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

April 12, 2017 updated by: Kenneth Madden, University of British Columbia
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).

Study Overview

Status

Completed

Conditions

Intervention / Treatment

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.

Study Type

Interventional

Enrollment (Actual)

64

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

  • Canada
    • British Columbia
      • Vancouver, British Columbia, Canada, V5Z 1L8
        • Vancouver General Hospital Research Pavilion

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

65 years and older (Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

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

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: Other
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
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.
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.
No Intervention: 3
No intervention, only testing during 6 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Pulse wave velocity (central and peripheral)
Drop in middle cerebral artery velocity with upright tilting
Drop in blood pressure with upright tilt
Arterial baroreflex sensitivity
Time and frequency domain measures of heart rate variability

Secondary Outcome Measures

Outcome Measure
Fasting blood glucose, HgbA1C
VO2max
Dynamometry measures of muscle strength
Resting and maximal heart rate
Waist to hip ratio, BMI
Lean body mass/% fat
Catecholamines
Increase in Gosling's pulsatility index
Linear transfer-function analysis of cerebral autoregulation during upright tilt

Collaborators and Investigators

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

Sponsor

University of British Columbia

Collaborators

Canadian Institutes of Health Research (CIHR)

Investigators

  • Principal Investigator: Kenneth Madden, MD, University of British Columbia

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 (Actual)

February 1, 2006

Primary Completion (Actual)

April 1, 2012

Study Completion (Actual)

April 1, 2012

Study Registration Dates

First Submitted

October 11, 2006

First Submitted That Met QC Criteria

October 11, 2006

First Posted (Estimate)

October 13, 2006

Study Record Updates

Last Update Posted (Actual)

April 14, 2017

Last Update Submitted That Met QC Criteria

April 12, 2017

Last Verified

April 1, 2017

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • H04-70001
  • ORSIL# 05-0820

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

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.

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