HaemSTAR Chair's New Year Message

Writes Richard Buka, HaemSTAR Chair

It’s been a whirlwind six months since taking over as Chair from Pip Nicolson. Leading a fluid, dynamic organisation like HaemSTAR is both a challenge and an opportunity and I’m really looking forward to 2024 and beyond.

In 2023, we added some great talent to our committee, including Olga Tsiamita, Stephen Hibbs, and Lottie Hickman. These additions make a real difference and each committee member is now driving important projects.

ISTH Legacy Funds

My highlight of 2023 has to be the awarding of nearly £30,000 from the ISTH London 2022 Legacy Fund. We’re putting this to great use with £20,000 allocated to travel grants and £10,000 for funding a HaemSTAR fellowship in collaboration with the Nigerian Society for Haematology and Blood Transfusion (NSHBT). This project is driven by Stephen Hibbs, with help from Imelda Bates, and we will be appointing two Nigerian haematology trainees as fellows in the first part of 2024 with the intention of facilitating research projects in Nigeria. We’ve also been able to invite Omalade Awodu, President of NSHBT to BSH to speak in the UK-TReN – HaemSTAR session.

Education

We’ve also introduced some educational offerings and have now hosted three webinars in collaboration with the limbic. So far, over 250 people have attended the webinars and in 2024 we will welcome talks from Suthesh Sivapalaratnam (Friday 19th January, 0830), Bernard Lämmle, Tom Bullock, Simon Stanworth and more to be confirmed. Previous talks are available on demand. Pip and I have also been recording a podcast focusing on advancements and critical appraisal in non-malignant haematology with the first episode to launch on 8th January.

Projects

Despite all these exciting projects, research and audit are our raison d’être, and we have ploughed ahead with several. The highest profile has been RAPIDO, a national audit of reversal agents for DOAC-associated bleeding. The project has over 300 collaborators entering data and has collected data on around 2,500 patient episodes including about 300 where andexanet alfa was given. Data collection closes on 5th January. We will spend a few months analysing the data and writing up with the intention of submitting an abstract to ASH 2024 with a manuscript to be submitted by the end of the summer.

Upcoming projects

I’m particularly excited about the projects coming down the pipeline. Lorna Cain, Christina Crossette-Thambiah, and Stephen Hibbs have been leading a haemoglobinopathy group that is working on, among others, a project looking at the problem of vascular access in sickle cell disease. Eman Hassan has been working on the use of tranexamic acid in anticoagulant-associated heavy menstrual bleeding, with a clinician survey recently completed and gathering 102 responses. Giulia Simini, Sajida Kazi, and Gill Swallow have been developing a project to look at the management of maternal pulmonary embolism including the use of thrombolysis and catheter-directed thrombolysis. This will start with a survey of centres to assess access to catheter-directed thrombolysis, and we will collaborate internationally with groups in Italy and the USA. This survey will come out in January 2024. Olga Tsiamita and Nick Fordham are working on an audit of neonatal thrombocytopaenia management with a data collection form now completed and ready to launch. Phil Weir and Marquita Camilleri are planning a project to look at the use of apixaban in thromboprophylaxis in myeloma. Again, this is in the later stages of planning and the team are looking for funding. Finally, we will be supporting Rupen Hargreaves with his exciting project investigating the occurrence and type of thrombosis in MPN.

Careful management of the HaemSTAR resource

I’m acutely aware that HaemSTAR collaborators are a finite resource. We cannot simply stack-up project after project, expecting people to contribute. This is why we are carefully optimising our workflow and crafting a package of projects that will appeal to different people. That said, we will always look to support creative, enthusiastic clinicians (juniors and consultants) to develop and deliver their projects. However, we are dedicated to ensuring fair recognition for each and every person who contributes to a project with a commitment to collaborative authorship.

HaemSTAR Annual Meeting – 5th February 2024

2024 is going to be a huge year for HaemSTAR and I am grateful for all your enduring support. If you are able to, please come to the HaemSTAR Annual Meeting in Birmingham on Monday 5th February 2024. Attendance is free and importantly, the meeting is tagged onto the ASH/ISTH non-malignant headlines meeting on the following day at the same venue. Whilst most delegates have to pay for this, non-consultant clinicians attending the HaemSTAR day can attend this for free by emailing sophie@hartleytaylor.co.uk once you have signed up for our day.

