Experimental Studies of the Effects of Caffeine on Glucose Regulation

Caffeine and Glucose Regulation

This project contains experimental studies of the effects of the drug caffeine on glucose regulation in adults who have Type 2 diabetes. In our experiments, we are testing the hypothesis that moderate amounts of caffeine exaggerate the abnormal increases in glucose and insulin observed after meals in patients with type 2 diabetes. On separate study days subjects receive standard meals after taking capsules containing either caffeine or an inactive placebo. We measure levels of glucose, insulin, and other chemicals in blood samples drawn over the next 3 hours. In a separate study, we use continuous glucose monitoring to measure glucose levels during everyday activities on days when subjects receive caffeine or placebo.

These studies do not involve clinical treatment or disease management. However, we hope to learn whether a very popular drug impairs the clinical management of a common disease.

Study Overview

Status

Completed

Intervention / Treatment

Detailed Description

Pilot results suggest that caffeine, the most commonly used drug in the world, may interfere with postprandial glucose metabolism by increasing insulin resistance and/or by stimulating hepatic glucose production. This effect could have serious clinical implications for coffee drinkers who have type 2 diabetes. Early results suggest caffeine exaggerates the postprandial hyperglycemia and hyperinsulinemia present in these patients.

The experimental (non-treatment) studies in this project include double-blind placebo-controlled cross-over laboratory tests of glucose tolerance in groups of type 2 diabetic patients and prediabetic volunteers who are coffee drinkers.

The lab studies test the hypothesis that caffeine (vs. placebo) increases postprandial insulin responses and results in a potentiation of glucose responses in the type 2 group.

An ambulatory study examines the effects of caffeine administration on glucose levels during everyday activities in the natural environment. This study uses a double-blind placebo-controlled cross-over design. Ambulatory glucose data are collected with a MiniMed CGMS sensor and recorder worn for 72 hours. Caffeine and placebo are administered on separate days. Average glucose levels and glucose responses to meals are compared across treatment days within subjects.

Study Type

Interventional

Enrollment

150

Phase

  • Early Phase 1

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

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion criteria:

  • 6 months or longer history of type 2 diabetes
  • treatment by diet, exercise, or oral medication
  • current daily consumption of 2 or more cups of coffee
  • BMI >21kg/M2 and < 45kg/M2

Exclusion criteria:

  • Required use of insulin
  • Current cigarette smoking
  • Current use of medications that impact glucose metabolism
  • Pregnancy
  • Other major medical disorders

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: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Double

What is the study measuring?

Primary Outcome Measures

Outcome Measure
glucose tolerance
insulin resistance
postprandial glucose and insulin
fasting glucose and insulin

Secondary Outcome Measures

Outcome Measure
blood pressure
cortisol
epinephrine
norepinephrine
plasma caffeine concentration

Collaborators and Investigators

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

Investigators

  • Principal Investigator: James D. Lane, Ph.D., Duke University

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, 2004

Study Completion

February 1, 2007

Study Registration Dates

First Submitted

February 5, 2007

First Submitted That Met QC Criteria

February 7, 2007

First Posted (Estimate)

February 8, 2007

Study Record Updates

Last Update Posted (Estimate)

March 2, 2010

Last Update Submitted That Met QC Criteria

March 1, 2010

Last Verified

March 1, 2010

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Diabetes Mellitus, Type 2

Clinical Trials on caffeine administration

3
Subscribe