Researchers working at UCLA have published a new study in which they suggest that people with memory problems who are depressed are more likely to develop Alzheimer’s disease than others. They did also found however that the widely used Alzheimer’s drug donepezil may be useful in helping to delay the progression of the disease in those individuals with mild cognitive impairment or memory difficulties.

Mild cognitive impairment is defined as the stage between the cognitive decline that comes naturally with aging and Alzheimer’s disease. These people experience memory problems that are usually greater than might be expected with normal aging but do not show any other symptoms of Alzheimer’s such as a difficulty in completing basic daily tasks.

Over the course of three years 756 people between the ages of 55 and 91 who had been diagnosed as having mild cognitive impairment  were followed and monitored by the researchers. Out of the study’s total participants 208 were also diagnosed as depressed , using a standard test that measures the severity and intensity of depression in an individual. For each single point increase on the test researchers found that the participants risk for developing full blown Alzheimer’s disease went up by 3 percent.

“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 and a member of the UCLA Mary S. Easton Center for Alzheimer’s Disease Research. “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.”

Study participants were divided into three groups. They were either then given donepezil, a Vitamin E supplement or a harmless placebo pill. Amongst the depressed participants in the group that was taking the donepezil 11 percent developed Alzheimer’s at 1.7 years in comparison to the 25 percent of those taking either the vitamin E or the placebo pill.

When accessed at 2.2 years 14 perecent of the depressed donepezil group had been diagnosed with the disease while the figure was 29 percent in the other groups. For those who had not been diagnosed as depressed at the start of the study, donepezil seemed to have little effect.

The drug has yet to be approved by the FDA for treating mild cognitive impairment. It is currently indicated only for use in Alzheimer’s patients with mild to moderate and severe disease.

However the researchers were buoyed by their findings “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.