Muscle Lipid and Insulin Resistance in the Elderly - Full Text View

Sponsored by:	University of Pittsburgh
Information provided by:	University of Pittsburgh
ClinicalTrials.gov Identifier:	NCT00765505

Purpose

This project will provide novel information concerning the ability of exercise to enhance the capacity for oxidative metabolism of fatty acids and improve insulin resistance in older adults who are at high risk for the development of type 2 diabetes. Ultimately this may help identify mechanisms and therapeutic targets implicated in skeletal muscle metabolic dysregulation. The proposed study is to conduct a randomized controlled exercise training intervention trial in older men and women. In addition, the response to exercise in these subjects will be compared to those of highly endurance-trained, age-matched athletes.

Condition	Intervention
Obesity	Behavioral: Exercise Group Behavioral: Health Education Group

MedlinePlus related topics: Exercise and Physical Fitness Obesity

Drug Information available for: Insulin Lipids

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Treatment, Randomized, Open Label, Uncontrolled, Parallel Assignment
Official Title:	Muscle Lipid and Insulin Resistance in the Elderly

Further study details as provided by University of Pittsburgh:

Primary Outcome Measures:

Insulin sensitivity and muscle fat content will be measured at the beginning and the end of the intervention to determine the effects of exercise on these measures. [ Time Frame: 16 weeks ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

Examine if exercise-induced improvements in insulin sensitivity are similar in normal weight and in obese older subjects. [ Time Frame: 16 weeks ] [ Designated as safety issue: No ]

Estimated Enrollment:	300
Study Start Date:	July 2004
Estimated Study Completion Date:	December 2008
Primary Completion Date:	August 2008 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
1: Experimental Exercise Group	Behavioral: Exercise Group Sixteen week intervention where subjects will be progressed to four days per week for 45 minutes per session, 180 minutes minimum per week, of moderate intensity supervised exercise.
2: Experimental Health Education Group	Behavioral: Health Education Group Sixteen week intervention. This group will not receive specific exercise education or prescription but will be asked to participate in biweekly health education sessions

Detailed Description:

Hypothesis and Specific Aims:

To determine whether aerobic exercise improves both skeletal muscle fat distribution and insulin sensitivity of older men and women. We will test two hypotheses.

i. Physical exercise in older adults will decrease the amount of fat interspersed within muscle, specifically the fat between muscle groups (intermuscular adipose tissue) as well as decrease specific lipid metabolites within muscle cells, compared to controls.

ii. Exercise-induced improvements in insulin sensitivity of older men and women will be related to the changes in muscle fat content independent of changes in total body fat or visceral abdominal adipose tissue.
To determine whether increased capacity for oxidative fatty acid metabolism within muscle results in improved insulin sensitivity in older adults. We will test two hypotheses.

i. Exercise training will increase the capacity of muscle to oxidize fatty acids assessed both in vitro and in vivo.

ii. Improved capacity for oxidative fatty acid metabolism will predict improvements in insulin sensitivity.

Eligibility

Ages Eligible for Study:	60 Years to 75 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	Yes

Criteria

Inclusion Criteria:

60 - 70 years of age
No weight gain/loss of >10 lbs in 6 months
Sedentary (No more than 1 continuous exercise/week) or Highly trained (>5 exercise sessions/week for a duration of one year or more)
Non-Smoker
BMI 18-38.0
Resting blood pressure less than 150mmHg systolic/95 mmHg diastolic
Normal glucose tolerance: Fasting glucose < 100 mg/dl or 2 hour glucose from OGTT < 140 mg/dl or impaired glucose tolerance (fasting glucose > 100 mg/dl < 126 mg/dl or 2 hour glucose from OGTT > 140 mg/dl but less than 200 mg/dl
Note from PCP/Cardiologist for exercise clearance if positive stress test symptoms were observed from GXT

Exclusion Criteria:

Clinically significant CVD including h/o MI
Peripheral Vascular Disease
Hepatic, renal, muscular/neuromuscular, or active hematologic/oncologic disease
Clinically diminished pulse
Presence of bruits in lower extremities
Previous history of pulmonary emboli
Peripheral Neuropathy
Currently not engaged in a regular program and have a V)2 max pre-training value > 55 ml/kg-fat free mass-min., indicative of moderate fitness OR currently engaged in regular program and having a V)2 max value < 55 ml/kg-fat free mass-min.
Anemia (Hematocrit < 34%)
Any contraindications to moderate exercise
Inability and/or willingness to comply with the protocol as written
Active alcohol or substance abuse (Past 5 years)
Total cholesterol > 300 mg/dL
Triglyceride > 350 mg/dL
ALT > 80, AST > 80, Alk Phos > 240
Proteinuria (defined as > 1+ on routine dipstick) hypothyroidism (sTSH>8)
Therapeutic Doses of Nicotinic Acid
Type 2 Diabetes: Fasting Glucose > 126 mg/dl or 2 hour glucose > 200 mg/dl
Oral Glucocorticoids
Females currently on hormone replacement therapy (HRT) less than 6 months
Claustrophobia
Previous difficulty with lidocaine or other local anesthetic
Stress test symptoms:
- Positive ECG (>2mm ST segment depression) without PCP cardiologist permission to participate
- Signs or symptoms of cardiovascular decomposition (hypotensive response to exercise
- Onset of angina or angina like symptoms, shortness of breath, change in heart rhythm, signs of poor perfusion (light-headedness), tightness
- Hypotension

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00765505

Contacts

Contact: Jennifer Gabany, MSN, CRNP

412-578-9259

jmg115@pitt.edu

Locations

United States, Pennsylvania
University of Pittsburgh	Recruiting
Pittsburgh, Pennsylvania, United States, 15213

Sponsors and Collaborators

University of Pittsburgh

Investigators

Principal Investigator:

Bret H. Goodpaster, PhD

University of Pittsburgh

More Information

Responsible Party:	University of Pittsburgh ( Bret H. Goodpaster )
Study ID Numbers:	0405764, 5 R01 AG021961
Study First Received:	October 2, 2008
Last Updated:	October 2, 2008
ClinicalTrials.gov Identifier:	NCT00765505
Health Authority:	United States: Institutional Review Board

Keywords provided by University of Pittsburgh:

Insulin Resistance
Obesity
Exercise Training
Physical Activity

Study placed in the following topic categories:

Body Weight
Signs and Symptoms
Hyperinsulinism
Obesity
Metabolic Diseases
Nutrition Disorders

Overweight
Overnutrition
Insulin Resistance
Metabolic disorder
Glucose Metabolism Disorders
Insulin

ClinicalTrials.gov processed this record on January 13, 2009