Small vessel disease can occur in the brain’s white matter causing white spots or patches to show up on an MRI scan in 95 per cent of seniors. In 20 per cent it can be severe, slowing down thought processes and causing balance problems and falls, associated with aging and scarring of the small veins deep in the brain. Research has shown the importance of making people aware of changes they can make to their brain health, not only by control of hypertension and other vascular risks but also by including a healthy diet and exercise, which promotes healthy blood vessels in the brain and body and can help to offset the impact of stroke.
“As more people live to be an age where they are at very high risk for these dementias, they are a major challenge for our society,” says Dr. Black.
Dr. Swartz is currently testing a novel tool to screen stroke clinic patients for cognitive impairment, as well as depression and obstructive sleep apnea. These conditions each affect up to 50 percent of people after stroke, are associated with worse outcomes, less recovery, higher risks of future strokes yet are frequently under-assessed.
“These are very complex brain disorders and we have a long way to go, but in the last decade alone, it’s amazing the things we can do now,” says Dr. Black.
THE EMBRACE TRIAL
Sunnybrook’s stroke research made international headlines in February when a breakthrough study by Dr. David Gladstone revealed a significant portion of people who suffer unexplained strokes have silent atrial fibrillation.
This condition causes an irregular heartbeat — a major risk factor for stroke because it can cause blood clots to form in the heart which can travel to the brain. Catching this problem early could prevent many strokes, as these patients can be effectively treated with anti-clotting medications. Anti-clotting medications can cut the risk of clots and strokes by at least two-thirds.
The EMBRACE trial, conducted over three years and funded by the Canadian Stroke Network, is the world’s first and largest clinical trial to study advanced heart monitoring in stroke patients. The major finding of the study, says Dr. Gladstone, is that an advanced heart monitoring strategy led to a five-fold increase in detection of silent atrial fibrillation, and resulted in almost a doubling of patients who could be treated with anticoagulant therapy. One in six patients who underwent prolonged monitoring was found to have atrial fibrillation, which otherwise would have gone undetected and untreated.
These findings are forcing experts to rethink the diagnostic and treatment approaches for such patients with so-called "cryptogenic" strokes, a medical conundrum for years. A half-million stroke patients a year may have untreated atrial fibrillation and not know it.
Dr. Gladstone presented the trial at the International Stroke Conference in Honolulu, Hawaii, and sparked worldwide attention. “This study provides the strongest evidence to date to support the use of prolonged cardiac monitoring in elderly patients with unexplained strokes or stroke warning events when the standard diagnostic tests are unrevealing.”