Congenital heart defect rates may be much higher than once thought

A broad new analysis of Colorado insurance data suggests national estimates may be severely undercounting children born with heart defects, and at least half of them have other genetic disorders and chronic conditions.

The study, published Monday in the American Heart Association journal Circulation: Cardiovascular Quality and Outcomes, offers the first U.S. population-level analysis of congenital heart defects, or CHDs. Researchers say the much-needed data can be used to better plan for the treatment of children who may need lifelong care.

"Seismic advancements in medical care and surgical treatments have significantly increased the survival of children born with congenital heart disease," said Dr. Devin Parker, a postdoctoral fellow in the department of social epidemiology at Sorbonne Université in Paris and the study's lead author. "A comprehensive assessment of the CHD health burden can support appropriate allocation of resources for diagnosis, care coordination, care access and cost-effective treatment strategies."

Congenital heart defects are the most common birth defect in the U.S., with previous estimates placing the number at about 40,000 babies each year, or 1% of all births nationally. Advances in medical care and treatment have allowed children born with heart defects to live longer, but those who do are at higher risk for neurodevelopmental problems, cancer, depression, asthma, obesity, high blood pressure, stroke, heart failure and rheumatologic disease.

Measuring how many children are affected by heart defects has been challenging, said Dr. Michael O'Byrne, a pediatric cardiologist at the Children's Hospital of Philadelphia, who wrote an editorial accompanying the study. Prior estimates came from birth defect registries, which failed to include cases that were not causing symptoms and treated early in life.

The fractured U.S. health insurance system, involving multiple commercial and public payers, also made it difficult to accurately capture data about children with heart defects, he said.

In the new study, researchers analyzed all-payer claims data from 2012 to 2019 for children in Colorado who were 18 or younger on Jan. 1, 2012. All-payer claims databases include all public and private insurance claims for health care services within a state. Colorado is one of 21 states that had such databases at the time the study was conducted, though the number continues to grow.

From more than 1.5 million children in the Colorado database, Parker and her team identified 30,512 who were diagnosed with heart defects – nearly 2%.

Children with Down syndrome and other chromosomal abnormalities often associated with heart defects have typically been excluded from heart defect research but were included in the new study. Among children diagnosed with a heart defect, 10% also had at least one genetic disorder.

More than half of the children with heart defects also had one or more complex chronic health conditions, including respiratory, metabolic, gastrointestinal, neurologic and neuromuscular disorders. And more than a third received at least one disability diagnosis over the eight-year study period.

"Our prevalence study is distinctly unique from previous studies because we applied the entire range of congenital heart disease diagnoses relevant for children across all eligible care facilities," Parker said. "We hypothesized that we would find a higher prevalence, but the results were still surprising."

She also was surprised "to learn that so many disorders and disabilities are experienced by children over time. It was very eye-opening."

Though the analysis looked only at Colorado claims data, it is substantially more representative than prior studies estimating heart defect rates, Parker said.

"Previous studies were even more geographically confined, using data for just a single metropolitan city or single health center," she said. Because this study included the state's entire pediatric population and broader diagnostic codes, "we can broadly generalize that there are more children diagnosed with CHD than previously thought."

While the analysis pointed to a higher-than-expected prevalence, that doesn't mean congenital heart defects are increasing, Parker said. "It could possibly be related to improved detection or diagnosis after infancy."

Some heart defects are obvious early in life, while others require diagnosis with an echocardiogram or other diagnostic tools that were not used broadly when previous estimates were calculated, O'Byrne said. "Now, we're screening with prenatal ultrasounds and we're finding less obvious heart defects. There's also more access to cardiologists and echocardiography across the entire life span, which likely catches less clinically significant disease. But the importance to society … isn't any smaller. They will still need to be treated later in life."

Getting a more accurate picture of how many children may be living with heart defects and associated health issues is critical, O'Byrne said.

"The resources that help people with disease are always finite," he said. "We have to make choices about how we allocate philanthropy, government resources and research dollars, and that should be guided by how frequently people are affected by disease. This shows the number of people affected by CHD is larger than we thought."