Insulin Nasal Spray May Slow Alzheimer’s Disease

Insulin is critical for normal brain function, and dysregulated insulin metabolism has been shown to contribute to the development of Alzheimer’s disease.  As well, patients with Alzheimer’s Disease also exhibit decreased levels of insulin in the central nervous system. Suzanne Craft, from the Veterans Affairs Puget Sound Health Care System (Washington, USA), and colleagues explored whether raising insulin levels to normal might help maintain cognitive ability. The team completed a three-week trial during which 104 subjects, average age 72 years, received 20 or 40 IU of insulin administered intranasally, daily for four months. Not only did the participants who received 20 IU of insulin daily exhibit improvements in delayed story recall and functional status, but baseline scores on a standardized dementia assessment scale were maintained over the study period in those who received either 20 IU or 40 IU of daily insulin.   Further, both doses of insulin led to preservation of function on an activities of daily living scale.  The researchers submit that: “These results support longer trials of intranasal insulin therapy for patients with amnestic mild cognitive impairment and patients with [Alzheimer’s Disease].”