Whooping cough may be tied to a slightly increased risk for a young child to develop epilepsy, a new study finds.
Whooping cough (pertussis) is relatively rare in the United States, however. And the absolute risk to any one child of getting epilepsy remains "low", said Dr Meghan Fleming, a neurologist at Lenox Hill Hospital in New York City.
Read: Whooping cough code cracked
She reviewed the findings from the new study.
Disease still occurs
According to background information in the study, vaccination can prevent whooping cough, but roughly 16 million cases of the disease still occur worldwide each year.
There were nearly 50,000 whooping cough cases reported in the United States in 2012, the study authors noted.
Read: Persistent cough in kids can often be whooping cough
In the new study, a team led by Dr Morten Olsen of Aarhus University Hospital in Denmark looked at 4,700 Danish children with whooping cough.
The children in the study were born between 1978 and 2011 and were followed until the end of 2011.
More than half (53 percent) had been diagnosed with the respiratory infection before they were 6 months old.
Each of the children with whooping cough was compared against 10 age- and gender-matched children in the general population.
Read: Newborns get whooping cough from siblings
While the study couldn't prove cause-and-effect, Olsen's team reported that by age 10, epilepsy was diagnosed in 1.7 percent of children in the whooping cough group and 0.9 percent of those in the general population.
Lack of oxygen
The age at which the child had contracted whooping cough seemed to matter.
Children older than 3 years old when they were diagnosed with whooping cough were no more likely to develop epilepsy than those in the general population, the study found.
Whooping cough can cause coughing spasms and is associated with seizures in infants, but a link between whooping cough and epilepsy has been unknown, the researchers said.
So what might connect the respiratory ailment and epilepsy?
Read: Whooping cough making a comeback
The researchers suggested that brain damage caused by lack of oxygen during coughing fits may be one reason for the possible association.
According to Fleming, "Future studies may wish to investigate the underlying immune-linked mechanisms triggered by infections which influence the development of epilepsy."
The study was published in the Journal of the American Medical Association.
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