Nikoline Nygaard, a postdoctoral fellow in health and medical sciences at the University of Copenhagen, Copenhagen, Denmark and lead author of the study said the association “reframes the way we understand oral disease, not as something that just happens in the mouth, but as something that affects the whole body as early as childhood.”

Leveraging Registry Data

Nygaard and her team analyzed data on oral health in 568,000 children in the National Child Odontology Registry (SCOR) from 1972 through 1987 and matched it up with anonymized cardiovascular disease outcomes and demographic data from the National Patient Register and the Central Person register, respectively.

The results published in The International Journal of Cardiology showed boys with the greatest number of cavities, affecting 13-16 teeth, had a 32% higher incidence of atherosclerotic cardiovascular disease later in life compared with those with cavities in 0-4 teeth.

In girls the association was even stronger, with a 45% increase in risk linked to high numbers of dental caries (cavities and instances of tooth decay) compared with those with fewer caries. Similarly, kids with the most severe gingivitis had an increased long-term risk for cardiovascular disease — by 21% in boys and 31% in girls.

Health research in Denmark frequently draws on data in the country’s national registries, which cover the entire population, but Nygaard noted SCOR is not often used in health research.

That database contains detailed data on childhood oral health dating to 1972 with yearly registrations for each child in Denmark. Her group previously used the Danish registry to study links between childhood oral health and type 2 diabetes in adulthood.

Inflammation May Play a Role

The findings are significant and “considered a good indication that it is not a spurious association we’re dealing with,” Nygaard said.

Because the researchers used national register data, they could not directly account for lifestyle factors like smoking and dietary patterns.

“What we did instead was adjust for the highest achieved level of education on our study participants, as we know that, at least in Denmark, there is a pretty clear correlation between higher levels of education and how healthily you live,” Nygaard told Medscape Medical News. “Thus, while we did our best to factor in the effect of lifestyle, we also can’t rule out that some of the association is carried by lifestyle factors.”

The new analysis is in line with previous studies linking oral health to cardiovascular outcomes. In 2020, the World Heart Federation issued a consensus report stating there is evidence associating periodontitis with myocardial infarction and stroke.

The report authors speculated that bacteria from gum disease triggers systemic inflammation throughout the body, leading to development of atherosclerosis and cardiovascular disease.

Linking Oral and Cardiac Health

Increasing recognition of the link between oral health and cardiac health also led the American Heart Association’s Healthy Smiles, Healthy Hearts initiative to issue guidelines to help dentists identify patients with hypertension and refer them to a primary care physician for follow-up.

“Oral and systemic health should not be separated,” said Pirkko Pussinen, a professor of translational dentistry at the University of Eastern Finland in Kuopio, Finland. “Both oral infection and cardiovascular diseases are chronic in nature and both take long to develop.”

Pussinen’s group was among the first to conduct a study following oral health from childhood to adulthood. In that smaller study, Pussinen and her team found an association between childhood oral infections and subclinical carotid atherosclerosis.

Nygaard’s group is planning several follow-up studies, including one following the trajectory of oral health from childhood into adulthood.

“We can’t rule out that results in our current study are caused by oral health in childhood likely reflecting oral health in adulthood,” she said. “Beng able to account for oral health in adulthood will make it clearer whether childhood oral health in and of itself can predispose for heart disease.”

This study was funded by the Danish Dental Association and Novo Nordisk. Nygaard and Pussinen report no relevant financial relationships.

 Catherine Shaffer is a freelance science and medical writer with a background in molecular biology and pharmaceutical research. Her work has appeared extensively in scientific trade and mainstream publications and on public radio.