High-Intensity Exercise to Combat Vascular and Cognitive Dysfunction in Adults With HIV

Study Overview
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Brief Summary
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This is a single site, randomized exercise trial with individuals at least 50 years of age living with HIV who experience suboptimal cognition. The overall goals of this proposal are to determine whether 12 weeks of structured high-intensity interval training (HIIT) can overcome vascular and cognitive impairments (Aim 1) to a greater extent than continuous moderate exercise. Additionally, investigator will seek to identify barriers to engagement in exercise and the participants' perceptions of the study and exercise interventions (Aim 2). This study will enroll 60 participants in Birmingham, Alabama. Data collection will occur at each visit, with baseline data collected at the initial visit with a 3-month follow-up occurring following completion of the intervention.

Detailed Description
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This is a single site, randomized exercise trial with individuals at least 50 years of age living with HIV who experience suboptimal cognition. The overall goals of this proposal are to determine whether 12 weeks of structured high-intensity interval training (HIIT) can overcome vascular and cognitive impairments (Aim 1) to a greater extent than continuous moderate exercise. Additionally, investigator will seek to identify barriers to engagement in exercise and the participants' perceptions of the study and exercise interventions (Aim 2). This study will enroll 60 participants in Birmingham, Alabama. Vascular function will be measured using pulse wave velocity. Cognition will be assessed using the BRACE+. Additionally, perceptions of exercise and the study as well as barriers to engaging in exercise will be determined through the analysis qualitative interviews. The overall hypothesis is that HIIT will result in greater enhancements in vascular and cognitive function. The investigators expect that individuals randomized to HIIT will result in greater satisfaction with the protocol. Based on the data collected, the investigators seek to develop tailored intervention to promote successful aging among older people living with HIV.

Official Title
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A Pilot Trial of High-Intensity Exercise to Combat Vascular and Cognitive Dysfunction in Older Adults With HIV

Conditions
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HIV, Arterial Stiffness, Cognitive Dysfunction

Intervention / Treatment
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* Behavioral: High-Intensity Interval Training
* Behavioral: Continuous Moderate Exercise


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 50 years and older Sedentary lifestyle, deﬁned as < 150 min/wk moderate physical activity as assessed by CHAMPS questionnaire Neurocognitive Impairment (as assessed using the BRACE+ Prescribed HIV ART for ≥ 12 months, with no current use of older drugs with established mitochondrial toxicity Able to speak, read, and write in English Willingness to participate in all study procedures Exclusion Criteria: Diagnosis of mitochondrial disease Active substance abuse or factors preventing compliance or safety Uncontrolled hypertension, deﬁned as resting BP > 150/90 mmHG Chronic kidney disease Severe cardiac disease, including NYHA Class III or IV congestive heart failure, clinically signiﬁcant aortic stenosis, history of cardiac arrest, use of a cardiac deﬁbrillator, or uncontrolled angina Acute myocardial infarction identiﬁed by medical history and ECG Pulmonary disease requiring the use of supplemental oxygen Poorly controlled diabetes Neuropsychologically Intact Orthopedic problems that limit ability to perform exercise Simultaneous participation in another intervention trial

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Participants will be randomized to high-intensity interval training or continuous moderate exercise for 12 weeks.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: High-Intensity Interval Training<br> | Behavioral: High-Intensity Interval Training<br>* Exercise will be done on the stationary bicycle. For the HIIT group, following a warm-up at 50% of heart rate reserve (HRR) higher- and lower-intensity exercise bouts will alternate: five bouts of 4-minute vigorous-intensity exercise (up to 90% HRR) with four 3-minute bouts of moderate-intensity aerobic exercise (50% HRR). Both groups will complete a comparable cool-down period. From weeks 6 to 12, the aerobic exercise duration will be 45 minutes for HIIT. The intensity of exercise will progress over the first 6 weeks to reach the target goals, and this prescription will be maintained until the end of the end of the interventions.<br>|
| Active Comparator: Continuous Moderate Exercise<br> | Behavioral: Continuous Moderate Exercise<br>* Exercise will be done on the stationary bicycle. For the continuous-moderate exercise group, following a warm-up at 50% HRR, the participant will walk continuously at 60% HRR. HRR will be calculated using the supine resting heart rate and age-predicted max heart rate. Both groups will complete a comparable cool-down period. From weeks 6 to 12, the aerobic exercise duration will be 50 minutes for continuous-moderate exercise.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in vascular function | Arterial stiffness is a continuous measure of cardiovascular disease risk. | Baseline, Up to 12 weeks, 3-months Post-Intervention | 
| Change in cognitive function | Cognitive function will be measured using BRACE+, a neuropsychological battery | Baseline, Up to 12 weeks, 3-months Post-Intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Barriers to Engagement in Exercise | This will be assessed during qualitative interviews grounded in the Theoretical Domains Framework. | Baseline | 
| Perceptions of the Study and Exercise Interventions | This will be assessed during qualitative interviews grounded in the Theoretical Domains Framework. | Up to 12 weeks |