As part of the our Clinical Research Group, Dr Ayer studies the early-life origins of atherosclerosis. Though heart disease is often considered a disease of old age, evidence of atherosclerosis (the most common cause of heart disease) has been found in the arteries of adolescents and young adults. So Dr Ayer’s research focuses on improving the cardiovascular health of children, particularly by finding early factors that raise or lower the risk of cardiovascular disease later in life.
How can you measure the cardiovascular health of children?
“Obviously you can’t use invasive techniques in children,” says Dr Ayer. “[So] using ultrasound we measure the arterial thickness, which gives us an indication of changes that are occurring in the arterial wall. We can also use ultrasound and other non-invasive techniques to measure vascular stiffness – so the structural and functional properties of the arteries.”
A lot of Dr Ayer’s work revolves around a 14-year (and counting) study called CAPS, a study that has followed a group of children from their birth – in the late 1990s – until today. Originally an investigation into ways to mitigate childhood asthma, CAPS has now started yielding some fascinating cardiovascular research.
One important finding is that omega-3 (fish oil) supplementation from birth to age 5 can help babies with low birth weight.
Low birth weight is a risk factor for later-life cardiovascular disease, which is measurable by a thickening of the artery walls in children as young as 8.
Omega-3 in the diet stops this thickening from occurring. Interestingly, this supplementation has no beneficial effect for the average child – only for those who had low birth weight.
The CAPS study has also yielded valuable information on early-life risk factors for atherosclerosis. “We’ve looked at other determinants of [arterial] wall thickening, both the traditional risk factors like blood pressure and lipids, but also novel risk factors such as birth weight, lung function and obstructive sleep apnoea in childhood,” says Dr Ayer. Now that the children from the CAPS study are in their teenage years, Dr Ayer is investigating the effects of puberty on arterial structure and function.
When asked which CAPS study he’d like to highlight, Dr Ayer points to his study showing that smoking during pregnancy causes children to have lower HDL (“good”) cholesterol at age 8.
HDL cholesterol has a number of potentially protective actions against atherosclerosis, so smoking during pregnancy puts the child’s heart health at risk.
“It’s part of that public health message with regards to smoking and pregnancy; most people know that smoking in pregnancy is bad, but you’re building a case against it. I think that helped the case for an important public health issue.”