Researchers at the University of Washington, in Seattle, carried out a small randomised controlled trial with 40 people with Alzheimer’s disease and 64 with amnestic mild cognitive impairment (aMCI) – memory problems that do not interfere with everyday life. A third of the group received daily doses of 20 IU (international units) of insulin in a nasal spray for four months, while a third received 40 IU doses and a third were given a placebo. None of the participants had diabetes.
They found those who were given 20 IU of insulin performed better on memory tests than those who had the placebo, while those who were given the higher dose of insulin showed no improvement. Scores on the Dementia Severity Rating Scale were preserved in those who took insulin, while scores for the placebo group worsened.
The researchers, whose findings are published online in Archives of Neurology, now want to see longer trials to test the treatment.
Dr Simon Ridley, Head of Research at Alzheimer’s Research UK, said:
“It’s long been known that diabetes and Alzheimer’s are linked, but we still need to know much more about the role of insulin in Alzheimer’s disease. This is an encouraging small study, but we would need to see larger, long-term trials before we can draw any firm conclusions on whether this treatment could be helpful in Alzheimer’s.”
“Current drugs for Alzheimer’s only treat some of the symptoms, and we still desperately need to find a treatment that can halt the disease in its tracks. With 820,000 people affected by dementia in the UK today, we need to see many more treatments being trialled if we are to offer the best hope for the future.”
Alzheimer’s Research UK