Changes in gastrointestinal hormone responses, insulin sensitivity, and beta-cell function within 2 weeks after gastric bypass in non-diabetic subjects.

BACKGROUND: Roux-en-Y gastric bypass (RYGB) surgery causes profound changes in secretion of gastrointestinal hormones and glucose metabolism. We present a detailed analysis of the early hormone changes after RYGB in response to three different oral test meals designed to provide this information without causing side effects (such as dumping). METHODS: We examined eight obese non-diabetic patients before and within 2 weeks after RYGB. On separate days, oral glucose tolerance tests (25 or 50 g glucose dissolved in 200 mL of water) and a liquid mixed meal test (200 mL 300 kcal) were performed. We measured fasting and postprandial glucose, insulin, C-peptide, glucagon, total and intact glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-2 (GLP-2), peptide YY(3-36) (PYY), cholecystokinin (CCK), total and active ghrelin, gastrin, somatostatin, pancreatic polypeptide (PP), amylin, leptin, free fatty acids (FFA), and registered postprandial dumping. Insulin sensitivity was measured by homeostasis model assessment of insulin resistance. RESULTS: Fasting glucose, insulin, ghrelin, and PYY were significantly decreased and FFA was elevated postoperatively. Insulin sensitivity increased after surgery. The postprandial response increased for C-peptide, GLP-1, GLP-2, PYY, CCK, and glucagon (in response to the mixed meal) and decreased for total and active ghrelin, leptin, and gastrin, but were unchanged for GIP, amylin, PP, and somatostatin after surgery. Dumping symptoms did not differ before and after the operation or between the tests. CONCLUSIONS: Within 2 weeks after RYGB, we found an increase in insulin secretion and insulin sensitivity. Responses of appetite-regulating intestinal hormones changed dramatically, all in the direction of reducing hunger.

The psychosocial quality of work determines whether employment has benefits for mental health: results from a longitudinal national household panel survey.

OBJECTIVES: Although employment is associated with health benefits over unemployment, the psychosocial characteristics of work also influence health. We used longitudinal data to investigate whether the benefits of having a job depend on its psychosocial quality (levels of control, demands and complexity, job insecurity, and unfair pay), and whether poor quality jobs are associated with better mental health than unemployment. METHOD: Analysis of seven waves of data from 7,155 respondents of working age (44,019 observations) from a national household panel survey. Longitudinal regression models evaluated the concurrent and prospective association between employment circumstances (unemployment and employment in jobs varying in psychosocial job quality) and mental health, assessed by the MHI-5. RESULTS: Overall, unemployed respondents had poorer mental health than those who were employed. However the mental health of those who were unemployed was comparable or superior to those in jobs of the poorest psychosocial quality. This pattern was evident in prospective models: those in the poorest quality jobs showed greater decline in mental health than those who were unemployed (B = 3.03, p<0.05). The health benefits of becoming employed were dependent on the quality of the job. Moving from unemployment into a high quality job led to improved mental health (mean change score of +3.3), however the transition from unemployment to a poor quality job was more detrimental to mental health than remaining unemployed (-5.6 vs -1.0). CONCLUSIONS: Work of poor psychosocial quality does not bestow the same mental health benefits as employment in jobs with high psychosocial quality.