Recent Advances in Dementia Diagnosis and Treatment
September is World Alzheimer’s Month and Alzheimer Chapters all over the world are focusing on efforts to raise awareness about this devastating disease that robs its victims of their memories and other mental faculties. Although 115 years have passed since the first case of Alzheimer’s was described by Dr. Alois Alzheimer, a cure has eluded us, despite intensive research efforts in the leading nations of the world. Nevertheless, these efforts have expanded our knowledge of this disease and brought us closer to a cure.
Currently, there are 43,000 Albertans living with a diagnosis of dementia. It has been projected to double by 2031, due to population aging, in the absence of a disease-modifying agent.
This has serious social and financial implications, in addition to the inevitable personal consequences for the impacted families.
Dementia refers to progressive decline in mental abilities that is sufficiently severe to impact daily life. It is characterized by loss of recent memory, impaired reasoning and decision-making, visual perception difficulties, communication difficulties, and changes in mood, personality and behaviour.
There are several causes for dementia, the most common being Alzheimer’s disease. Here abnormal clusters of protein called amyloid plaques and tau tangles cause nerve cells to die and the brain to shrink, slowly and silently, over several years. These changes do not show up in X-ray or CT scan, making early diagnosis almost impossible at present.
The medications currently available for symptom control, such as Aricept, Exelon, and Reminyl work only in the early stage. Therefore, many Alzheimer’s patients fail to benefit from these medications.
The search for a curative or a disease-modifying drug and methods to facilitate early diagnosis have been ongoing. In the wake of World Alzheimer’s Awareness Month, research community has reported remarkable advances in both areas.
Researchers from Arizona State University claim to have developed a blood test that is able to identify people with early Alzheimer’s among a group that also consisted of healthy people and those with Parkinson’s.
The Banner research team made use of the fact that in Alzheimer’s, numerous genes involved in inflammation and cellular stress are activated. A simple blood test which analyzes the amounts of various messenger RNAs — the intermediate molecule between a gene and its encoded protein — could be enough to spot them, they figured.
The test easily distinguished between people with and without a family history, but its ability to predict who among those with a family history that would develop disease was somewhat lower. It could also spot people with the Alzheimer’s risk gene APOE4 who had not developed dementia, when compared to APOE4carrier with early Alzheimer’s and people without the risk gene.
Almost simultaneously researchers from United Kingdom also reported their success in developing a blood test. They used Vibrational Spectroscopy, a technique that can analyze a range of different molecules in a biological fluid, such as blood plasma.
Experiments showed that the test could identify Alzheimer’s patients, and rule out Alzheimer’s , with 70 percent accuracy. When researchers added information about the risk gene APOE4, the test performed with 86% accuracy.
Scientists at McGill’s flagship mental health research center, the Douglas Mental Health University Institutes Translational Neuroimaging Laboratory, used artificial intelligence techniques and big data to develop an algorithm that can, with a single amyloid PET scan, detect dementia signatures in the brains of patients at risk of developing Alzheimer’s disease two years before symptoms.
The researchers propose a machine learning-based predictive method designed to assess the progression to dementia within a 24-month period, based on regional information obtained from a single amyloid positron emission tomography (PET) scan. The investigators’ novel algorithm demonstrated an accuracy rate of 84 percent, outperforming the existing algorithms using the same biomarker measures.
As for treatment to cure or slow the progression of Alzheimer’s, Biogen Pharma reports that their anti-amyloid antibody, Aducanumab reduced deposits of the amyloid plaque associated with Alzheimer’s disease in the brains of early-stage patients who took part in a three-year extension trial.
The amyloid levels of patients treated for 36 months fell below the cut-off for a scan indicating Alzheimer’s, researchers reported. In addition, symptom assessments suggested that patients continued to benefit in their second and third years of treatment.
These exciting advancements serve to infuse new energy and enthusiasm in the research community, while providing us with hope and optimism to face the coming years.
Padmaja Genesh, who holds a bachelor degree in medicine and surgery as well as a bachelor degree in Gerontology, has spent several years teaching and working with health care agencies. A past resident of Red Deer, and a past board member of Red Deer Golden Circle, she is now a Learning Specialist at the Alzheimer Society of Calgary. Please send your comments to padmajaganeshy@yahoo.ca