PARIS – Vaccines may trigger relapses in patients with neuromyelitis optica spectrum disorder (NMOSD), but that risk is diminished if patients are on immunosuppressive therapy, researchers reported here.
In a retrospective review of data from three centers, the rate of vaccine-associated relapses within 30, 60, and 90 days was significantly higher than the likelihood of a relapse spontaneously occurring during that time if NMOSD patients weren’t on immunotherapy, Maureen Mealy, RN, of Johns Hopkins University in Baltimore, and colleagues reported in a poster presented at the ECTRIMS-ACTRIMS meeting.
“We found that patients who are on immunotherapy who received a vaccine fared the best and had the fewest relapses, supporting the idea that NMOSD patients should be on immunotherapy,” Mealy told MedPage Today.
Activation of the immune system from infections has been shown to increase the risk of relapse in MS. But vaccines have not been shown to be associated with demyelinating or inflammatory events in MS. The cases reported in the MS literature linked with vaccination tended to affect the optic nerves or spinal cord, raising the concern that patients with NMOSD may be more susceptible, Mealy said.
She and colleagues conducted a retrospective chart review of 90 NMOSD patients from three centers: Johns Hopkins, Charite Hospital in Berlin, and a neurology clinic in Medellin, Colombia. They assessed NMOSD relapses that occurred 30, 60, or 90 days after vaccinations, including influenza, Tdap, hepatitis, and pneumococcal vaccines. Patients had a total of 211 vaccinations and experienced 340 relapses over a median disease course of 6.6 years.
They saw that seven patients relapsed within 30 days of vaccination, six relapsed between 31-60 days, and four relapsed between 61-90 days — thus, a total of 17 out of the 90 patients included.
The rate of vaccine-associated relapses within 30, 60, and 90 days was significantly higher than the likelihood of a relapse spontaneously occurring within each of the given time frames only among patients with NMOSD who were not on preventive immunotherapy, Mealy reported.
Among patients with NMOSD who were on immunotherapy to prevent relapses, there was no significant increase in risk of relapse associated with vaccines, she said.
Mealy cautioned that her study looked only at inactivated vaccines, as live vaccines are contraindicated in this population and in patients with MS. Still, she concluded that the study suggests a risk of vaccination-associated relapses among untreated NMOSD patients, but being on immunosuppressive therapy at the time of vaccination aborts the risk.
Jay Rosenberg, MD, of the Neurology Center of Southern California in San Diego, who wasn’t involved in the research, said the study “shows there may be a problem post-vaccination, that must be a trigger in the appropriate genetic patient.”
The problem, he said, is that “you don’t know who is going to respond that way.”
Mealy noted that she’s currently working on a prospective analysis of the effects of vaccination on NMOSD patients being seen at her center at Johns Hopkins.
Mealy disclosed no financial relationships with industry.