Blood sucking demon foetuses: women's health, evolution, and iron deficiency

Writes Dr Richard Buka,

Dr Angela Weyand is a plenary speaker for the HaemSTAR annual meeting - Feb 2024

Women’s health is going to form the focus of much of what HaemSTAR do in the coming years. For our HaemSTAR Update Day in Birmingham on 5th February 2024, we’re going to be welcoming Dr Angela Weyand as a plenary speaker - her work is discussed below.

We’re also doing some exciting projects. The first centres on the idea of giving tranexamic acid to women who are starting anticoagulation for VTE with the idea of reducing menstrual blood loss, and improving quality of life. We’re starting this with a survey.

The second project is called MaTrOn. The Maternal Audit on ThRombolysis Outcome and DecisioN will look at the use of thrombolysis for pregnant women with venous thromboembolism. Again, this will start with a survey and then we will be gathering retrospective observational data on a national scale.

Anyway, on with the blog.

Eve: How 200 years of evolution shaped the female body. Cat Bohannon

This month, I’ve been listening to a brand new audiobook that gives a unique take on human evolution. Cat Bohannon’s ‘Eve, How The Female Body Drove 200 Million Years of Human Evolution’, is a fascinating exploration of mammalian development that puts women at its centre.

It’s full of those “Oh wow!” moments and really changes your perspective. It begins with explaining how medical research is dominated by experimentation on males - male rodents are used as controlling for menstrual cycles is difficult, and makes science more expensive. She goes on to talk about the evolution of milk - did you know that egg laying mammals like the platypus don’t have nipples, with milk instead just sort of oozing from the torso. Nipples make feeding a lot more efficient.

Perhaps the most powerful idea is pinning the success of hominin species on the practice of gynaecology. She includes a whole range of practices under the gynaecology umbrella - from peer-assisted birth, to how primates seek out plants to consume that reduce fertility or induce miscarriage.

The high prevalence of iron deficiency

A renewed focus on women’s health that transcends medicine is long overdue and this is certainly true in haematology. Take iron and anaemia for example, women and girls are much more likely to suffer iron deficiency, which is poorly treated and impacts quality of life. Writing in JAMA earlier this year, Angela Weyand and colleagues found the overall prevalence of iron deficiency (ferritin <25 ng/mL) in American women and girls from age 12 to 21, was 39% and, 17% (ferritin <15 ng/mL) and 78% (ferritin <50 ng/mL. The overall prevalence of iron deficiency anaemia was 6.3% (Hb <12g/L). Iron deficiency, even without anaemia, can cause symptoms including tiredness and poor quality of life.

This got me thinking. What’s the evolutionary perspective on this? Has nature selected for iron deficiency - is this such a difficult problem to tackle?

Tonsillitis

My wife recently had a bout of tonsillitis. It left her in bed for three days with fever and horrible pain. Curiously, she’s not supposed to have any tonsils as they were removed when she was a kid. Nevertheless, when she was seen by the emergency out of hours service, strep throat was diagnosed and she was given some antibiotics. I’ve no doubt that these were necessary, and she quickly recovered.

This came out of the blue and I started thinking about how this came about. We had spent the preceding Sunday at a kids’ party in a soft-play – well known melting pots of disease. She’s otherwise a healthy 30-something, just a touch iron deficient probably because a) she’s a woman, and b) she’s had two children in the last three years and is breastfeeding the youngest. She started taking oral iron supplements again a couple of weeks before this came on.

Rates of iron deficiency around the world can be even higher than in the JAMA paper. Globally, anaemia affects 30% of women, and 40% of children rising to 60% in Africa. The vast majority of this is caused by iron deficiency. If you’re interested, there are loads of statistics on the WHO website.

