Jejunal administration of glucose enhances acyl ghrelin suppression in obese humans.

Ghrelin is a gastric hormone that stimulates hunger and worsens glucose metabolism. Circulating ghrelin is decreased after Roux-en-Y gastric bypass (RYGB) surgery; however, the mechanism(s) underlying this change is unknown. We tested the hypothesis that jejunal nutrient exposure plays a significant role in ghrelin suppression after RYGB. Feeding tubes were placed in the stomach or jejunum in 13 obese subjects to simulate pre-RYGB or post-RYGB glucose exposure to the gastrointestinal (GI) tract, respectively, without the confounding effects of caloric restriction, weight loss, and surgical stress. On separate study days, the plasma glucose curves obtained with either gastric or jejunal administration of glucose were replicated with intravenous (iv) infusions of glucose. These "isoglycemic clamps" enabled us to determine the contribution of the GI tract and postabsorptive plasma glucose to acyl ghrelin suppression. Plasma acyl ghrelin levels were suppressed to a greater degree with jejunal glucose administration compared with gastric glucose administration (P < 0.05). Jejunal administration of glucose also resulted in a greater suppression of acyl ghrelin than the corresponding isoglycemic glucose infusion (P ≤ 0.01). However, gastric and isoglycemic iv glucose infusions resulted in similar degrees of acyl ghrelin suppression (P > 0.05). Direct exposure of the proximal jejunum to glucose increases acyl ghrelin suppression independent of circulating glucose levels. The enhanced suppression of acyl ghrelin after RYGB may be due to a nutrient-initiated signal in the jejunum that regulates ghrelin secretion.

Lipoprotein Profiles in Class III Obese Caucasian and African American Women with Nonalcoholic Fatty Liver Disease.

Triglyceride content in the liver is regulated by the uptake, production and elimination of lipoproteins, and derangements in these processes contribute to nonalcoholic fatty liver disease (NAFLD). Previous studies show a direct relationship between intrahepatic fat and production of apolipoprotein B100 (apoB100) containing particles, VLDL and LDL, but little consensus exists regarding changes in lipoprotein production in the development of simple steatosis (SS) versus nonalcoholic steatohepatitis (NASH). Further, ethnic variations in lipoproteins among SS and NASH are unknown as is how such variations might contribute to the differential prevalence of disease among Caucasians versus African Americans. In this study, we assessed plasma lipoprotein profiles by nuclear magnetic resonance (NMR) spectroscopy in 70 non-diabetic class III obese females recruited from the surgical weight loss clinic. Of these, 51 females were stratified by biopsy-staged NAFLD severity (histologically normal, SS, or NASH). NASH females displayed increased circulating triglycerides and increased VLDL particle number and size relative to those with histologically normal livers, while total and large LDL concentration decreased in SS versus NASH and correlated with increased insulin resistance (via HOMA2-IR). When Caucasian women were examined alone (n = 41), VLDL and triglycerides increased between normal and SS, while total LDL and apoB100 decreased between SS and NASH along with increased insulin resistance. Compared to Caucasians with SS, African American women with SS displayed reduced triglycerides, VLDL, and small LDL and a more favorable small to large HDL ratio despite having increased BMI and HOMA2-IR. These findings suggest that ApoB100 and lipoprotein subclass particle number and size can delineate steatosis from NASH in obese Caucasian females, but should be interpreted with caution in other ethnicities as African Americans with SS display relatively improved lipoprotein profiles. This may reflect variation in the relationship between dyslipidemia and NAFLD progression across gender and ethnicity.

Patient variables which may predict length of stay and hospital costs in elderly patients with hip fracture.

OBJECTIVES: To investigate what factors contribute to increased length of stay (LOS) and increased costs in treatment of elderly patients with hip fractures. DESIGN: Retrospective chart review. SETTING: All patients who presented to a large tertiary care center between January 2000 and December 31, 2009. PARTICIPANTS: Charts for all patients older than 60 years who presented with isolated low-energy hip fractures were reviewed. Of the 719 patients identified, 660 were included. INTERVENTION: Patients who underwent operative fixation or hemiarthroplasty secondary to hip fracture were identified using a search of Current Procedural Terminology (CPT) codes search. MAIN OUTCOME MEASUREMENTS: Gender, height, weight, body mass index, length of procedure, American Society of Anesthesiologists (ASA) classification, and medical comorbidities were gathered and compared with LOS and direct daily inpatient hospital cost. RESULTS: No correlation existed between body mass index or specific comorbidities and LOS, but ASA classification was a predictor. For each ASA increase of 1, average LOS increased 2.053 days (P < 0.001). Given total daily cost to the hospital for these patients was $4530, each increase in ASA classification translated to an increase of $9300. CONCLUSIONS: ASA classification proved useful in estimating LOS and cost for patients undergoing operative fixation of hip fractures. Because ASA classification and cost are universally collected, this method can be employed in almost any hospital. This highlights a role for ASA classification in preoperative estimation of the elderly patient's cost and a potential advantage for incorporating patient factors in the development of tiered reimbursement models. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.