Lack of association between measles-mumps-rubella vaccination and autism in children: a case-control study.
OBJECTIVE
The first objective of the study was to determine whether there is a relationship between the measles-mumps-rubella (MMR) vaccination and autism in children. The second objective was to examine whether the risk of autism differs between use of MMR and the single measles vaccine.


METHODS
Case-control study.


METHODS
The 96 cases with childhood or atypical autism, aged 2 to 15, were included into the study group. Controls consisted of 192 children individually matched to cases by year of birth, sex, and general practitioners.


METHODS
Data on autism diagnosis and vaccination history were from physicians. Data on the other probable autism risk factors were collected from mothers. Logistic conditional regression was used to assess the risk of autism resulting from vaccination. Assessment was made for children vaccinated (1) Before diagnosis of autism, and (2) Before first symptoms of autism onset. Odds ratios were adjusted to mother's age, medication during pregnancy, gestation time, perinatal injury and Apgar score.


RESULTS
For children vaccinated before diagnosis, autism risk was lower in children vaccinated with MMR than in the nonvaccinated (OR: 0.17, 95% CI: 0.06-0.52) as well as to vaccinated with single measles vaccine (OR: 0.44, 95% CI: 0.22-0.91). The risk for vaccinated versus nonvaccinated (independent of vaccine type) was 0.28 (95% CI: 0.10-0.76). The risk connected with being vaccinated before onset of first symptoms was significantly lower only for MMR versus single vaccine (OR: 0.47, 95% CI: 0.22-0.99).


CONCLUSIONS
The study provides evidence against the association of autism with either MMR or a single measles vaccine.
Mrozek-Budzyn
Dorota
D
Department of Epidemiology and Preventive Medicine, Jagiellonian University, Collegium Medicum, Krakow, Poland. dorotamrozek@tlen.pl
Kiełtyka
Agnieszka
A
Majewska
Renata
R
D000293:Adolescent; D000328:Adult; D001321:Autistic Disorder / Q000139:chemically induced*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008457:Measles / Q000517:prevention & control; D022542:Measles-Mumps-Rubella Vaccine / Q000009:adverse effects*; D009107:Mumps / Q000517:prevention & control; D011247:Pregnancy; D012409:Rubella / Q000517:prevention & control; D014611:Vaccination / Q000009:adverse effects*
D022542:Measles-Mumps-Rubella Vaccine