Is this all nutritional? This is certainly a major causative factor. But even so, humans have evolved to thrive with scarcity of resources. It doesn’t make sense that iron deficiency should be so common unless it exerts a survival advantage in certain conditions.

Evolution and menstruation

We have evolved curious traits that, if we just think of iron deficiency as being bad, make no sense. For example, the volume of blood lost in menstruation varies widely among different species. Humans lose a lot of blood- an average about 80 ml.

This is really rare in mammals - only a handful lose this amount of blood. Most mammals simply reabsorb the material. There are a few possible explanations for this trait.

One, which has been discredited, is that this is a mechanism of cleansing the reproductive tract but there’s no evidence that more pathogens are present before or after menstruation. Another crap theory is that women synchronise periods so that all the men can get busy doing “other stuff” for that week.

“Bloodsucking demon foetuses”

In Eve, Cat Bohannon suggests that periods are a survival mechanism. Pregnancy is a stalemate between the foetus trying to hoover up as much nutrition as possible against the uterus trying to protect the mother. Building up the endometrium prior to a fertilised egg being known about is rare but evolved three times - in higher primates, elephant shrew, and some bats. The book states that “human women menstruate because it’s part of how we survive our bloodsucking demon foetuses.” By building up the endometrium prior to an egg being fertilised means that uterine defences can be dug early.

A further theory, not discussed in Eve is to do with a possible evolutionary benefit for iron deficiency. Excessive menstrual blood loss could be an adaptation to enable iron loss and maintain a state of iron deficiency, thus protection against infection.

Being able to better survive infection is often a strong driver of evolution. Many bacteria thrive on iron and the body can respond by reducing available iron which, in extended infections or inflammatory diseases leads to anaemia (anaemia of inflammation). This theory is discussed in detail in an intriguing review: Nutritional iron deficiency: an evolutionary perspective.

A good example of this is the link between intravenous iron and infection. A recent analysis showed that the number needed to treat for IV iron to lead to a 2 g/L rise in haemoglobin is 5 and to prevent transfusion was 36. Conversely, the number needed to harm – to cause infection was 62.

Plague

The drug desferrioxamine which is used as an iron chelator in people with iron overload comes from the bacterium streptomyces pilosus. The bacterium uses it to hoover up iron in its vicinity. A well known side effect of desferrioxamine treatment is sepsis caused by Yersinia enterocolitica. If you’re thinking that this infection sounds familiar, it should be - Yersinia enterocolitica is related to Yersinia pestis – the plague bacterium (and Alexandre Yersin is my favourite scientist of all time).

Yersinia enterocolitica can’t produce its own siderophore, molecules that help bacteria sequester iron. In the gut, it is able to use other bacteria’s siderophores and can cause enterocolitis. It rarely causes septicaemia except in the case of people taking desferrioxamine – as it can take-up iron bound to this in the blood stream.

A reminder of the close link between iron regulation and immunity is the HFE gene. This gene codes for a protein that influences iron absorption by modulating the expression of hepcidin. It is located on chromosome 6, close to the major histocompatibility complex (MHC) genes. Mutations in this gene cause haemochromatosis when inherited in a homozygous manner but the benefit to being a heterozygote is unclear. One might imagine that it would provide some advantage by boosting iron levels and therefore protecting against anaemia, especially in populations where dietary iron was scarce. Although this is a compelling argument, there is not much actual evidence for this; C282Y heterozygotes don’t have improved iron absorption. Another possibility is that the mutation may have in fact offered some protection against diseases including malaria through a variety of mechanisms.

Conclusion

Away from my digression into plague and haemochromatosis, I’ll come back to the main point of this piece: women’s health. We just have to accept that the way that women and girls experience and perceive the world is different to that of males. This is especially pertinent in healthcare where the experience of illness and pain is poorly studied in women. All of this needs to be viewed in the context of sexism and misogyny, both for patients and those of us that work in healthcare systems. The more we become aware of how important gender is on the way that we perceive the world, the more we can understand it, empathise, and improve lives for the better.

If you want to read more from Rich, follow his blog, Classical Compass or check out his podcast, ‘Don’t Just Read the Guidelines’ on all major platforms.