The Alzheimer's Association notes that 5.3 million people have Alzheimer's disease, a degenerative disorder that affects cognition. As the disease progresses, patients lose more of their functions, such as memory, language and judgment. For example, in the early stage of Alzheimer's disease, patients have trouble finding the correct name for an object. By the advanced stage, the language problem worsens to a point that patients cannot understand language anymore.
MedlinePlus points out that before patients develop Alzheimer's disease, they can have another condition that affects cognitive function: mild cognitive impairment (MCI). If a person has MCI, she may or may not develop Alzheimer's disease. With MCI, patients have some problems with different cognitive functions. For example, patients may take a longer time to do more complicated activities, such as those involving calculations. Multitasking may be affected: patients may find it more difficult than before to do more than one task at a time. Patients with MCI can have difficulty solving problems. Memory is also affected by MCI. Patients can have problems remembering recent events or conversations.
A new study published in Neurology notes that testing cognition and performing a brain scan on MCI patients may predict if they develop Alzheimer's disease later in their lives. The study included 85 people who were in the Alzheimer's Disease Neuroimaging Initiative. The researchers followed these people for 1.9 years, recording their cognitive data. All of the participants had MCI, but no other neurological disease. The ages of the participants ranged from 55 to 90.
The researchers used different Alzheimer's assessments to test cognitive skills and any changes to the brain. For example, the researchers gave participants an episodic memory test, in which they read participants a list of words and asked them to repeat it. With the brain scans, the researchers used an MRI scan to measure the size of the hippocampus, the part of the brain that converts short-term memories into long-term memories, and a PET scan to check for metabolic irregularities. The researchers also tallied levels of beta-amyloid, the protein accumulation found in Alzheimer's disease patients' brains, and did a genetic analysis for the type of APOE gene that participants had.
The researchers pointed out in the study that none of the participants reverted to their pre-MCI state. Instead, 28 participants developed AD. The researchers found that the PET scan and the episodic memory tests were effective in predicting whether Alzheimer's disease would occur. HealthDay News reports that having an abnormal result on these tests makes a person 12 times more likely to develop Alzheimer's disease. However, there is a downside to this study. While these tests helped in the prediction of Alzheimer's disease, PET scans are expensive and not everyone would be able to afford it, according to HealthDay News.