Training programs influence in the learning curve of laparoscopic gastric bypass for morbid obesity: a systematic review.

The makeup of a new surgical bariatric team may be associated with a higher number of postoperative complications due to the learning curve. The aim of this study was to evaluate the outcomes during the learning curve of laparoscopic gastric bypass (LGBP) depending on surgeons' training. A systematic approach was used to review studies from the Pubmed, Embase (Ovid), Cancer Lit, Biomes Central via Scirus, Current Contens (ISI), and Web of Science (SCI) databases. Two reviewers independently screened all titles/abstracts and included/excluded studies based on full copies of manuscripts. The outcomes included were: specific training of the surgeon, postoperative complications (leaks, occlusion, hemorrhage, pneumonia, etc.), mortality, and surgical technique. One reviewer put data onto an Excel spreadsheet. Statistical analysis was performed with weighted linear regression. We identified 448 citations, of which 120 abstract and 50 full-text publications were reviewed. Fourteen papers were selected. Data from 1,848 patients were included. Eighteen different surgeons were analyzed during their learning curve (including the first author of this study). Surgeons were divided into two groups: (1) without formal laparoscopic bariatric training (13 surgeons) and (2) with formal laparoscopic bariatric training (five surgeons). Postoperative complications were more frequent in group 1: 18.1% (± 7.6) vs. 7.7% (± 1.96, p = 0.046); also, mortality was more frequent in group 1: 0.57% (± 0.87) vs. 0% (p = 0.05). An appropriated training in laparoscopic bariatric surgery contributes to a significant reduction in postoperative complications and mortality during the learning curve of LGBP.

Evaluation of bone mineral density loss in morbidly obese women after gastric bypass: 3-year follow-up.

Studies that evaluate the influence of gastric bypass (RYGP) on bone mass are limited to short-term follow-up. We analysed changes in bone mineral density (BMD) three years after surgery and evaluated the main determinants of the development of bone disease. Prospective study of 59 morbidly obese white women aged 46 ± 8 years. BMD scanning using DEXA and plasma determinations of calcium, parathyroid hormone, 25-hydroxyvitamin D and insulin-like growth factor-I were made prior, at 12 months and 3 years after surgery. In the first postoperative year BMD decreased at femoral neck (FN) 10.2 % and in the lumbar spine (LS) 3.2 %, in the third year it additionally decreased 2.7 % and 3.1 %, respectively. BMD at both sites remained above the values of women of the same age. In the follow-up, 1.7 % developed osteoporosis at FN and 6.8 % at LS. Patients with bone disease were older, the percentage of women with menopause was greater in this group and had lower initial and final values of lean mass. The percentage of BMD loss at FN remained positively associated with the percentage of lean mass loss [ß 0.304, p=0.045], and menopause [ß 0.337, p=0.025]. Major osteoporotic fracture and hip fracture risk was low even in menopausal patients (3.1 % and 0.40 %, respectively). After RYGP menopausal women and those with greater lean mass loss are at higher risk of BMD loss but progression to osteoporosis is uncommon and the risk of fracture is low.

[Study of the relationship between adiponectin, interleukin-18, ghrelin and bone mineral density in morbidly obese women after gastric bypass]. / Estudio de la relación entre las concentraciones plasmáticas de adiponectina, interleucina 18 y ghrelina y la densidad mineral ósea en mujeres con obesidad mórbida tras bypass gástrico.

