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Dr. Manuel Montero-Odasso’s research demonstrates that gait testing, such as walking while performing a cognitively demanding task like counting backwards (dual-task gait),can be an effective predictor of progression to dementia. In a new study, a team at Lawson Health Research Institute and Western University’s Schulich School of Medicine & Dentistry has discovered changes to the brain that correspond to these findings. 

These changes identify a brain mechanism that corresponds with slow dual-task gait among older adults with mild cognitive impairment (MCI), an intermediate stage between the expected cognitive decline of normal aging and the more serious decline of dementia. Through their work Dr. Montero-Odasso and his team have found that a high dual-task gait cost, or a significant slowdown in walking speed when dual-tasking, is associated with a two- to three-fold increased risk of progression to dementia. However, the brain mechanism underlying this association was unclear.

To address this research question, Dr. Montero-Odasso partnered with Robert Bartha, PhD, an imaging scientist at Schulich Medicine & Dentistry and Robarts Research Institute at Western University. The team used magnetic resonance imaging (MRI) to examine the medial temporal areas of the brain, particularly the hippocampus, the parahippocampal gyrus, and the entorhinal cortex, which are regions particularly vulnerable to degeneration in Alzheimer’s disease. Participants were 40 older adults with MCI taking part in Dr. Montero-Odasso’s “Gait and Brain Study” at St. Joseph’s Health Care London’s Parkwood Institute. 

The researchers found that participants with higher dual-task gait costs had a smaller grey matter volume in the left entorhinal cortex. Although grey matter volume loss is a common finding in people with Alzheimer’s disease, it is still unclear which areas of the brain are first affected by neurodegeneration. This finding points to the entorhinal cortex as a susceptible brain region in early stages of cognitive decline. This is in line with previous studies reporting that progression to Alzheimer’s disease is associated with volume loss in the entorhinal cortex.

The study therefore suggests that cognitive and motor dysfunction in older adults with MCI share common changes to the brain. This further supports that dual-task gait changes may be a measurable motor marker for neurological degeneration happening in Alzheimer’s disease.

“These novel results show that early brain changes common to pre-dementia states can be manifested by the way patients walk,” says Dr. Montero-Odasso, scientist at Lawson, geriatrician at St. Joseph’s Health Care London, and professor at Schulich Medicine & Dentistry. “This evidence supports walking while performing a cognitively demanding task as an important way to help predict dementia.”

The study, “Entorhinal Cortex Volume Is Associated With Dual-Task Gait Cost Among Older Adults With MCI: Results From the Gait and Brain Study,” is published in The Journals of Gerontology: Series A.

Prostate cancer is the most commonly diagnosed cancer among Canadian men. However, with improved testing and better treatment options, the number of deaths from the disease has been declining over the last several years.

Scientists at Lawson Health Research Institute are working to continue this trend by testing improved prostate cancer imaging using a new molecule. Known as a Prostate Specific Membrane Antigen (PSMA) probe, the new molecule is used in Positron Emissions Tomography (PET) scans. The probe targets PSMA, a unique molecule on prostate cancer cells, to provide highly specific images for better diagnosis and management of patient disease.

PET probes are used in imaging to correctly diagnose cancer. The probes are injected into a patient where they spread to identify sites of disease. The most common PET probes are suitable for many types of cancer, but are not as sensitive in identifying prostate cancer. PSMA probes provide higher accuracy by targeting PSMA molecules, which are highly over-expressed on prostate cancer cells.

PSMA probes are gaining popularity across the globe. This specific probe is a molecule called 18F-DCFPyL and was developed by Dr. Martin Pomper at the John Hopkins Hospital in Baltimore. Dr. Pomper, also a Scientific Advisor to Lawson’s prostate imaging team, worked in collaboration with Canada’s Centre for Probe Development and Commercialization (CPDC) to bring the probe to our nation.

Lawson’s Canadian Institutes of Health Research (CIHR) Team in Image Guidance for Prostate Cancer gained early access to the PSMA probe due to a history of close collaboration with Dr. Pomper and the CPDC. Marking the first time a PSMA probe has been used in Canada, the team captured PET/MRI and PET/CT images from a 64-year-old prostate cancer patient on March 18, 2016 at St. Joseph’s Hospital.

“This is a tremendous step forward in the management of prostate cancer,” said Dr. Glenn Bauman, a Lawson scientist and Radiation Oncologist at London Health Sciences Centre. “PSMA probes have the potential to provide increased accuracy and detection which leads to better, personalized treatment.”

Lawson plans to study the probe with an additional 20 men over the next two years as part of an ongoing clinical trial funded by the Ontario Institute for Cancer Research (OICR). Lawson scientists are working with researchers across Ontario to develop other clinical trial protocols that will use 18F-DCFPyL to measure responses to drug treatments and to evaluate men with suspected recurrence of prostate cancer after radiotherapy.

“The goal of these studies it to establish the value of PSMA probes, particularly18F-DCFPyL, and provide evidence to support the use of these probes in routine clinical care,” said Dr. Bauman.

Donor funding through London Health Sciences Foundation was one catalyst in this research, providing initial funding to hire Research Associate, Catherine Hildebrand, who set up citywide cancer imaging workshops and helped the team prepare successful grant applications to secure key funding from CIHR and OICR.

With a drop of blood, Dr. Douglas Fraser and a team of Lawson and Western University researchers are changing the way we diagnose concussion.

In the past decade, rates of reported head injury have increased by more than 40 per cent in children and youth playing football, soccer and hockey. In that same time our understanding of the impacts of concussions has significantly increased.  Concussions can often result in severe symptoms and, in some individuals, long-term neurological dysfunction.  When ignored, these injuries can have lasting consequences.  As a result, concussions are a growing public health concern.

The diagnosis of a concussion can be difficult. Current tests rely on a patient’s description of their symptoms and the judgment of his or her physician. Concussions are sometimes misdiagnosed and some athletes with concussion return to sports too soon, putting them at risk of further injury.

By eliminating the guesswork in diagnosis, London researchers hope to improve patient outcomes.

Read the full story on the insideLHSC website.