Currently more than 55 million adults live with dementia worldwide, and there are nearly 10 million new cases every year. As most countries have an ageing population, this number is expected to rise to 78 million in 2030 and 139 million in 2050. Professor Catriona McLean has over 25 years’ experience in brain banking and is the diagnostic neuropathologist for all the cases referred to the Victorian Brain Bank for diagnosis and research. She explains why it is essential that Australia increases its neuropathology capacity to better understand dementia.
“Dementia is the second leading cause of death in Australia and is the leading cause of death for Australian women. As a society, I believe we need to look everywhere we can to try and treat dementia. It is still interesting that the only way to get an accurate diagnosis is to get to the end stage and study the brain post-mortem. What is largely concerning is that it is not an effectively treatable disorder and what we are left with is years and years of disability in the patient.
“There are many different types of dementia, all of which ultimately may require different treatments. Currently, the only way we can diagnose a lot of those different types with 100% confidence is through neuropathological analysis and there are not many people in Australia now who can do that. We really need to build up our capacity in Australia to meet this continual increase in dementia as it is going to become a huge problem.
“There is an important period coming up which will see a significant increase in adult-onset dementia cases as the worlds’ population ages. We need to do what we can as pathologists to work with our colleagues to do translational work with clinical studies, treatment options, imaging options, and diagnostic procedures during life so we can get a better understanding of this area,” said Prof McLean.
Dementia is the term used to describe the symptoms of a large group of illnesses which cause a progressive decline in a person’s cognitive functioning. It is a broad term used to describe a loss of memory, intellect, rationality, social skills, and physical functioning. It is more common in people over the age of 65, but in some cases, it can also affect people in their 30s, 40s, or 50s.
There are over 30 diseases which may cause dementia. Alzheimer's disease is the most common form and may contribute to 60-70% of cases. Other major forms include vascular dementia, dementia with Lewy bodies, and a group of diseases that contribute to frontotemporal dementia (degeneration of the frontal lobe of the brain). There are additional, more rare subtypes which also include genetic, infective and toxic causes.
“As we learn more about this area, we have realised that there are different types of dementia. For example, dementia of extreme old age may not necessarily be Alzheimer’s disease - it could be a different dementia pattern which looks different down the microscope. This wouldn’t be known unless we get careful neuropathological analysis of these cases. If it is assumed everyone has the same disease clinically then we will never get an understanding of this disease process.
“We simply don’t have really effective, highly accurate in-life diagnostic methods. There are scans that can be performed, and analysis of Cerebrospinal fluid (CSF) which are improving the diagnostic specificity during life, but it is still not 100%. It is getting more and more critical to analyse the brain which is why we are trying hard to maintain an Australian Brain bank network. We are hopeful that we will be able to get a grant to look at how new treatment options are leading to changes in the brain pathology and trying to translate what that actually means and whether it is being effective,” said Prof McLean.
