While memory loss is thought to be a classical first sign of Alzheimer’s disease, some middle-aged people and younger seniors may initially experience different cognitive problems such as trouble with language or problem solving, a large U.S. study suggests.

Researchers reviewed data on early symptoms for almost 8,000 Alzheimer’s patients and found one in four people under age 60 had a chief complaint unrelated to memory, though memory was by far still the most common problem overall.

“Non-memory first cognitive symptoms were more common in younger Alzheimer’s disease patients,” lead study author Josephine Barnes, a researcher at the National Hospital for Neurology and Neurosurgery in London, said by email. “Tests which explore and investigate these non-memory cognitive problems should be used so that non-memory deficits are not overlooked.”

Alzheimer’s is a brain disorder than gradually destroys memory and thinking skills and eventually leaves people unable to carry out simple tasks like dressing or eating. The disease is the most common cause of dementia among older adults, and afflicts more than 5 million Americans, according to the National Institutes of Health.

Inside the brain, Alzheimer’s is associated with abnormal clumps known as amyloid plaques and tangled bundles of fibers, often called tau or tangles. Scientists suspect that the damage begins in the hippocampus, a region of the brain involved in memory.

Barnes and colleagues reviewed neurological test results from a large U.S. database of Alzheimer’s patients to see whether the early symptoms people reported differed by age.

On average, patients were 75 years old when they first sought treatment for Alzheimer’s, though they ranged in age from 36 to 110. Most of them had mild to moderate dementia.

Among the patients who reported cognitive difficulties as their first symptoms, the proportion citing something other than memory shrank with increasing age. One in five patients in their 60s cited difficulties unrelated to memory, but this dropped to one in 10 for people in their 70s.

Because Alzheimer’s can only be definitively diagnosed after death by looking for tangles and plaque on the brain during an autopsy, this study like others exploring the disease runs the risk of including at least some patients who don’t actually have the condition, the authors acknowledge in the journal Alzheimer’s and Dementia. 

In addition, it’s possible that because the study drew patients from academic medical centers, it lured more complex cases and might not be representative of a typical Alzheimer’s patient, the authors note.

Understanding how Alzheimer’s symptoms might surface in younger patients is crucial for diagnosing them sooner and starting treatment at a point when it can do the most good, said Dr. Andrew Budson, chief of cognitive and behavioral neurology at the VA Boston Healthcare System and a neurology professor at Boston University.

The best available medicine for the disease can only turn back the clock, reversing symptoms enough to give patients the same abilities they had up to a year earlier, Budson said. 

“You can’t slow the clock down, you can just reset it,” Budson said. “It is much better to dial it back to repeat a year in your 60s than in your 80s.”


SOURCE: bit.ly/1INu4Y1 Alzheimer’s and Dementia, online April 24, 2015.

Source: Reuters