Lower brain tissue oxygenation puts frailer older adults with multi-morbidity at risk of faints and falls

Reviewed by Emily Henderson, B.Sc.Aug 18 2022

Researchers from Mercer's Institute for Successful Ageing (MISA) and the Department of Medical Physics at St James's Hospital and Trinity College Dublin have discovered that brain tissue oxygenation is lower in frailer older adults with multiple health conditions (multi-morbidity), putting them at risk of faints and falls. Brain oxygenation - the measure of oxygen in brain tissue - reflects the balance between oxygen delivery and consumption and is vital for the maintenance of normal brain function and tissue integrity. The research and its importance were recently recognized by a cover article in the Journal of the American Geriatric Society.

The study demonstrated in a group of 350 older adults that those with multiple chronic health conditions, especially women, are more prone to having both large blood pressure drops and lower brain oxygenation after standing up, increasing their risk of dizziness, faints and falls.

Key findings

• Multi-morbidity is associated with lower blood pressure after standing up. Monitors that measure blood pressure during every heartbeat play a key role in clinically assessing falls and faints.
• Multi-morbidity is also linked to large drops in brain oxygenation following standing up. Simple sensors that measure brain oxygenation could improve how dizziness, falls and faints are diagnosed and managed in the future, especially those who have multiple health conditions.

The study was carried out as part of a wider program of research examining new ways of detecting those at risk of faints using novel brain sensors and artificial intelligence tools. Brain oxygenation and blood pressure measurement may help us understand and manage multi-morbidity and how it leads to poor health outcomes such as faints and falls in older people.

This research was funded by the Irish Research Council and undertaken by PhD researcher, Ms Laura Perez-Denia, from the Department of Medical Gerontology, Trinity College Dublin, MISA and the Department of Medical Physics at St James's Hospital.

The work was led by study co-Principal Investigators Dr Ciarán Finucane, Clinical Senior Lecturer and Physicist at MISA, and Professor Rose Anne Kenny, Director of the Falls and Syncope Unit at MISA.

Ms Perez-Denia said:

"Falls and faints affect 1 in 3 older adults each year affecting their quality of life and increasing their risk of serious injury. Our work has discovered that new signs of accelerated brain aging can occur in those with common chronic health conditions placing these individuals at a higher risk of falling and consequently ill health. We have shown that these signs can be detected using novel brain sensor technologies which are both inexpensive and practical for clinical use opening up potential new avenues for clinical management."

These findings shed new light on some of the most common and potentially devastating conditions in older patients, with critical implications for diagnosing and managing falls and faints, both of which are the commonest causes of hip fractures and head injuries. Detection of intermittent low blood pressure and low brain oxygenation provide a novel approach to prevent serious disabilities and thereby maintain well-being and good health for longer."

Professor Rose Anne Kenny, study co-PI and Director of the Falls and Syncope Unit