HEART failure, which affects around 900,000 people in the UK, is linked to a decline in mental processes and a loss of grey matter in the brain, according to new research.

Experts behind a study found patients with heart failure suffered greater problems with their immediate and long-term memory and reaction speeds than healthy people.

They also experienced changes in parts of their brain thought to be important for memory, reasoning and planning.

The researchers said this could mean people cannot always remember simple tasks such as taking their daily medication.

Professor Osvaldo Almeida, from the University of Western Australia, said: "What we found in this study is that both ischaemic heart disease and heart failure are associated with a loss of cells in certain brain regions that are important for modulating emotions and mental activity.

"Our findings indicate that diseases that affect the heart affect the brain, and that the changes in organ function and blood circulation associated with heart failure seem to compound these effects in the brain."

Heart failure is a serious condition that describes what happens when the heart has trouble pumping enough blood around the body, often because it has become too weak or stiff.

The latest research, published in the European Heart Journal, analysed data for 35 people with heart failure, 56 with ischaemic heart disease and 64 healthy people acting as controls.

All were aged over 45 and did not suffer any obvious cognitive impairment.