Cephalic Phase in Anorexia Nervosa,Bulimia Nervosa and Obese Binge Eaters (Cephalic 1)

July 4, 2007 updated by: Tel-Aviv Sourasky Medical Center

The objective of this trial is to examine the cephalic phase insulin response (CPIR) and pancreatic polypeptide (PP) release as indicators of the cephalic phase occurrence and magnitude to palatable food stimulus in anorectic and bulimic subgroups as compared to healthy controls

Study Overview

Status

Unknown

Conditions

Intervention / Treatment

Procedure: chocolate cake

Detailed Description

Food stimulation of gastric and pancreatic secretion is classically divided into cephalic, gastric and intestinal phases.

Cephalic phase refers to a simultaneous activation of gastrointestinal motility, gastric acid and pancreatic enzyme secretion ,as well as, release of hormones from the endocrine pancreas which occurs through activation of vagal -efferents as a result of food-related sensory stimuli such as taste and smell prior to nutrient absorption and which coincides with a thermogenic response.

Of the cephalic phase secretions, cephalic phase insulin release (CPIR) has received the most attention, but pancreatic polypeptide (PP) and glucagon responses have also been studied. While the magnitude of cephalic phase insulin release is relatively small (25% above baseline), pancreatic polypeptide increases 100% above baseline. The large magnitude of the PP response makes it a sensitive indicator of vagal activation to food stimuli.

In most experiments, subjects are either exposed to visual and olfactory stimulation by seeing and smelling the food stimulus or are required to perform a modified sham-feed, i.e. to taste, chew and then expectorate the food stimulus.

In general, cephalic phase are thought to be preparatory response before ingestion of food. Because of their small magnitude, the physiological significance of the cephalic phase hormonal responses has been largely discounted. However, there is evidence that experimental prevention of CPIR lead to hyperinsulinemia and hyperglycemia. Therefore, CPIR may contribute to glucose homeostasis /regulation. Moreover CPIR may be an indicator of hunger and could be important for understanding eating disorders.

In parallel with these hormonal secretion ,an increase in energy expenditure has also been observed . This thermogenic response to food is even greater with sham feeding than with normal feeding and is paralleled by changes in RQ showing enhanced carbohydrate oxidation.

Studies conducted in obese humans demonstrate exaggerated absolute magnitude of CPIR .However basal hyper-insulinemia which is typically observed in obese individuals may clouds this observation. Moreover, it has been hypothesized that CPIR is attenuated in obese when is expressed as a percentage of baseline and therefore they may not secrete enough insulin during pre-absorptive period to regulate postprandial glucose levels.

There is also evidence that obese people with insulin resistance have a reduced thermogenic response to feeding .

Only limited numbers of studies have been done on the cephalic phase in anorexia and bulimia. There are findings of a significant CPIR in anorexics as compared to controls which tends to rule out a deficient cephalic insulin response as a contributor to the self-starvation observed in anorexia nervosa. As to bulimics who often show endocrine abnormalities, their CPIR was only slightly differ or from controls.

These findings suggest more complex determinants of eating disorders than physiological state alone.

Study Type

Interventional

Enrollment (Anticipated)

Phase

Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

Israel
- - Tel Aviv, Israel, 64239
    - Recruiting
    - TASMC
    - Contact:
      
      Nachum Vaisman, Prof.
      
      Phone Number: +972-524-266596
      
      Email: vaisman@tasmc.health.gov.il

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

14 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Genders Eligible for Study

All

Description

Inclusion Criteria:

75 patients will be divided into the following 4 subgroups;

. 15 patients with anorexia nervosa.
. 15 patients with bulimia nervosa (purging type).
. 15 patients with binge eating disorder and obesity.
. 15 obese patients without eating disorder
. 15 Non-eating disordered normal weight patients.

Non diabetic and non-pregnant patients above 18 years of age without gastrointestinal diseases and without medications which can affect gastrointestinal motility and appetite.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Interventional Model: Parallel Assignment
Masking: None (Open Label)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
VAS, EDI, Blood test for glucose, insulin, PP, shame feed procedure Time Frame: 1 year	1 year

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Tel-Aviv Sourasky Medical Center

Investigators

Principal Investigator: Nachum Vaisman, Prof., TASMC Israel

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

July 1, 2007

Study Completion (Anticipated)

December 1, 2007

Study Registration Dates

First Submitted

June 27, 2007

First Submitted That Met QC Criteria