Physicians rely upon an array of sophisticated tests to diagnose their patients, but new research indicates a simple, inexpensive and non-invasive test may help doctors catch Alzheimer’s early in the disease’s progression.
A study funded by the National Institute on Aging and presented at the Alzheimer’s Association International Conference (AAIC) in July showed how a simple scratch-and-sniff test called the University of Pennsylvania Smell Identification Test (UPSIT) can help predict memory decline. Alzheimer’s is the most common type of dementia, causing problems with memory, thinking and behavior.
Researchers tested 84 elderly adults who had either mild cognitive impairment or normal memory and followed up with them after six months. Researcher found participants who were able to identify fewer than 35 of the 40 odors on the UPSIT test were more than three times as likely to show memory decline when doctors followed up with them after at least six months than participants with a higher UPSIT score.
“This type of testing would be an excellent way of helping with diagnosing a condition such as dementia,” says Dr. Ty Brown, a neurologist with St. Elizabeth Physicians. “At this point, the testing that helps diagnose the condition is either very long (neuropsychological testing), expensive (PET scan), or invasive (lumbar puncture). While not perfect, the preliminary results appear to show that the UPSIT was just as effective as PET or lumbar puncture in diagnosing memory loss.”
Although odor identification impairment is an early sign of Alzheimer’s disease, a smell test alone isn’t enough to diagnose Alzheimer’s. That’s because the test would falsely diagnose a lot of people including smokers, those with respiratory infections, and those who suffer from other odor-impairing conditions, such as Parkinson’s disease and Lewy body dementia. Still, Dr. Brown says, it could play an important role in diagnosing patients sooner.
“The advantage to this testing is it could be performed in the office quickly and easily,” he says. That could lead to earlier detection, earlier treatment and possibly delaying the need for interventions such as nursing home placement.
Although researchers must still focus on better medications to treat dementia, Dr. Brown says the UPSIT test “is an example of a very promising diagnostic tool.”
