Pertussis Carries Epilepsy Risk

Childhood pertussis carries an increased risk of developing epilepsy, Danish researchers report.

Pertussis (whooping cough) sickens tens of thousands of children in the US annually, according to the US Centers for Disease Control and Prevention. The highest case total in recent years was 48,277 reported cases in 2012. Though inoculation against pertussis is common, the illness occurred in 5,563 US children under age 7 who were vaccinated, the CDC reported.

Pertussis is known to cause encephalopathy and seizures in infants. However, the risk of childhood epilepsy following pertussis is unknown.

In an article in JAMA, Danish researchers Morten Olsen, MD, PhD, and colleagues report on the longer term consequences for children in Denmark who contracted the illness. The team found that these children are at increased risk of epilepsy, compared to the general population.

The researchers studied 4,700 pediatric patients with pertussis of whom 90 developed epilepsy.

Compared to the general population, patients who had come down with pertussis were 1.7 times more likely to develop epilepsy than those who did not. The incidence of epilepsy in children who had pertussis was 1.56 cases per 1,000 person years compared to .88 cases per 1,000 person years in children who did not have pertussis.

“However, the absolute risk was low,” they concluded.

The researchers looked population-based medical registries covering all Danish hospitals to identify a cohort of all patients with pertussis born between 1978 and 2011