Vaccines do not contribute to multiple sclerosis or other central nervous system demyelinating syndrome onset, according to a study published in JAMA Neurology.
Vaccines are not associated with multiple sclerosis (MS), suggests a study published in JAMA Neurology.
Researchers from Kaiser Permanente in California studied patients in order to determine if vaccines, such as hepatitis B (hepB) and human papillomavirus (HPV), increase the risk of MS or other central nervous system demyelinating syndromes (CNS ADS).
Health records of patients were collected between 2008 and 2011, which included medical reviews from MS specialists. The researchers matched 5 controls per MS case based on age, sex, and zip code.
Investigators identified 780 cases of MS or CNS ADS and 3,885; of those, 92 cases and 459 were female patients aged 9 to 26 years, or the suggested administration age group for the HPV vaccine.
Exposure to vaccinations was marked in the patients’ electronic vaccinations records system.
The researchers found no correlation between hepB, HPV, or any vaccination and the risk of CNS ADS up to 3 years. However, in younger — less than 50 years – patients, vaccination of any type saw an association with an increased risk of CNS ADS onset within the first 30 days after vaccination. The researchers note that this onset may be an acceleration of symptoms in patients who already have MS or CNS ADS diseases, but had not yet at that point experienced any related symptoms.
“Our data do not support a causal link between current vaccines and the risk of MS or other CNS ADS,” Annette Langer-Gould, MD, PhD, and the other authors conclude. “Our findings do not warrant any change in vaccine policy.”
The authors note the results for the HPV vaccinations are inconclusive because the small number of cases, and the limited literature on the topic thus far.
Previously, literature suggested HPV and hepB vaccines damaged the inner layer of the nerve cells, or myelin, which is a key factor in accelerating MS. Other studies show mixed results, though most show vaccines have no effect.