About one-third of the risk of heart attack originates in childhood

Childhood risk factors such as BMI and ‘bad’ cholesterol are associated with heart attacks and stroke in adulthood, a new study finds.

Childhood risk factors such as blood pressure, serum lipids, body mass index and smoking were both directly and indirectly associated with adult cardiovascular disease. Picture: iStock

About one-third of the risk of having a heart attack or stroke in adulthood originates in childhood, according to data from a ­pioneering 40-year study, solidifying that the most effective way to prevent cardiovascular events in middle age is to introduce interventions in childhood.

It is also clear adult cardiovascular disease (CVD) cannot be fully mitigated by risk-factor management in adulthood.

A study of more than 10,000 participants over four decades and in three countries, including Australia, showed that childhood risk factors such as blood pressure, serum lipids, body mass index and smoking were directly and indirectly associated with adult cardiovascular disease, with the largest direct effect for BMI and “bad” cholesterol.

Researchers from Australia, Finland and the US took measurements when participants were aged between three and 19, and then again after the age of 25.

“For the risk of developing CVD, childhood BMI played nearly as important a role as adulthood BMI, supporting the accumulation hypothesis,” the study, in the JAMA Network Open journal, says.

JAMA is published by the American Medical Association.

“LDL-C (total cholesterol) was important, especially in adolescence, whereas adulthood remained the most important period. The risk begins to materially accumulate in childhood, with adulthood risk factor levels having the greater impact.”

Terence Dwyer of the Murdoch Children’s Research Institute, who was involved in the Australian leg of the study over 40 years, said the findings fitted with the concept that children start to build up fatty material in coronary arteries from childhood.

“A third of the risk comes from childhood … What it means is if we truly wanted to optimally prevent cardiovascular suffering, disability and death, we should start earlier in adulthood,” he said, adding the study provided more confidence in such programs. “Now is time to say this (emphasis on childhood risk) is important.”

Professor Dwyer said once an individual had the risk factor present in childhood, they usually didn’t successfully reduce that risk factor in adulthood – even though it’s possible. “These children … had access to programs we thought were state of the art (yet) these individuals have dramatically increased risk levels.”

This could suggest the programs were not effective enough.