Association of autistic spectrum disorder and the measles, mumps, and rubella vaccine – A systematic review of current epidemiological evidence

Abstract

The authors conducted a systematic review of the evidence for and against the existence of an association between autistic spectrum disorder and the measles, mumps and rubella (MMR) vaccine. Specifically, they tested four hypotheses: (1) that the rates of autistic spectrum disorder is higher in individuals who have received MMR than those who did not, (2) that an increase in autistic spectrum disorder may be occurring as a result of MMR, (3) that the development of autistic spectrum disorder is temporally associated with receiving the MMR, and (4) that a new variant form of autistic spectrum disorder may be associated with the MMR vaccine. The authors sought to identify all controlled epidemiological articles examining for an association between autistic spectrum disorder and the MMR vaccine. They extracted data from the articles on the characteristics and objectives of the study as well as evidence of an association.Twelve articles met the inclusion criteria. One study found no difference in the rates of autistic spectrum disorder and the MMR vaccine in children who were vaccinated and those who were not. Six studies examined for evidence of an increase in autistic spectrum disorder associated with an increase in the MMR vaccine coverage; none of the six showed evidence of an association. Four studies examined if a variant form of autistic spectrum disorder was associated with the MMR vaccine; none of the four showed evidence of an association. Eight studies attempted to determine if there was a temporal association between developing autistic spectrum disorder and receiving the MMR vaccine. Of these, one study identified an increase in parental concern in the 6‐month period following vaccination with MMR in one of its analyses. The results of all other studies showed no association between autistic spectrum disorder and the MMR vaccine. The authors concluded that the current literature does not suggest an association between autistic spectrum disorder and the MMR vaccine. The authors did note that the studies were not large enough even in aggregate to rule out a link between a rare variant form of autistic spectrum disorder and the MMR vaccine; they held, however, that given the real risks of not vaccinating and that the risks and existence of variant autistic spectrum disorder remain theoretical, current policies should continue to advocate the use of the MMR vaccine.