A new JAMA Network Open study suggests that nearly one third of adults in a Swedish cohort who contracted bacterial meningitis as children have permanent neurologic disabilities as a result.
Scientists from Merck and the Karolinska Instituet in Stockholm led the study. They analyzed data from 3,623 adults who had bacterial meningitis before they were 18 years old from 1987 to 2021 and 32,607 matched uninfected controls. There was a median age at meningitis diagnosis of 1.5 years, with 44.2% women and 55.8% men. In addition, median follow-up was at 23.7 years.
The participants who had bacterial meningitis as children had “a higher rate of all seven studied neurologic disabilities, and nearly one-third (29.0%) had at least one such disability, compared with one-tenth of controls.” Among the highest absolute risk of disabilities were behavioral and emotional disorders, hearing loss, and impaired vision. The greatest adjusted hazard ratios (aHRs), which is a measurement of the ratio of occurrence in the group with meningitis versus the control group, were for structural head injuries (26.0), hearing loss (7.90), and motor function disorders (4.55). In addition, “the aHRs for cognitive disabilities, seizures, hearing loss, and motor function disorders were significantly higher for people infected with S pneumoniae…compared with Haemophilus influenzae and Neisseria meningitidis.”
Children who contracted bacterial meningitis at a younger age than the median age were also more likely to develop cognitive disabilities, seizures, behavioral and emotional disorders, and intracranial structural injuries than those who were diagnosed at an older age than the median. To that effect, the researchers wrote that “the damage to the brain and nervous system that can follow an episode of bacterial meningitis is more detrimental for young children who are at a sensitive stage in their physical and mental development.”
The study also found that the risk of disabilities was “highest in the first 3 years after diagnosis but remained elevated at 5 years postdiagnosis.” The authors noted that “the young age at diagnosis in this study…imposes clinical difficulties on detection of disabilities after an episode of bacterial meningitis, which could explain why there was no significantly elevated risk of behavioral and emotional disorders during the first 1 to 3 years of follow-up (these disabilities are difficult to detect at an early age).”
The authors emphasized “the need to educate parents on the benefits of pneumococcal vaccination and to promote the importance of clinical vigilance in detecting disabilities…among pediatric bacterial meningitis survivors.” Study coauthor Federico Iovino, PhD, of the Karolinska Institutet’s neuroscience department, mentions that he and his colleagues are “researching how to protect neurons during the time it takes for antibiotics to cross the blood-brain barrier.”
CIDRAP has the news release.
