Hospitalized preterm infants who received routine 2-month vaccines were 2.7 times more likely to experience brief apneic events than those who were not vaccinated, according to a study published today in JAMA Pediatrics (https://bit.ly/4h4956t). Study authors and AAP experts, however, said the benefits of vaccination outweigh the risk of apnea, and the results do not warrant changes to immunization recommendations for preterm infants.
“Unvaccinated premature infants face much higher risks of developing preventable respiratory illnesses and infection than any risks posed by apneic events related to vaccination,” said Eric. C. Eichenwald, M.D., FAAP, chairman of the AAP Committee on Fetus and Newborn. “The protection vaccinations offer these infants can be life-saving, while apnea episodes are brief and monitored in the hospital.”
Previous studies found that apnea may be associated with vaccination of preterm infants. The findings are among the reasons that many preterm infants are undervaccinated, despite recommendations from the Advisory Committee on Immunization Practices and the AAP that most preterm infants should receive all recommended vaccines at the same chronological age as term infants.
Researchers conducted a randomized study of 223 preterm infants at three U.S. neonatal intensive care units to assess the risk of apnea after receiving the 13-valent pneumococcal conjugate vaccine, diphtheria and tetanus toxoids and acellular pertussis vaccine, hepatitis B vaccine, inactivated poliovirus vaccine and Haemophilus influenzae type b vaccine.
All of the infants were born at less than 33 weeks’ gestational age and were 6-12 weeks postnatal age. Forty-eight percent were vaccinated and 52% were not.
The infants were monitored for 48 hours after vaccination. One or more apnea events were observed in 23% of the vaccinated group and 10% of the unvaccinated group.
“(T)he episodes of apnea after vaccination in our study of hospitalized premature infants were brief and without serious complications,” lead author Rachel G. Greenberg, M.D., FAAP, said in a news release.
Apneic events were defined as a pause in respiration for longer than 20 seconds or a pause of longer than 15 seconds with associated bradycardia of less than 80 beats per minute. The mean duration of apneic episodes did not differ significantly between the vaccinated (27.7 seconds) and unvaccinated (32.3 seconds) groups, the study found.
“We encourage neonatal clinicians to continue to provide evidence-based anticipatory guidance about post-vaccination apnea risk,” the authors concluded.