OBJECTIVE: Analysis of the relationship between adiponectin, interleukin-18 (IL-18) and ghrelin and bone mineral density (BMD), in a group of women that had undergone a gastric- bypass for morbid obesity a year before. METHODS: Forty-one morbidly obese patients aged 46 +/- 9 years and with an initial body mass index of 49.5 +/- 7.6 were included in the study and a gastric by-pass operation was performed in all of them. Anthropometric variables, body composition measured with dual energy X-ray absorptiometry (DEXA) and plasma concentrations of parathormone (PTH), 25(OH) vitamin D, insulin growth factor (IGF-I), adiponectin, IL-18 and ghrelin were determined before and a year after surgery. BMD was evaluated with DEXA 12 months after bariatric surgery. RESULTS: A year after surgery 36.2% of inicial body weight was lost and this was associated with an improvement of the inflammatory profile reflected by a significant reduction of IL-18 and a increase of adiponectin plasma concentrations. In the univariate analysis BMD inversely correlated with age (r = -0.287, p = 0.008) and with lean mass (r = 0.318, p = 0.043) but not with adiponectin, IL-18 and ghrelin concentrations. PTH showed a positive correlation with weight (r = 0.362, p = 0.03), lean mass (r = 0.372, p = 0.039), and a negative association with plasma concentrations of calcium (r = -0.48, p = 0.003) and 25(OH) vitamin D (r = -0.44, p = 0.014). Plasma 25(OH) vitamin D correlated negatively with the sum of fat mass and lean mass measured with DEXA (r = -0.210, p = 0.043). In the multiple regression analysis BMD remained associated only with lean mass (beta = 0.193, p = 0.016). CONCLUSIONS: Our study does not support the existance of a direct effect of adipose tissue on bone metabolism through the secretion of adiponectin. The absence of association between inflammatory cytokine IL-18 and ghrelin with BMD also argues against their implication in bone regulation.

Evaluation of bone disease in morbidly obese women after gastric bypass and risk factors implicated in bone loss.

BACKGROUND: In patients undergoing gastric bypass, massive weight loss and impairment of calcium intake and absorption in the duodenum and proximal jejunum may increase the risk of bone mass loss and fractures. However, few data are available regarding the impact of this surgery on the skeleton. The aim of our study was to examine the skeletal changes in a cohort of morbidly obese Caucasian women during the first year after gastric bypass and to analyse the factors implicated in the development of bone loss. METHODS: Sixty-two morbidly obese white women aged 45.3 +/- 8.9 years were studied. Anthropometric measurements, bone mineral density (BMD) screening using dual-energy X- ray absorptiometry and plasma determinations of calcium, phosphorus, parathyroid hormone (PTH), 25-hydroxyvitamin D [25(OH) D(3)] and insulin-like growth factor-I (IGF-I) were made prior to and 12 months after surgery. RESULTS: A year after surgery, BMD significantly decreased at the femoral neck (10.2 +/- 5.7%) and at the lumbar spine (3.2 +/- 4.4%). In the follow-up, 16.1% of women had osteopenia at the femoral neck and 19.3% at the lumbar spine, and 1.6% developed osteoporosis at the lumbar spine. Patients with bone disease were significantly older; the percentage of women with menopause was greater in this group and had lower initial and final values of lean mass. However, no differences in body mass index, weight loss, fat mass, calcium, PTH, 25(OH) D(3) or IGF-I values were found between groups. In the logistic regression analysis, lean mass 12 months after surgery and menopause were found to be the main determinants of osteopenia after adjusting for age with odds ratios of 0.82 and 9.13, respectively. CONCLUSIONS: There is a significant BMD loss at the femoral neck and lumbar spine a year after gastric bypass. Menopausal patients and those with greater lean mass loss are at greater risk and, consequently, should be closely followed up with periodic densitometries.

Adipocyte fatty acid-binding protein as a determinant of insulin sensitivity in morbid-obese women.

The aim of the study was to evaluate human plasma circulating levels of adipocyte fatty acid-binding protein (A-FABP) and its relationship with proinflammatory adipocytokines and insulin resistance in a severely obese cohort, before and 1 year after a surgical gastric bypass. Plasmatic levels of A-FABP were measured in 77 morbid-obese women before and 1 year after bariatric surgery. Anthropometrical parameters and body composition by bioelectrical impedance analysis were determined. Circulating levels of soluble tumor necrosis factor receptor 2 (sTNFR2), Interleukin 18 (IL-18), adiponectin, and high-sensitive C-reactive protein (hsCRP) were also analyzed. Insulin resistance by homeostasis model assessment of insulin resistance (HOMA-IR) index was calculated. After massive weight loss, A-FABP plasmatic levels decreased significantly [7.6 (8.9) vs. 4.3 (5.1); P<0,001] but no association with circulating adipokines or proinflammatory cytokines, both at the beginning and at the end of follow-up, was observed. A decrease in sTNFR2, IL-18, hsCRP, and an increase in adiponectin levels (P<0.001 in all cases) were observed after the gastric bypass. HOMA-IR index improved 1 year after surgery and after multiple regression analysis remained associated with A-FABP after controlling for confounding variables (beta=0.322, P=0.014; R2 for the model 0.281). In morbid-obese women, plasma A-FABP concentrations were dramatically reduced after gastric bypass surgery. After weight loss this protein contributed to HOMA-IR index independently of proinflammatory/antinflammatory cytokine profile. Further studies are warranted to elucidate the role of A-FABP in the pathogenesis of insulin resistance in morbid obesity.

