In a French cohort of patients diagnosed with multiple sclerosis (MS), no association was found between vaccination and the risk of hospitalization due to MS attacks.
Syringe with blue vaccine, vial of medicine on green background. Vector | Silphida – stock.adobe.com
“To our knowledge, this study is the most extensive investigation of the risk of MS exacerbations requiring hospitalization associated with vaccine exposure, looking at more than 36,000 exacerbations in more than 100,000 MS patients. study. Up to 11 years (mean follow-up 8.8 years),” the study’s researchers wrote.
Nested Case Crossover Analysis Published in JAMA Neurology.
Although the vaccine is said to be well suited for people with MS, there has been controversy over the possible link between vaccination and the onset of MS because infections are known to increase the risk of MS attacks. In this study, the researchers aimed to assess this association using a healthcare database of the entire French population.
The researchers collected information on 133,154 patients with at least one diagnosis of multiple sclerosis registered in the National Health Database System (SNDS) between January 1, 2007, and December 31, 2017. Restricted to patients with multiple sclerosis followed for at least 12 months. Excludes periods of 24 months or more without any records. The final patient cohort included 106,523 individuals.
An emergency episode was defined as hospitalization for at least 1 day with an overnight stay. For patients with multiple attacks, only the time between attacks was considered to identify risk and control time windows.
In addition, the researchers obtained records from the SNDS database of patients receiving vaccines at hospitals or community pharmacies. Vaccine exposure included:
- Diphtheria, tetanus, polio, whooping cough Haemophilus influenza Vaccines (DTPPHi), alone or in combination, including DTPPHi plus hepatitis B combination vaccine
- Hepatitis B virus (HBV) vaccine, excluding DTPPHi plus HBV combination vaccine
- Flu vaccine (any)
- pneumococcal vaccine
- meningococcal vaccine
- Measles, mumps, or rubella vaccine
- Other: Hepatitis A virus, tuberculosis, varicella virus, or varicella-zoster virus vaccine
In this group of patients, the mean (SD) age was 43.9 (13.8) years, and 76,471 (71.8%) were female. Of these patients, 33,864 (31.8%) had episodic MS and 72,659 (68.2%) had epidemic MS. Additionally, these patients were followed for a mean (SD) of 8.8 (3.1) years, with 35,265 (33.1%) hospitalized for an MS episode during the study follow-up period. As a result, there were 54,036 MS-related hospitalizations.
For DTPPHi, no association was found for any vaccine between hospitalization for an MS episode and vaccine exposure in the 60 days before the episode (adjusted odds ratio (aOR), 1; 95% CI, 0.92-1.09) (aOR , 0.95; 95% CI, 0.82-1.11), influenza vaccine (aOR, 0.98; 95% CI, 0.88-1.09), and pneumococcal vaccine (aOR, 1.20; 95% CI, 0.94-1.55).
However, the researchers acknowledged some limitations to the study, including the use of a database that only included hospital diagnoses and medication dispensations, and a limited definition of MS episodes, defining only those that resulted in hospitalization and were associated with a specific MS diagnosis. disease.
Despite these limitations, the researchers believe that the study failed to show that there is no associated risk between vaccination and the onset of multiple sclerosis, and believe that more studies should be conducted to evaluate this association between other vaccine subtypes to confirm these findings.
“Regardless of the age groups studied, we did not observe an association between the risk of hospitalization due to MS attacks and vaccination, either overall or considered individually,” the researchers wrote. “Since health insurance in France is Being universal and with essentially unlimited access to care, we believe this study identified nearly all hospitalizations occurring among all people with MS in France (67 million patients registered) over 11 years.”
refer to
Grimaldi L, Papeix C, Hamon Y, et al. Vaccines and the risk of hospitalization for multiple sclerosis attacks. JAMA Neurol. 2023;80(10):1098–1104. doi:10.1001/jamaneurol.2023.2968