Dr. Bradley's main contributions to the health of Canadians are his breakthroughs on the causes, consequences, treatment and diagnosis of sleep apnea. In patients with heart failure, he showed that sleep apnea reduces survival and its treatment may improve survival. He demonstrated that sleep apnea increases stroke risk, and its treatment improves stroke recovery. He also observed that fluid movement from the legs into the neck at night causes sleep apnea and reducing this fluid movement alleviates it. Finally, by developing a portable device for diagnosing sleep apnea at home, Dr. Bradley's team has increased accessibility to sleep apnea diagnosis.