Regulation of bone mineral density in morbidly obese women: a cross-sectional study in two cohorts before and after bypass surgery.

BACKGROUND: The mechanisms by which increased body weight influence bone mass density (BMD) are still unknown. The aim of our study was to analyze the relationship between anthropometric and body composition variables, insulin growth factor-I (IGF-I), adiponectin and soluble tumor necrosis factor-alpha receptors (sTNFR) 1 and 2 with BMD in two cohorts of morbid obese patients, before and after bypass surgery. METHODS: The first cohort included 25 women aged 48+/-7.6 years studied before bypass surgery. The second included 41 women aged 46+/-9.2 years, 12 months after surgery. We studied anthropometric variables obtained from whole body DEXA composition analysis. Serum IGF-I, intact serum parathyroid hormone, 25-hydroxivitamin D3, plasma adiponectin concentrations, sTNFR1, sTNFR2 concentrations were measured. RESULTS: In the first cohort, the BMI was 44.5+/-3.6 kg/m2, parathyroid hormone, IGF-I, and adiponectin concentrations were lower, and sTNFR1 concentrations were higher than in the second cohort. In the multiple regression analysis, BMD remained significantly associated with body fat percentage (beta -0.154, p=0.01), lean mass (beta 0.057, p=0.016) and phosphate concentration (beta 0.225, p=0.05). In the second cohort, BMI was 31+/-5.1 kg/m2. In the multiple regression analysis, BMD remained significantly associated with lean mass (beta 0.006, p=0.03). CONCLUSION: The inverse correlation found between body fat and BMD in the first cohort indicates morbid obesity increases the risk of osteoporosis and we found a positive correlation with lean and fat mass before bariatric surgery and with lean mass after bypass surgery.

Monocyte chemoattractant protein-1 in obesity and type 2 diabetes. Insulin sensitivity study.

OBJECTIVE: Our goal was to test any association between human plasma circulating levels of monocyte chemoattractant protein-1 (cMCP-1) and insulin resistance and to compare monocyte chemoattractant protein-1 (MCP-1) adipose tissue gene expression and cMCP-1 in relation with inflammatory markers. RESEARCH METHODS AND PROCEDURES: cMCP-1 was measured in n = 116 consecutive control male subjects to whom an insulin sensitivity (S(i)) test was performed. Circulating levels of soluble CD14, soluble tumor necrosis factor receptor type 2 (sTNFR2), soluble interleukin-6 (sIL-6), and adiponectin also were measured. Subcutaneous adipose tissue samples were obtained from n = 107 non-diabetic and type 2 diabetic subjects with different degrees of obesity. Real-time polymerase chain reaction was used to measure gene expression of MCP-1, CD68, tumor necrosis factor-alpha (TNF-alpha), and its receptor TNFR2. RESULTS: In the S(i) study, no independent effect of cMCP-1 levels on insulin sensitivity was observed. In the expression study, in non-diabetic subjects, MCP-1 mRNA had a positive correlation with BMI (r = 0.407, p = 0.003), TNF-alpha mRNA (r = 0.419, p = 0.002), and TNFR2 mRNA (r = 0.410, p = 0.003). In these subjects, cMCP-1 was found to correlate with waist-to-hip ratio (r = 0.322, p = 0.048). In patients with type 2 diabetes, MCP-1 mRNA was up-regulated compared with non-diabetic subjects. TNF-alpha mRNA was found to independently contribute to MCP-1 mRNA expression. In this group, CD68 mRNA was found to correlate with BMI (r = 0.455, p = 0.001). DISCUSSION: cMCP-1 is not associated with insulin sensitivity in apparently healthy men. TNF-alpha is the inflammatory cytokine associated with MCP-1 expression in subcutaneous adipose tissue.