) were significantly decreased in the RYGB group. TBARS levels were significantly correlated with serum total cholesterol (r = 0.468), LDL (r = 0.439), BMI (r = 0.424), and fat mass (r = 0.40) (p < 0.05). In the SG group, AOPP levels were significantly correlated with serum C-reactive protein (baseline: r = 0.53, 6 months: r = 0.64) (p < 0.05). Alterations in these levels were negatively correlated with changes in BIA parameters [resistance (r = -0.574), reactance (r = -0.736), and phase angle (r = 0.549)] (p < 0.05). CONCLUSIONS: RYGB seems to be better in attenuating oxidative damage after 6 months. The BMI reduction in the RYGB group suggests a concomitant decrease of lipid oxidative damage. In the SG group, changes in BIA parameters were inversely correlated with protein oxidative damage.