N/A N=16 Treatment

American Heart Association- Stroke/Hypoxia Study

Stroke

Bottom Line

View on ClinicalTrials.gov: NCT04019522 ↗

Enrolled (actual)

Serious AEs

0.0%

Results posted

Apr 2026

Primary outcome: Primary: Number of Participants With Adverse Events — 1; 11; 2; 10 Participants

Study Design & Population

Study type: Interventional
Phase: N/A
Interventions: Acute Intermittent Hypoxia (AIH) (Other)
Age: Adult, Older Adult · 18+ yrs
Sex: All
Sponsor: Shirley Ryan AbilityLab
Primary completion: Feb 2022

Outcome Measures

Outcome	Result	p-value
PRIMARY Number of Participants With Adverse Events	1; 11; 2; 10; 1; 11	—
SECONDARY National Institute of Health Stroke Scale (NIHSS)	-0.3	—
SECONDARY Fugl- Meyer Assessment	-1.6	—
SECONDARY Modified Ashworth Scale	-0.1	—
SECONDARY Grip Strength	4.38; 1.6	—
SECONDARY Pinch Strength	1.7; 2.1	—
SECONDARY Elbow Strength	7.9; 8.3	—
SECONDARY D-KEFS Color-Word Interference Test	-0.1	—
SECONDARY 5 Minute Neurological Test	10	—

Summary

Of the 795,000 people who experience a stroke every year in the US, only a small percentage will achieve full recovery. While current therapies promote strength and endurance, none directly address the unique potential of the brain to reorganize following injury. The goal of this project is to explore the effects of a novel therapy, acute intermittent hypoxia (AIH). During this therapy, individuals receive brief bouts of reduced oxygen levels by inhalation through a face mask. (This is akin to being on top of a tall mountain). In brief exposures, AIH is known to trigger the release of specific proteins that help the brain adapt to oxygen reductions. Published results in people with incomplete spinal cord injury have shown that AIH enhances muscle strength and coordination rather quickly. The research team aims to study the effects of AIH in stroke survivors.

Eligibility Criteria

Inclusion criteria

Age ≥18 years;

A first time, unilateral, ischemic, hemispheric stroke, confirmed by magnetic resonance imaging (MRI);

Chedoke assessment > 3

Ability to open and close affected hand

Able to understand and communicate in English

Be able to consent independently

≥ 6 months post stroke

Must have a hemoglobin level above 10g/dl (to be confirmed using handheld noninvasive lab equipment)

Must have ability to attend research visits with a companion for assistance

WOCBP must be comfortable confirming negative pregnancy prior to hypoxia experimental therapy.

Exclusion criteria

Brain stem or cerebellar stroke; mean Fazekas score rated on initial fluid-attenuated inversion recovery MRI ≥3

Severe aphasia, preventing subject from understanding the protocol and giving written consent;

History of prior neurological disorder;

Pre-existing hypoxic pulmonary disease,

Severe hypertension (>160/100)

Ischemic cardiac disease.

View full record on ClinicalTrials.gov →

Data sourced from ClinicalTrials.gov (NCT04019522). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.