NCT04854122

Blood Flow Regulation in Individuals With Down Syndrome - Training Study

Completed NA Results posted Last updated 4 February 2026

What this trial tests

NA trial testing Combined exercise intervention in Down Syndrome in 60 participants. Completed in 31 August 2024.

Timeline

9 September 2021

Primary endpoint
31 August 2024

31 August 2024

Quick facts

Lead sponsor	University of Nevada, Las Vegas
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	none
Primary purpose	supportive care
Enrollment	60
Start date	9 September 2021
Primary completion	31 August 2024
Estimated completion	31 August 2024
Sites	1 location across United States

Drugs / interventions tested

• Combined exercise intervention
• Usual care / Sham intervention

Conditions studied

• Down Syndrome — all drugs for Down Syndrome →

Sponsor

University of Nevada, Las Vegas

Who can join

Adults 18 to 35, any sex, with Down Syndrome. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Change From Baseline Work Capacity at 13 Weeks Primary · 13 weeks

Change in work capacity from baseline to 13 weeks, as measured by peak oxygen uptake in ml/kg/min with a graded exercise test on a treadmill.

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	-1.20	± 6.89
Usual Care Down Syndrome	-0.18	± 6.89

Change From Baseline Brachial Blood Flow at 13 Weeks Secondary · 13 weeks

Forearm blood flow and vascular conductance was measured in both the exercising and non-exercising arm using high definition ultrasound (Alpha 7, Aloka-Hitachi). The brachial artery was imaged in dual mode allowing for simultaneous determination of artery diameter (B-mode) and flow velocity (Doppler mode). Blood flow was determined from the following formula: Forearm Blood flow = (Mean blood velocity) x (Brachial Cross Sectional Area) x (60) and expressed as ml/min. Change from baseline to 13 weeks was presented.

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	24.66	± 77.57
Usual Care Down Syndrome	-15.87	± 77.57

Change From Baseline Muscle Oxygenation at 13 Weeks Secondary · 13 weeks

Muscle oxygenation was measured with near-infrared spectrography (NIRS), which is a simple, noninvasive method for measuring the presence of oxygen in muscle. It monitored changes in muscle oxygenation and blood flow during submaximal and maximal exercise. During exercise, the extent to which skeletal muscles deoxygenate varies according to the type of muscle, type of exercise and blood flow response. We analyzed the change from baseline to 13 weeks in percentage of oxygenated blood during hand grip exercise at 30% of maximal voluntary contraction (HGE 30%MVC).

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	-5.27	± 12.36
Usual Care Down Syndrome	0.49	± 4.03

Change From Baseline Cardiac Output (Aortic Blood Flow) at 13 Weeks Secondary · 13 weeks

Change from baseline to 13 weeks in cardiac output will be measured during a graded maximal test protocol. The ascending aortic blood flow will be measured using continuous Doppler echocardiography using a pedoff probe in the suprasternal notch.

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	4.26	1.24 – 7.28
Usual Care Down Syndrome	0.84	0.57 – 1.12

Change From Baseline Autonomic Cardiac Function at Rest at 13 Weeks Secondary · 13 weeks

Change from baseline to 13 weeks in clinical autonomic function test: heart rate variability during rest measured in root mean square of successive differences (RMSSD) in ms.

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	-7.40	± 18.52
Usual Care Down Syndrome	3.71	± 13.65

Change From Baseline Autonomic Cardiac Function During Orthostasis at 13 Weeks Secondary · 13 weeks

Change from baseline to 13 weeks in clinical autonomic function test: heart rate variability during orthostasis in root mean square of successive differences (RMSSD) in ms

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	20.33	± 26.34
Usual Care Down Syndrome	-4.43	± 14.47

Change From Baseline IL-6 at 13 Weeks Secondary · 13 weeks

Change from baseline to 13 weeks for interleukin-6 IL-6 (venous blood sample)

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	-0.75	± 2.30
Usual Care Down Syndrome	3.28	± 9.22

Change From Baseline HDL at 13 Weeks Secondary · 13 weeks

Change from Baseline in High-Density Lipoprotein in venous blood sample

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	-3.67	± 7.46
Usual Care Down Syndrome	-2.31	± 10.04

Change From Baseline Superoxide Dismutase at 13 Weeks Secondary · 13 weeks

Change from Baseline to 13 weeks in super oxide dismutase (venous blood sample)

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	-0.5510	± 2.42
Usual Care Down Syndrome	-0.1576	± 0.8743

Change From Baseline Comfortable Walking Speed at 13 Weeks Secondary · 13 weeks

Change from Baseline to 13 weeks in Comfortable walking speed in cm/sec

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	5.49	± 14.98
Usual Care Down Syndrome	1.27	± 18.31

Change From Baseline Fast Walking Speed at 13 Weeks Secondary · 13 weeks

Change from Baseline to 13 weeks in Fast Walking Speed in cm/sec

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	6.96	± 19.99
Usual Care Down Syndrome	-1.93	± 19.52

Change From Baseline Functional Reach at 13 Weeks Secondary · 13 weeks

Change from baseline to 13 week in Functional Reach, which is a balance test to investigate how far the participant can reach measured in cm.

Group	Value	95% CI
Combined Exercise Intervention Down Syndrome	-0.82	± 2.26
Usual Care Down Syndrome	0.17	± 2.41

Sponsor's own description

Work capacity is an important predictor of declining health or physical function, and of mortality, and is commonly measured as peak oxygen consumption. Peak oxygen consumption is very low in individuals with Down syndrome, the most prevalent genetic cause of intellectual disability. Previous research suggests individuals with Down syndrome may experience a double disadvantage when they are exercising: they may not be able to increase cardiac output sufficiently and they may not be able to allocate adequate blood flow to the working muscles. The aim of this research proposal is therefore to investigate the responses in central and peripheral blood flow regulation and cardiac autonomic function to exercise training in individuals with DS. Additionally the effects of exercise on gait, balance and attitude towards exercise in individuals with DS are investigated.

Publications & conference data

3 peer-reviewed publications reference this trial (live from Europe PMC):

1. The molecular mechanisms of cardiac development and related diseases.
   Li Y, Du J, Deng S, Liu B, et al · · 2024 · cited 53× · PMID 39715759 · DOI 10.1038/s41392-024-02069-8
2. Single-beat method echocardiographic comparison of ventricular-arterial coupling in adults with and without Down syndrome.
   Matthews A, Fernhall B, Hilgenkamp T. · · 2026 · PMID 41556835 · DOI 10.1152/ajpheart.01002.2025
3. Successful Online Exercise Intervention Studies for Individuals With Intellectual Disabilities Including Down Syndrome: Best Practices and Recommendations.
   Hilgenkamp T, Bodde A, Mann S, Helsel B, et al · · 2025 · PMID 40492527 · DOI 10.1111/jar.70080