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Exercise and Cardiovascular Control During Upright Tilt in Older Adults With Type 2 Diabetes

This study is currently recruiting participants.
Verified December 2011 by University of British Columbia
Sponsor:
Collaborator:
Canadian Institutes of Health Research (CIHR)
Information provided by (Responsible Party):
University of British Columbia
ClinicalTrials.gov Identifier:
NCT00387452
First received: October 11, 2006
Last updated: December 12, 2011
Last verified: December 2011
History of Changes
  Purpose

Older persons with diabetes have a harder time maintaining blood pressure when standing up. When blood pressure drops when standing up, fainting may occur. This study will see how regular exercise can improve the ability of the body to keep blood pressure up when standing. We want to see how this improvement varies with different types of exercise. The types of exercise that we will be studying are aerobic (running or cycling on a stationary bike) and strength training (weight lifting).


Condition Intervention
Cardiovascular
Diabetic
 Behavioral: Aerobic Exercise and Strength Exercise
Behavioral: Strength training

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Official Title: Exercise and Cardiovascular Control During Upright Tilt in Older Adults With Type 2 Diabetes

Resource links provided by NLM:

U.S. FDA Resources

Further study details as provided by University of British Columbia:

Primary Outcome Measures:
  • Pulse wave velocity (central and peripheral) [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Drop in middle cerebral artery velocity with upright tilting [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Drop in blood pressure with upright tilt [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Arterial baroreflex sensitivity [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Time and frequency domain measures of heart rate variability [ Time Frame: Unspecified ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Fasting blood glucose, HgbA1C [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • VO2max [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Dynamometry measures of muscle strength [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Resting and maximal heart rate [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Waist to hip ratio, BMI [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Lean body mass/% fat [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Catecholamines [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Increase in Gosling's pulsatility index [ Time Frame: Unspecified ] [ Designated as safety issue: No ]
  • Linear transfer-function analysis of cerebral autoregulation during upright tilt [ Time Frame: Unspecified ] [ Designated as safety issue: No ]

Estimated Enrollment: 60
Study Start Date: February 2006
Estimated Study Completion Date: December 2012
Estimated Primary Completion Date: December 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 1 Behavioral: Aerobic Exercise and Strength Exercise
6 months of aerobic training exercise. regulated by heart rate; work up to 80% of maximal heart rate on treadmill or stationary bike; 3 hours a week, 90% attendance.
Active Comparator: 2 Behavioral: Strength training
6 months of strength training exercise using weight machines involving legs and arms: 12-15 repetitions of weights per exercise; 3 hours a week, 90% attendance.
No Intervention: 3
No intervention, only testing during 6 months.

Detailed Description:
  1. PURPOSE: Older adults with diabetes faint frequently, due to an impairment in the cardiovascular control mechanisms (arterial baroreceptor function, autonomic nervous system function and cerebral autoregulation) that prevent syncope. The purpose of this study is to examine the ability of different intensities of aerobic exercise to reverse these impairments.

  2. HYPOTHESES: a) Aerobic or strength training will improve the compensatory cardiovascular responses that prevent syncope in older adults with Type 2 diabetes. Aerobic training will:

    • increase arterial baroreflex sensitivity
    • increase heart rate variability (marker of autonomic nervous system function)
    • decrease cerebrovascular resistance

    • improve cerebral autoregulation during upright tilt. b) There will be relationship between the improvement in compensatory cardiovascular responses and aerobic or strength training.

      c) The majority of the benefits of aerobic or strength exercise on the above parameters will with which training, allowing for the design of more practicable training prescriptions than that used in a research setting.

  Eligibility

Ages Eligible for Study:   65 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Type 2 diabetes for at least 5 years treated with diet alone or oral agents Nonsmoker for at least 5 years Subjects must be sedentary BMI between 24 and 35 All subjects will have a fasting glucose of <12 mM and a hemoglobin A1c < 8.5% All subjects must have developed hypertension CDA guidelines (systolic greater than 130 or diastolic greater than 80)

Exclusion Criteria:

  • Abnormalities on complete blood count, electrolytes or creatinine, on resting ECG, treadmill exercise stress test Significant pulmonary, exercise-limiting orthopedic or neurological impairment Evidence of valvular disease, exercise-induced syncope, angina, arrhythmias or peripheral vascular disease Poor blood pressure control as defined as systolic blood pressure greater than or equal to 160 mm Hg or diastolic blood pressure greater than or equal to 90 mm Hg Total cholesterol/HDL cholesterol greater than or equal to 5.0 or LDL cholesterol greater than or equal to 4.21 mmol/L Peripheral neuropathy severe enough to cause discomfort (for safety reasons) Significant orthostatic hypotension defined as a drop in systolic blood pressure greater than 30 mmHg during one of five consecutive arterial blood pressure readings immediately after changing position from lying to standing for safety.

Overt diabetic nephropathy excluding subjects with a urine albumin to creatinine ratio of greater than 2.0 in men or 2.8 in women Diabetic retinopathy

  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00387452

Contacts
Contact: Chris Lockhart 604-875-4111 ext 68535 lockhart@interchange.ubc.ca

Locations
Canada, British Columbia
Vancouver General Hospital Research Pavilion Recruiting
Vancouver, British Columbia, Canada, V5Z 1L8
Contact: Chris Lockhart     604-875-4111 ext 68535     lockhart@interchange.ubc.ca    
Principal Investigator: Kenneth Madden, Ph.D            
Sponsors and Collaborators
University of British Columbia
Canadian Institutes of Health Research (CIHR)
Investigators
Principal Investigator: Kenneth Madden, Ph.D University of British Columbia
  More Information

No publications provided

Responsible Party: University of British Columbia
ClinicalTrials.gov Identifier: NCT00387452     History of Changes
Other Study ID Numbers: CO4-0001, ORSIL# 05-0820
Study First Received: October 11, 2006
Last Updated: December 12, 2011
Health Authority: Canada: Health Canada

Keywords provided by University of British Columbia:
Aging
Type 2 diabetes
exercise
aerobic training
strength training
glucose metabolism arterial baroreceptors
 heart rate variability
cerebral autoregulation
tilt table study
transcranial Doppler
autonomic nervous system

Additional relevant MeSH terms:
Diabetes Mellitus, Type 2
Diabetes Mellitus
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases

ClinicalTrials.gov processed this record on May 16, 2013