London: A performance-enhancing hormone may improve cognitive functioning in patients suffering from bipolar disorder or depression, a new study has claimed.
The hormone EPO (erythropoietin), mostly produced by the kidney, is essential for the production of red blood cells.
EPO gives the blood a greater capacity to carry oxygen, and it is this characteristic which makes it attractive as a performance-enhancing drug.
“EPO treated patients showed a five times greater cognitive improvement from their individual baseline levels compared with placebo treated patients,” said lead researcher Kamilla Miskowiak, from Copenhagen University Hospital in Denmark.
Medically, recombinant EPO is used for the treatment of anemia.
This slow-down in thinking can have serious effects on sufferers, making it more difficult to retain a job, pass an exam, or maintain a relationship, researchers said.
In two randomised controlled trials, the researchers assessed cognitive function in 79 patients suffering from depression or bipolar disorder.
They assigned 40 of the patients to be given EPO for nine weeks, with the remaining 39 being given a placebo.
They found that EPO had beneficial effects on patients’ completion of a range of cognitive tests, including tests on verbal memory, attention span and planning ability.
Tests showed that this improvement was maintained for at least six weeks after treatment finished.
“EPO-treated patients showed 11 per cent improvement while placebo treated patients improved only by two per cent. This effect of EPO on cognition was maintained six weeks after patients had completed their treatment,” Miskowiak said.
It was found that patients who performed poorly in neuropsychological tests showed remarkably greater cognitive benefits when given EPO.
“This is interesting, as it means that we may be able to target patients for EPO treatment – and perhaps other future cognition treatments – based on how they do on neuropsychological tests,” said Miskowiak.