NCT00701051

Brief Summary

Diabetes and its associated complications affect more than 20 million Americans, and the prevalence of type 2 diabetes and impaired glucose tolerance rises dramatically with age such that 40% of Americans over age 60 are affected. In older adults, glucose metabolism may be affected by reduced skeletal muscle capillary supply, which limits insulin, glucose, and oxygen delivery to skeletal muscle. Reduced capillary supply to skeletal muscle is found in older individuals with impaired glucose tolerance and we hypothesize that this is due to reduced vascular growth factor expression, and chronic inflammation. Further, we hypothesize that reversal of a sedentary lifestyle through aerobic exercise training will increase insulin signaling and vascular growth factor expression, as well as decrease inflammation, to increase capillary supply to skeletal muscle, which contributes to improved glucose metabolism in older adults. This study will: 1) Determine the mechanisms underlying reduced skeletal muscle capillarization in older adults with impaired glucose tolerance; and 2) Determine the effect of aerobic exercise training-induced increases in skeletal muscle capillarization on glucose metabolism in older adults.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
90

participants targeted

Target at P50-P75 for not_applicable type-2-diabetes-mellitus

Timeline
Completed

Started Oct 2006

Longer than P75 for not_applicable type-2-diabetes-mellitus

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

October 1, 2006

Completed
1.7 years until next milestone

First Submitted

Initial submission to the registry

June 18, 2008

Completed
1 day until next milestone

First Posted

Study publicly available on registry

June 19, 2008

Completed
4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 1, 2012

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

June 1, 2012

Completed
2.8 years until next milestone

Results Posted

Study results publicly available

April 6, 2015

Completed
Last Updated

April 6, 2015

Status Verified

March 1, 2015

Enrollment Period

5.7 years

First QC Date

June 18, 2008

Results QC Date

January 26, 2015

Last Update Submit

March 23, 2015

Conditions

Outcome Measures

Primary Outcomes (4)

  • Baseline Glucose Utilization

    Insulin-stimulated glucose uptake

    baseline

  • Glucose Utilization (Pre/Post Intervention)

    Insulin-stimulated glucose uptake

    baseline, 24 weeks, 26 weeks

  • Baseline Skeletal Muscle Capillarization

    baseline

  • Skeletal Muscle Capillarization (Pre/Post Intervention)

    baseline, 24 weeks, 26 weeks

Secondary Outcomes (5)

  • Baseline 2-hour Postprandial Glucose

    baseline

  • 2-hr Post-prandial Plasma Glucose Level

    baseline, 24 weeks, 26 weeks

  • Baseline Cardiorespiratory Fitness

    baseline

  • Cardiorespiratory Fitness

    baseline, 24 weeks, 26 weeks

  • Body Composition (%Fat)

    baseline, 24 weeks

Study Arms (2)

Arm 1

ACTIVE COMPARATOR

Older adults, normal glucose tolerance

Behavioral: Aerobic exercise trainingBehavioral: Detraining (cessation of exercise)

Arm 2

EXPERIMENTAL

Older adults, impaired glucose tolerance

Behavioral: Aerobic exercise trainingBehavioral: Detraining (cessation of exercise)

Interventions

24 weeks of aerobic exercise training: 3 times per week, 60 minutes per session, at 70% of maximal aerobic capacity

Arm 1Arm 2

Cessation of exercise for 2 weeks

Arm 1Arm 2

Eligibility Criteria

Age50 Years - 75 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Age 50-75 years
  • Non-smoker \>2 years
  • Body mass index = 18-35 kg/m2

You may not qualify if:

  • History of CAD or cerebrovascular disease that would preclude exercise
  • Implantable defibrillator
  • Active cancer
  • Chronic pulmonary, thyroid, renal, liver, or hematological disease
  • HIV positive or prone to malnutrition
  • Sickle cell anemia
  • Type 1 diabetes, or currently on medication to treat type 2 diabetes
  • Poorly-controlled type 2 diabetes
  • Poorly-controlled hypertension
  • Taking medications including: beta-blockers, oral steroids, warfarin, certain statins, hormone replacement therapy (HRT), oral contraceptives (OCP), thiazolidinediones (TZD), or chronic steroids or nonsteroidal analgesics (NSAIDS) that may not be safely discontinued temporarily for specific procedures (i.e. for 72 hours prior)
  • Allergic to lidocaine or heparin
  • Recent weight change (\>5kg in 3 months)
  • Currently pregnant or nursing
  • Physical impairment limiting exercise
  • Dementia or unstable clinical depression

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

VA Maryland Health Care System, Baltimore

Baltimore, Maryland, 21201, United States

Location

Related Publications (1)

  • Prior SJ, Goldberg AP, Ortmeyer HK, Chin ER, Chen D, Blumenthal JB, Ryan AS. Increased Skeletal Muscle Capillarization Independently Enhances Insulin Sensitivity in Older Adults After Exercise Training and Detraining. Diabetes. 2015 Oct;64(10):3386-95. doi: 10.2337/db14-1771. Epub 2015 Jun 11.

MeSH Terms

Conditions

Diabetes Mellitus, Type 2Glucose IntolerancePrediabetic State

Condition Hierarchy (Ancestors)

Diabetes MellitusGlucose Metabolism DisordersMetabolic DiseasesNutritional and Metabolic DiseasesEndocrine System DiseasesHyperglycemia

Results Point of Contact

Title
Steven J. Prior, PhD
Organization
Baltimore VA Medical Center

Study Officials

  • Steven J. Prior, PhD

    VA Maryland Health Care System, Baltimore

    PRINCIPAL INVESTIGATOR

Publication Agreements

PI is Sponsor Employee
Yes

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NON RANDOMIZED
Masking
NONE
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
FED
Responsible Party
SPONSOR

Study Record Dates

First Submitted

June 18, 2008

First Posted

June 19, 2008

Study Start

October 1, 2006

Primary Completion

June 1, 2012

Study Completion

June 1, 2012

Last Updated

April 6, 2015

Results First Posted

April 6, 2015

Record last verified: 2015-03

Locations