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

Cardiovascular Clinical Trial

Official title:

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

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00387452
• Other study ID #: H04-70001
• Secondary ID: ORSIL# 05-0820
• Status: Completed
• Phase: N/A
• First received: October 11, 2006
• Last updated: April 12, 2017
• Start date: February 2006
• Est. completion date: April 2012

Study information

• Verified date: April 2017
• Source: University of British Columbia
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

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).

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 64
• Est. completion date: April 2012
• Est. primary completion date: April 2012
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 65 Years and older

Eligibility

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

Related Conditions & MeSH terms

• Cardiovascular
• Diabetes Mellitus, Type 2
• Diabetic

Intervention

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.
• 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.

Locations

Country	Name	City	State
Canada	Vancouver General Hospital Research Pavilion	Vancouver	British Columbia

Sponsors (2)

Lead Sponsor	Collaborator
University of British Columbia	Canadian Institutes of Health Research (CIHR)

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Pulse wave velocity (central and peripheral)		Unspecified
Primary	Drop in middle cerebral artery velocity with upright tilting		Unspecified
Primary	Drop in blood pressure with upright tilt		Unspecified
Primary	Arterial baroreflex sensitivity		Unspecified
Primary	Time and frequency domain measures of heart rate variability		Unspecified
Secondary	Fasting blood glucose, HgbA1C		Unspecified
Secondary	VO2max		Unspecified
Secondary	Dynamometry measures of muscle strength		Unspecified
Secondary	Resting and maximal heart rate		Unspecified
Secondary	Waist to hip ratio, BMI		Unspecified
Secondary	Lean body mass/% fat		Unspecified
Secondary	Catecholamines		Unspecified
Secondary	Increase in Gosling's pulsatility index		Unspecified
Secondary	Linear transfer-function analysis of cerebral autoregulation during upright tilt		Unspecified