Grant: Project Grant

After surgery, older people frequently experience acute confusion (delirium) and persistent cognitive changes, which result in loss of autonomy. Whether and why surgery increases the risk of cognitive dysfunction is unclear yet. In a study of 1114 65+ patients undergoing noncardiac surgery (NeuroVISION-1), we showed that 7% had a new silent brain infarct (i.e., covert stroke) on brain MRI around the time of surgery. Cognitive decline at 1 year occurred frequently in those without a covert stroke (29%), but significantly more frequently in those with a covert stroke (42%). Perioperative covert stroke also increased the risk of delirium, and stroke or TIA within 1 year. Atrial fibrillation (AF) is a common heart rhythm abnormality and can cause stroke in older non-surgical populations. AF occurs frequently after surgery, often silently. We will conduct the NeuroVISION-2 study in order to determine whether perioperative AF is associated with perioperative covert stroke; whether perioperative hypotension and hypoxia are associated with delirium and cognitive decline at 1 year also in absence of a covert stroke; whether there are molecules that can detect or predict these complications; and whether surgery does increase the risk of acute cover stroke and long-term cognitive decline. We will enroll 1300 patients 65 years old or older undergoing elective non-cardiac surgery, who will have technology applied to collect continuous data about their heart rhythm, blood pressure, and oxygen level until 30 days after surgery; will undergo a brain MRI; and will be assessed for delirium in hospital, and for cognitive changes at 1 year compared to baseline. This surgical cohort will be matched and compared with 1300 concurrent 65+ non-surgical patients, and with non-surgical cohorts from other existing studies. NeuroVISION-2 will help understand and prevent complications after surgery that are very distressing for patients and their families.