According to the researchers, the most commonly used methods for investigating early signs of Alzheimer’s disease in the Swedish public healthcare system include a variety of cognitive memory tests and computed tomography. For the past few years, it has also been possible to perform an analysis of a cerebrospinal fluid sample, which boosts the chances of early detection. Thus far, only patients in memory clinics have been offered the test, the researchers said in an article in Drug Discovery & Development.
Recently, a method called amyloid PET was approved for clinical use in Sweden. Clinicians administer a special substance that binds to a protein in the brain, beta-amyloid, to the patient. This substance is used as a marker for Alzheimer’s changes, which are subsequently mapped with PET imaging. There have been differences of opinions about whether cerebrospinal fluid samples or PET imaging would be the best methodology for detecting early-stage Alzheimer’s disease.
According to Sebastian Palmqvist, MD, PhD, at Lund University, “In the study, both the cerebrospinal fluid sample and the amyloid PET scans were able to identify approximately 90 per cent of the patients who would be diagnosed with Alzheimer’s later on. Our conclusion is therefore that the two methods work equally well to achieve this aim. One can thus choose the method on the basis of cost, expertise or patient preference.”
The Swedish researchers believe that both methods are also good at identifying which individuals are healthy and unlikely to develop Alzheimer’s disease within the next ten years. Nonetheless, when the diagnosis is reached without reference to a cerebrospinal fluid sample or amyloid PET imaging, its accuracy can drop to 60 to 70 percent, they said. Late detection of Alzheimer’s disease impacts today’s healthcare, as well as the development of future treatments.
“Previous drug trials to evaluate new treatments for the presence of amyloid in Alzheimer’s cases failed, partly because treatment began too late in the course of the disease. With two accurate tools for early diagnosis, we can identify suitable participants at an early stage of Alzheimer’s disease. This will considerably increase the chances of being able to prove a positive effect for new drugs”, concludes Oskar Hansson, associate professor and neurologist at Lund University.