Introduction: Intermittent hypoxic–hyperoxic training (IHHT) may complement a multimodal training intervention (MTI) for improving cognitive function and exercise tolerance in geriatric patients. Methods: Thirty‐four patients (64–92 years) participated in this randomized controlled trial. Before and after the 5‐ to 7‐week intervention period (MTI + IHHT vs. MTI + ambient air), cognitive function was assessed by the Dementia‐Detection Test (DemTect) and the Sunderland Clock‐Drawing Test (CDT), and functional exercise capacity by the total distance of the 6‐Minute Walk Test (6MWT). Results: DemTect and CDT indicated significantly larger improvements after MTI + IHHT (+16.7% vs. −0.39%, P < .001) and (+10.7% vs. −8%, P = .031) which was also true for the 6MWT (+24.1% vs. +10.8%, P = .021). Discussion: IHHT turned out to be easily applicable to and well tolerated by geriatric patients up to 92 years. IHHT contributed significantly to improvements in cognitive function and functional exercise capacity in geriatric patients performing MTI.

To compare a program based on intermittent hypoxia-hyperoxia training (IHHT) consisting of breathing hypoxic-hyperoxic gas mixtures while resting to a standard exercise-based rehabilitation program with respect to cardiorespiratory fitness (CRF) in older, comorbid cardiac outpatients. Thirty-two cardiac patients with comorbidities were randomly allocated to IHHT and control (CTRL) groups. IHHT completed a 5-week program of exposure to hypoxia-hyperoxia while resting, CTRL completed an 8-week tailored exercise program, and participants in the CTRL were also exposed to sham hypoxia exposure. CRF and relevant hematological biomarkers were measured at baseline and after treatment in both groups. After intervention, CRF in the IHHT group was not significantly different (n = 15, 19.9 ± 6.1 mlO₂ minutes^-1 kg^-1) compared with the CTRL group (n = 14, 20.6 ± 4.9 mlO₂ minutes^-1 kg^-1). CRF in IHHT increased significantly from baseline (6.05 ± 1.6 mlO₂ minutes^-1 kg^-1), while no difference was found in CTRL. Systolic and diastolic blood pressures were not significantly different between groups after treatment. Hemoglobin content was not significantly different between groups. Erythrocytes and reticulocytes did not change pre/post interventions in both experimental groups. IHHT is safe in patients with cardiac conditions and common comorbidities and it might be a suitable option for older patients who cannot exercise. A 5-week IHHT is as effective as an 8-week exercise program in improving CRF, without hematological changes. Further studies are needed to clarify the nonhematological adaptations to short, repeated exposure to normobaric hypoxia-hyperoxia.

Background: Once used by mountaineers to facilitate rapid adaptations to altitude and by athletes to improve their aerobic capacity, exposure to hypoxia has been proven to affect various physiological, clinically relevant parameters. A form of conditioning known as Intermittent Hypoxia Conditioning (IHC) consists of repeated exposures to intermittent hypoxia, combined with normoxia and hyperoxia, which has been shown to have potential as a treatment to improve cardio- metabolic risks profile in cardiac patients but results across studies are inconsistent. This systematic review and meta-analysis aimed to evaluate the clinical effectiveness of IHC. Methods: Four electronic databases (PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials) were searched (from inception to December 2019) to retrieve all studies focused on IHC in elderly patients with cardiovascular disease. A meta-analysis of functional, efficacy and safety outcomes in cardiac patients was completed to compare IHC to sham treatments. Results: Fourteen studies with 320 patients in the Interval Hypoxia-normoxia Group (IHNG) or Interval Hypoxia-hyperoxia training Group (IHHG) and 111 patients in the control group were included in our meta-analysis. IHNT and IHHT were associated with significant reduction in heart rate, SBP, and DBP at rest after treatment [MD= -5.35 beat/min, 95% CI (-9.19 to -1.50), p=0.006], [MD= -13.72 mmHg, 95% CI (-18.31 to -9.132), p<0.001], and [MD= -7.882 mmHg, 95% CI (-13.163 to -2.601), p=0.003], respectively. There were no significant complications or serious adverse events related to IHNT/IHHT. Conclusion: The current evidence suggested that the use of the IHNT/IHHT program in elderly patients with CVDs can be safe and effective in terms of heart rate and elevated blood pressure. However, currently, there is no supporting evidence that IHNT/IHHT can significantly improve hematological parameters or lipid profile. Exercise tolerance increased at the end of the course of hypoxic conditioning within IHC group, but did not differ from controls. Further research is needed.

Additional benefits of passive exposures to intermittent hypoxia and hyperoxia on cognitive performance and functional exercise capacity have been demonstrated in geriatric patients who performed a multimodal training program. The main goal of the present study was to evaluate effects of adding intermittent hypoxic-hyperoxic training (IHHT) to a multimodal training intervention (MTI) on mobility and perceived health in old individuals at a Geriatric Day Hospital. Thirty-four patients between 64 and 92 years participated in the double blind, randomized and controlled clinical trial. The elderly patients attended in a 5–7 weeks lasting MTI (strength, endurance, balance, reaction, flexibility, coordination, and cognitive exercises) and performed IHHT (breathing 10–14% oxygen for 4–7 min followed by 2–4 min 30–40% oxygen) in the Hypoxic Group (HG) or placebo treatment with ambient air in the Normoxic Group (NG) in parallel. Before and after all treatments, mobility was assessed by the Tinetti Mobility Test (TMT), the Timed-Up-and-Go Test (TUG) and Barthel-Index, while perceived health was assessed by one part of the EQ-5D Test, the EQ visual analogue scale (EQ VAS). After the MTI plus IHHT or normoxia sessions, results of the TMT, TUG, Barthel Index and EQ-VAS revealed no significant difference between HG and NG (+ 14.9% vs + 15.4%, p = 0.25; − 21% vs − 26.3%, p = 0.51; + 4.2% vs + 3.6%, p = 0.56; + 37.9% vs + 33.9%, p = 0.24;). IHHT added to MTI did not elicit additional improvements in perceived health and mobility compared to MTI alone.