HealthDay News — Depression, sleep problems and behavioral changes can show up before signs of memory loss in people who go on to develop Alzheimer’s disease, a new study suggests.
Tracking more than 2,400 middle-aged people for up to seven years, the researchers found that those who developed dementia were more than twice as likely to be diagnosed with depression sooner than those without dementia.
Other behavior and mood symptoms such as apathy, anxiety, appetite changes and irritability also arrived sooner in participants who went on to cope with typical dementia symptoms, according to the research, published online in the journal Neurology.
“I wouldn’t worry at this point if you’re feeling anxious, depressed or tired that you have underlying Alzheimer’s, because in most cases it has nothing to do with an underlying Alzheimer’s process,” said study author Catherine Roe, PhD, an assistant professor of neurology at Washington University School of Medicine in St. Louis.
“We’re just trying to get a better idea of what Alzheimer’s looks like before people are even diagnosed with dementia,” Roe added. “We’re becoming more interested in symptoms occurring with Alzheimer’s, but not what people typically think of.”
Roe and her team examined data from participants aged 50 and older who had no memory or thinking problems at their first visit to one of 34 Alzheimer’s disease centers around the United States.
Over a period of up to seven years, about half remained cognitively normal, while the other half developed memory loss or thinking problems indicative of dementia.
Among the other findings, 30% of those who went on to develop dementia had depression after four years in the study, compared to 15% of participants who didn’t have dementia.
Roe noted that research hasn’t yet determined whether depression or other mood and behavioral changes result from the same underlying changes in the brain contributing to Alzheimer’s disease, or as a psychological response to dealing with the condition. And while the study showed an association between behavioral changes and Alzheimer’s risk, it did not prove a cause-and-effect link.
Roe CM, et al.“Noncognitive” symptoms of early Alzheimer’s disease. Neurology. 2015; doi: 10.1212/WNL.0000000000001238.