Bringing together several strands - influence and lifelong impact

An introduction to Professor David Barker, an obstetrician and epidemiologist - and a gentle and thoughtful man - gave shape to what Dr Simon Chapman had maybe known but been unable to define: why he ended up in medicine. Simon introduces our #ChoosePaediatrics theme of the month: the influence and lifelong impact of paediatrics.
Rope tied in a knot

We all have people in our clinical lives who inspire and influence us. For me, the first was (the now late) Professor David Barker, obstetrician and epidemiologist.

I was a student when we met. He had already established his hypothesis of fetal and infant origins of adult disease. Over the months that I knew him, I was captivated by his idea that maternal nutrition and the environment could set in train small metabolic changes in the unborn infant that could lead to adult disease. His eureka moment had come from studying standardised mortality ratios in the UK from the first decade of the 20th century. He had noticed how areas of high infant mortality in 1900 closely matched those of high mortality from ischaemic heart disease some seventy years later. Could whatever had influenced the deaths of those infants, he reasoned, have affected those that survived, making them susceptible to heart disease later on?

By serendipity better described elsewhere1 , he came across a detailed ledger documenting the birth weights of babies born in Hertfordshire between 1911 and 1939 (not widespread practice at the time), all measured by a community midwife and health visitor team, overseen by a remarkable figure, Ethel Margaret Burnside. Professor Barker followed up all the babies, now known as the Hertfordshire cohort. He digitised the handwritten records, tracking down each person and, where necessary, linking them with information from death certificates.

Following all this work the answer was clear: the babies with the lowest weights grew to be adults with the highest risk of cardiac disease. The implication was that maternal, and perhaps infant, nutrition might hold an important key to the prevention of adult disease.

...what led me to paediatrics: the idea that small changes in small people can lead to huge changes by the time they are grown

The Barker Hypothesis, as it came to be known, has been on a journey since that time in the early noughties, and I am not going to follow the thread of where those ideas have led, because that is not what Professor Barker's legacy has been for me - that is something far more personal. Instead it gave shape to what I had maybe known but been unable to define until then - why it was I had ended up, in my meandering and hapless way, in medicine.

This gentle and thoughtful man had brought together for me several strands of a thread of my own. One strand was that understanding the mechanism of things can lead to simple but powerful solutions - like better nutrition, sanitation or immunisation for all - to big problems. It is arguably interventions like these that have had far more impact on children's health in the history of paediatrics than any of the medicine or surgery.

Another strand is that curiosity is infectious. There is at once delight and satisfaction in finding patterns and meaning in the familiar, like suddenly seeing the image in the colours of those magic eye drawings that was there all along. And if you can see it, others will see it, too.

And, another strand was what led me to paediatrics: the idea that small changes in small people can lead to huge changes by the time they are grown. This particularly stays with me on the ward rounds and the clinics even today, now that the babies I met as an SHO have grown into adults; knowing that each encounter, if I get it right, can have repercussions which echo across a person's life and might lead them to be healthier and happier. At least, that is always my hope.

#ChoosePaediatrics - find out more

Dr Simon Chapman is a paediatrician specialising in eating disorders, diabetes and endocrinology - find him on Twitter @eatyourpeas

  • 1Barker, D. The midwife, the coincidence, and the hypothesis. BMJ. 2003; 327(7429): 1428–143