I have been unwavering on this one point – there is no link between the MMR vaccine and autism spectrum disorder (ASD). They are simply unrelated, based on high quality evidence published in respected peer-reviewed journals across the world. To dispute this conclusion, using only low quality evidence published in predatory and low impact factor journals, is the epitome of science denialism.
There are some interesting early results from a study, published in Nature, that is examining brain development in infants who are at risk for autism spectrum disorder. The study hasn’t uncovered any new information about what may cause autism, but it did confirm that the MMR vaccine is unrelated to autism. Throw this study onto the mountain of evidence that completely debunks that myth.
The ongoing study’s results indicates that changes in the brain in early infancy may be predictive of an autism diagnosis at age 2 in children who have higher odds of autism because an older sibling has been diagnosed with ASD. The researchers took MRI images of the brains of children at higher risk at ages 6, 12, and 24 months, along with administering a test at age 24 months that assists in the diagnosis of autism along with another test that evaluates social skills.
The early results (the final paper will come out within a year or two) suggests that rapid growth of the surface of the cerebrum from ages 6-12 months preceded an increase in brain volume at age 12-24 months in children at risk for ASD and who were diagnosed with ASD at 24 months. Based on this cortical surface growth, the researchers were able to predict an ASD diagnosis in 81% of high risk children who eventually were diagnosed with ASD.
Again, this study didn’t provide us with any information about possible causality for ASD – it provides us some evidence of predictive diagnostic methods. Moreover, the study had a relatively low study population, and we really need repeated studies to confirm the value of this study.
Emily Willingham, writing in Forbes, does a rather thorough review of the study for those interested in the predictive ability of the study. She says this about what this study says about any relationship between the MMR vaccine and an ASD diagnosis:
Finally, these changes before age 12 months that are associated with a later autism diagnosis precede the timing of administration of the MMR vaccine. This vaccine, readers may recall, is the one that true-believer anti-vaccine activists consistently promote as causative in autism. According to the vaccination schedule, it is administered at age 12 months. These latest detected changes arise before that age, but the rapid growth associated with them kicks in right at about age 12 months, once again illustrating that coincidence of events doesn’t always mean their association.
Dr. Willingham states that the changes that precede a diagnosis of autism appear well before the first administration of the vaccine. The first MMR vaccination just happens to be coincidental to the rapid growth that is associated with ASD. Remember correlation doesn’t imply causation, especially now that we have evidence that the brain changes indicated in ASD occur prior to administration of the MMR vaccine.
I know that the “true-believer anti-vaccine activists” will be unconvinced by this evidence, and that is sad. There is simply no evidence that MMR vaccine and autism are related. In fact, evidence suggest that they are not related.
The MMR vaccine saves lives, so let’s just protect our children with it.
- Hazlett HC, Gu H, Munsell BC, Kim SH, Styner M, Wolff JJ, Elison JT, Swanson MR, Zhu H, Botteron KN, Collins DL, Constantino JN, Dager SR, Estes AM, Evans AC, Fonov VS, Gerig G, Kostopoulos P, McKinstry RC, Pandey J, Paterson S, Pruett JR, Schultz RT, Shaw DW, Zwaigenbaum L, Piven J; IBIS Network.; Clinical Sites.; Data Coordinating Center.; Image Processing Core.; Statistical Analysis.. Early brain development in infants at high risk for autism spectrum disorder. Nature. 2017 Feb 15;542(7641):348-351. doi: 10.1038/nature21369. PubMed PMID: 28202961.