Why do heart failure patients suffer depression, impaired thinking?

A new study by University of Guelph researchers explains why heart failure patients often have trouble with thinking and depression.

“Neurosurgeons always look in the brain; cardiologists always look in the heart. This new study looked at both,” says Tami Martino, a professor in U of G’s Department of Biomedical Sciences and director of the Centre for Cardiovascular Investigations.

Human patients with heart failure often have neurological conditions such as cognitive impairment and depression. Martino suspects the heart-brain connection involved the circadian mechanism molecule, called “clock.”

Circadian rhythms in humans and other organisms follow Earth’s 24-hour cycle of light and darkness, signalling when to sleep and when to be awake.

Researchers compared normal mice with mice carrying a mutation in their circadian mechanism. They found that the mutation affected the structure of neurons in brain areas important for cognition and mood. The team also found differences in clock regulation of blood vessels. The results were published recently in Nature Scientific Reports.