The MND 'type'?

A question that has piqued my curiosity for some time is whether we can say anything about the 'type' of people who get MND.  'Type' could include elements of people's personality, but it could be any traits that are more likely to be associated with people that have MND than those who don't develop the disease. Given that about 90% of cases of MND seem to arise spontaneously in the population (that is there is no family history of the disease), then it would be extremely helpful for early diagnosis and possibly intervention if we knew which people would be most likely to go on and develop MND.

Of course, this would never be an exact science, and we have to be cautious about looking for easy patterns.  If learning about MND teaches us anything it is that there are likely a huge variety of reasons why someone develops this disease.  Those could be any combination of genetic background, developmental, environmental, or lifestyle factors, and likely the interaction of all of them over time.  We can't afford to narrow our view to exclude people that don't conform to a stereotype, but equally, a rigorous understanding of type might give us some predictive power, an insight into the mechanism of the disease, or a better grasp of which treatments might bring benefit.

So if there is a 'type' of person that is more likely to develop MND, what kinds of ways could we approach learning about that?

We have the epidemiological data: 1-2 people in every 100,000 will develop MND in any year, and the average age of onset is 57 years.  Slightly more men than women develop ALS, but the proportions even out in older patients.  There seem to be some populations where MND occurs more frequently than we would expect, and one well-known example is in top division Italian football players.  But building up a more insightful picture is really difficult because MND is rare, and so requires big populations to be confident that any increased incidence is not just due to chance, or because of some specific but unusual reason.

This information feels frustratingly crude.

More recently, we are starting to build up a picture of the kinds of things people with MND are exposed to in their lives.  In one US study, MND was more frequently associated with people who had exposures to fertilisers and pesticides, and this has been found - although not consistently - in other studies as well.  Questionnaire-based methods have shown that MND sufferers have higher levels of work and leisure physical activity, and Dutch researchers recently found that increased leisure time physical activity was correlated with an increased risk of MND.  The hypothesis is not that the physical activity causes MND, but that the type of people that favour physical activity are also the people that are more likely to go on and develop the illness.

These are some tantalising clues.

We have the experiences of people who work closely with MND sufferers.  Physicians see hundreds of patients with MND, and some will speculate - with due caveats - about the traits they feel they see more often.  The archetype is someone slim who has led an active life - a 'go-er and do-er', and had little illness to date.  I was really struck by a paragraph that echoes this in the excellent and moving memoir - Rowing Without Oars - by Ulla-Carin Lindquist:

"Who is your typical patient?" I ask Nurse Margaretha.
Her reply comes straightway: "Well-educated, highly intelligent, with great integrity.  Seldom overweight or careless with themselves.  Often sporty.  Eighty per cent of my patients are what one usually calls type-A individuals.  They are high achievers with integrity who make huge demands on themselves."

I recognise all of those features in my mum.  Which is not to say it's true - this is the MND type - but it is interesting.

But it seems to me we need to go much deeper.  We know people come in different shapes and sizes, with different personalities and dispositions.  What we don't understand is how those features relate to illness and wellbeing.  I wonder if there are traditions, other than the Western medical tradition, that are more comfortable with 'typing' people.  I'm thinking of systems such as Ayurveda and Traditional Chinese Medicine.  It might seem a bit far-fetched, but I'm going to investigate.  I'll let you know what I find out!