People who have depression along with mild cognitive impairment and take the popular Alzheimer’s drug donepezil may help delay the progression to full-blown Alzheimer’s disease, according to new research.
“Our longer-term findings add to the body of evidence that suggests depression is a major risk factor for Alzheimer’s disease,” said Po H. Lu, an assistant professor of neurology at UCLA and an investigator in the study.
“Since the drug donepezil has been shown to improve the behavioral symptoms of Alzheimer’s disease, our study also tested whether the drug would delay the progression to Alzheimer’s disease in people with memory problems.”
Many people who age begin to suffer from mild problems in thinking or memory that is called “cognitive impariment.” Such impairment often occurs as a person is at the very earliest stages of Alzheimer’s disease, usually long before it is diagnosed.
People with mild cognitive impairment experience memory problems that are greater than expected from normal aging but do not show other symptoms of Alzheimer’s, such as difficulties completing everyday activities.
The three-year study followed 756 people between the ages of 55 and 91 who had mild cognitive impairment. Of those, 208 were diagnosed with depression using a test that measures the severity and intensity of depressive symptoms. For every one-point increase on the test, a participant’s risk of developing Alzheimer’s went up by 3 percent.
Study participants were given either vitamin E, donepezil or a placebo pill. Researchers found that among depressed people with mild cognitive impairment, 11 percent of those taking donepezil developed Alzheimer’s disease at 1.7 years, compared with 25 percent of those who took vitamin E or the placebo.
At just over 2 years, 14 percent of the donepezil group had developed Alzheimer’s, compared with 29 percent of the vitamin E and placebo groups.
Donepezil had little effect in the group of people who were not depressed.
“If we can delay the progression of this disease for even two years, it could significantly improve the quality of life for many people dealing with memory loss,” Lu said.
Donepezil is not approved by the U.S. Food and Drug Administration for use in treating mild cognitive impairment. The drug, however, is indicated for mild-to-moderate and severe Alzheimer’s disease.
The study was supported by the National Institute on Aging, the Alzheimer’s Association, an Alzheimer’s Disease Cooperative Study grant, the Alzheimer’s Disease Research Center, Jim Easton and the Sidell Kagan Foundation.
The study appears in the June 16 issue of Neurology, the medical journal of the American Academy of Neurology.
Source: University of California – Los Angeles