Study evaluates intranasal insulin therapy for adults with mild cognitive impairment or Alzheimer's

September 12, 2011

Intranasal insulin therapy appears to provide some benefit for cognitive function in patients with amnestic mild cognitive impairment and Alzheimer disease, according to a report published Online First today by Archives of Neurology.

According to background information in the article, insulin plays a role in a number of functions of the central nervous system. "The importance of insulin in normal brain function is underscored by evidence that insulin dysregulation contributes to the pathophysiology of Alzheimer disease (AD), a disorder characterized in its earliest stages by synaptic loss and memory impairment," the authors write. " and insulin activity in the central nervous system are reduced in AD."

Suzanne Craft, Ph.D., of the Veterans Affairs Puget Sound Health Care System and the University of Washington School of Medicine, Seattle, and colleagues conducted a to evaluate the effects of intranasal insulin therapy on cognition, function, cerebral and cerebrospinal fluid biomarkers in adults with amnestic (aMCI) or AD.

Study participants were randomized into one of three treatment groups, with 36 participants receiving 20 IU (international unit) of insulin daily, 38 receiving 40 IU of insulin daily, and 30 participants receiving placebo daily for four months. All treatments were administered using a nasal drug delivery device. The authors evaluated the effects of treatment on delayed story recall (how well participants could recall a story told to them immediately after, and after a short time lapse) and the Dementia Severity Rating Scale (DSRS) scores of participants.

Compared with participants in the placebo-controlled group, those receiving 20 IU of insulin daily showed improved delayed story recall, however no improvement was observed for participants receiving 40 IU of insulin. Also, compared with the , DSRS scores were preserved for both groups. Both insulin doses also appeared to preserve general cognition for younger participants as assessed by the Alzheimer Disease's Assessment Scale–cognitive subscale (ADAS-cog) score as well as functional abilities in adults with AD as assessed by scores on the Alzheimer's Disease Cooperative Study–activities of daily living (ADCS-ADL) scale. Conversely, participants with aMCI showed no change regardless of treatment assignment and participants in the placebo-controlled group showed a slight decline overall in function.

"In conclusion, the results of our pilot trial demonstrate that the administration of intranasal insulin stabilized or improved cognition, function and cerebral glucose metabolism for adults with aMCI or AD," the authors write. "Taken together, these results provide an impetus for future clinical trials of intranasal and for further mechanistic studies of insulin's role in the pathogenesis of AD."

Explore further: Study finds older adults with mild cognitive impairment may also have some functional impairment

More information: Arch Neurol. Published online September 12, 2011. doi:10.1001/archneurol.2011.233

Related Stories

Recommended for you

New insights on how cocaine changes the brain

November 25, 2015

The burst of energy and hyperactivity that comes with a cocaine high is a rather accurate reflection of what's going on in the brain of its users, finds a study published November 25 in Cell Reports. Through experiments conducted ...

Can physical exercise enhance long-term memory?

November 25, 2015

Exercise can enhance the development of new brain cells in the adult brain, a process called adult neurogenesis. These newborn brain cells play an important role in learning and memory. A new study has determined that mice ...

Umbilical cells help eye's neurons connect

November 24, 2015

Cells isolated from human umbilical cord tissue have been shown to produce molecules that help retinal neurons from the eyes of rats grow, connect and survive, according to Duke University researchers working with Janssen ...

Brain connections predict how well you can pay attention

November 24, 2015

During a 1959 television appearance, Jack Kerouac was asked how long it took him to write his novel On The Road. His response – three weeks – amazed the interviewer and ignited an enduring myth that the book was composed ...

No cable spaghetti in the brain

November 24, 2015

Our brain is a mysterious machine. Billions of nerve cells are connected such that they store information as efficiently as books are stored in a well-organized library. To this date, many details remain unclear, for instance ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.