The last few weeks have seen a steady increase in pictures and videos in the press and social media of people having ice poured over themselves. Even your editors at FTD talk have undergone the challenge (video). These charitable efforts for the MND association in the UK and ALS association in the US are aiming to raise awareness and money for the disorder called amyotrophic lateral sclerosis (ALS) or motor neurone disease (MND). This is a progressive illness causing weakness in the muscles of the body, often affecting the muscles in the arms, legs or those that control speech or swallowing initially. Why is it important for people with FTD to know about this?
We have known about the overlap between FTD and MND for many years but it is only in recent times that we have started to understand this more. Firstly, from a symptom point of view we know that people with FTD can develop the symptoms of MND during the course of their illness (see our factsheet here) and vice versa. Secondly, from a genetics point of view we know that people who have a mutation in the C9ORF72 gene can develop FTD on its own, MND on its own or both conditions together. Lastly, when we look at the brain and nerve cells of people with FTD or MND we commonly see the presence of an abnormal protein called TDP-43 in both conditions. This overlap in the symptoms, genetics and pathology of FTD and MND links these two disorders together and has led to much greater collaboration between doctors and scientists to find out more.
What do research studies tell us about how common the overlap is from a symptom point of view? Studies seem to suggest that around 15% of people who present with symptoms of FTD initially will develop MND at some point during the illness. For people who present with symptoms of MND initially the numbers are less clear – this is partly because some people with MND may develop mild problems with their thinking or behaviour but not develop the full set of symptoms that we would call FTD. In a large study from Phukan and colleagues in Ireland, 14% of people with MND also had symptoms of FTD but a further 34% had problems with their thinking – in other words nearly half of people with MND had some form of cognitive impairment.
The finding of mutations in the C9ORF72 gene in 2011 as a major cause of both FTD and MND has really increased our knowledge of both disorders. People with FTD due to a C9ORF72 mutation are much more likely to have MND than those without a mutation. Similarly, people with MND due to a C9ORF72 mutation are more likely to develop FTD than those without. By studying why people with C9ORF72 mutations develop symptoms we have learned much more about both disorders and it may be that these studies will lead to drugs that can work for both FTD and MND.
The Ice Bucket Challenge is therefore important not only for raising awareness and money for MND but it will also help to do the same for FTD, and hopefully lead us to learn more about both disorders. Remember that you can donate to the MND association in the UK by texting ICED55 £5 to 70070, and to the ALS association in the US here.
Phukan J, Elamin M, Bede P, Jordan N, Gallagher L, Byrne S, Lynch C, Pender N, Hardiman O. The syndrome of cognitive impairment in amyotrophic lateral sclerosis: a population-based study. J Neurol Neurosurg Psychiatry. 2012;83(1):102-8.