Important discussions at the Alzheimer’s Association International Conference 2014
The Alzheimer’s Association International Conference 2014 provides the perfect platform for dementia researchers to discuss some of the more controversial, thought-provoking and fascinating issues facing dementia research. We summarised three of these for you:
1. Should we screen the general population for dementia?
While early diagnosis of dementia is a government priority, we do not screen the healthy population in the UK for dementia. There are often discussions in the press and within the research community about whether new advances in detection techniques could allow the general population testing for diseases like Alzheimer’s.
Today we heard a lively debate about the pros and cons of population screening. Dr Bruno Dubois at Salpâtrière University Hospital in Paris argued that more and more people are worried about their memory and that over 95% of people they surveyed would want to know if they had dementia.
However, Prof Carol Brayne from the University of Cambridge stressed that population screening requires simple, cheap, reliable, sensitive and well-validated diagnostic tests. We would need to know exactly who to give these tests to and what the results mean. Sadly, such tests are not available for dementia, and the underlying causes are so complex that general population screening would likely give incorrect diagnoses to as many people as it correctly identified.
Prof Brayne said that ‘we have not done enough robust work to be confident about certainty in screening, in terms of the patients in front of us.’ So while it’s clear that good progress is being made in detecting early changes in diseases like Alzheimer’s, more discussions are needed about how and when these tests should be used and whether the benefits of using these outweigh the risks of ‘harming the healthy’ through misdiagnosis. A really interesting and important discussion that is likely to intensify in the coming years.
Do leave us a comment and give us your views on this debate.
2. Are dementia rates falling?
We blogged about this after last year’s AAIC meeting, when researchers suggested falling dementia rates in the UK. Today, Dr Kenneth Langa of the University of Michigan discussed similar evidence from Rotterdam and Denmark, suggesting individual risk of dementia is falling in higher income countries. Possible explanations included better treatment of cardiovascular risk factors and increasing education. However he warned that rising obesity and diabetes could buck this trend – diabetes rates worldwide has doubled since 1980. Read more about these studies on our news pages.
However, we also heard that the world population of over 65s is growing and in the next few years, for the first time in human history, the population of over 65s will outnumber children under the age of five. For that reason, it’s expected that numbers of people affected by dementia will rise to mean that 16% of the global population will have the condition in 2050.
A large proportion of these cases will be in low and middle income countries. In contrast to falling risk in higher income countries, lower middle income countries are facing rising trends in dementia. This outlines just how important it is to study and understand trends in dementia risk so that lessons can be learnt and passed on.
3. How can the population of Iceland teach the rest of the world about genetics?
We heard a fascinating and thought-provoking talk from Dr Kári Stefánsson, cofounder of deCODE Genetics in Iceland. Because the population of Iceland was founded by a small number of individuals, there is less genetic variation than in other larger and more mixed populations. This means that it’s much easier to detect risk genes in this group of people, providing vital clues to the disease that are relevant to everyone.
Genetic studies in Iceland, where more than 65% of the population have provided DNA samples for research, are contributing huge amounts to our understanding of the genetic risk of Alzheimer’s. In 2012, the team discovered a rare mutation in the Icelandic population that strongly protected against Alzheimer’s. This genetic change was in the gene that makes the amyloid protein, supporting an often controversial research debate about the importance of amyloid in Alzheimer’s. The conference committee deemed this research finding to have had the biggest impact in the dementia research field over the past year.
Interestingly Dr Stefánsson also told the conference that they had discovered changes in the DNA code of individuals that could underpin behaviours such as likelihood to smoke and even the inclination to do crosswords. He said it was ‘extraordinarily difficult to separate lifestyle and genetics for complex diseases like Alzheimer’s’, as our genetics may underpin a large amount of how we interact with, and respond to, our environment.
Lots of interesting questions raised and it’s important to see these discussions taking place between researchers all across the world. To help bring answers to these questions sooner, you can donate to our Defeat Dementia campaign.