There's a tremendous amount of research literature that does not make it into public consumption. Coupling this lack of trickle down with a voracious need to feel certainty where none may exist, many parents faced with an autism diagnosis will gravitate towards those individuals who offer the certainty they are seeking. They find this certainty, these assurances, not with mainstream medicine or psychology, but with alternative medicine and snake oil salesman who offer guarantees that cannot be delivered on.

That's okay, though, most of the time, for the con men plying unsuspecting and dedicated parents. Throw in a clause that if it doesn't work (as one RNA supplement provider does), the parent must not have faithfully given the supplements exactly as prescribed. These charlatans have a keen understanding of how to keep the clients roped in, the sunk ship fallacy, guilt, self-justification, affect heuristic all combine to make certain that if the woo-seller gets them roped in initially, they are bound to stay. If they do manage to recognize they've been had, they're more likely to quietly slip away than to proclaim it at the top of their lungs.

One of the big selling points the anti-vaccine parents insist on is that they had perfectly normal developing children and within a magical six hour window everything is changed. Their child disappears before their eyes, loses all skills, and is diagnosed with autism. We know that vaccine reactions do occur, sometimes serious ones. It's an insult to parents who truly have undergone this to co-opt this story. And it does appear to be an unintentional co-option on the part of some of these parents. Hey, some parents who blame vaccines don't even go over the story, talk about it; they just say they know it's the vaccines.They had a perfectly normal child, they had vaccines, the child was later diagnosed with autism. Kid not vaccinated? No problem. Maternal mercury load did it. Or wait, change the story and insist all the kids are vaccinated.

Dachel claims thousands of diapered non-verbal teenagers who were perfect at two. I thought, as I have the time, that I'd go through the latest autism research and look to see if we're getting any better at identifying true autistic regression and the proportion of children diagnosed with autism who were developmentally on target and then suddenly regressed.

Wiggens et al. (2009) note that "questions regarding the number of children with an ASD who experience regression, the mean age at which regression occurs, and whether developmental delays exist prior to the loss of skills remain unanswered" (p. 360). To try to get to some answers, Wiggens et al."analyzed data from a comprehensive, population-based surveillance program at the Centers for Disease Control and Prevention (CDC)that systematically gathers and records behavioral and diagnostic information on children who display characteristics associated with ASDs" (p. 360).

For their study, Wiggens et al. looked at MADDSP ASD surveillance records: "Of the 285 children who met ASD surveillance case status, 49 (17%) had developmental regression documented in surveillance records. Of the children who met the ASD case status and had a previously documented ASD,26 percent had documented developmental regression. Forty-four of the children who met ASD surveillance case status and had document regression were boys, yielding a male:female ratio of 8.8:1.0.Age at time of regression was available for 45 participants.The mean age at time of regression was 28.2 months(median 24.0 months; mode 24.0months), although there was considerable variation about the mean (SD 18.9 months; range 1–91 months)" (p. 364).

When they compared these two groups (regression version nonregression), here's what they found:

Children with an ASD with documented regression showed significantly more general developmental concerns at or before 36 months of age than did children with an ASD without documented regression...than children with an ASD without a documented loss of skills"(p. 365).
In addition, "Children with an ASD with documented regression were also significantly more likely than those without documented regression to have cognitive impairment" (p. 365). Of those with documented regression, 29 percent scored "average or above average cognitive skills" while 38 percent of those who did not undergo regression scored average or above. Wiggens et al. note that "children with an ASD with documented regression were rated by clinician reviewers as being more impaired than children with an ASDwithout a documented loss of skills" (p. 366).

The question of cognitive impairment and levels of functionality come up alot on the blogs, forums, and various threads. In this study, which looked at population data: "Of the 268 children who had cognitive test data available in surveillance records, 40 percent scored in the range of cognitive impairment (IQ ≤ 70), and 60 percent were not cognitively impaired. Fifty percent of children in the sample were rated by clinician reviewers as moderately impaired, 29 percent were rated as mildly impaired, and 21 percent were rated as severely impaired" (p. 364).

Contrary to certain individuals insistence that the rate of cognitive impairment is 80 percent or so, this study which actually looked at the data gathered by the "Metropolitan Atlanta Developmental Disabilities Surveillance Program (MADDSP) at the CDC" found a rate of 40 percent. And they only found 21 percent being severely impaired, also contrary to what AoAers would have you believe.

In their discussion, Wiggens et al. write:

Using a population-based surveillance cohort, we found that the percentage of children with autistic regression ranged from 17 percent among children who met ASD surveillance definitions, to 26 percent among children who met ASD surveillance definitions and had recognized ASD documented in surveillance records. Our estimates are in line with those from previous studies (Rutter and Lord, 1987; Siperstein and Volkmar, 2004)and suggest that autistic regression is more likely to be noted when a child has a clearly documented ASD diagnosis. This pattern may explain why higher prevalence rates for autistic regression are found in studies that use clinically referred samples (Davidovitch et al., 2000) and implies that any loss of social or language skills is an important ‘red flag’ for ASDs (Filipek et al., 2000).

Furthermore, children in our sample who experienced autistic regression were more likely to have cognitive impairment and were rated as significantly more impaired by clinician reviewers.These results, coupled with the finding that the male:female ratio increases more than 50 percent in autistic regression (Bernabei et al., 2007), lend credence to the idea that autistic regression is related to severity of disability and is much more likely to occur in boys than in girls (p. 369).
The folks at AoA sell this wholesale idea of children who were developmentally fine, perfect, etc, with no problems prior to vaccination and then bam! the vaccines change it all. Without looking at potential causation, just at the data collected, Wiggens et al. found that even in these cases of documented regression, that "Almost half of the children with autistic regression in our sample were noted to have developmental concerns prior to the loss of skills, which supports previous research using clinical interview data" (p. 369).

The subpopulation of regressive autism is an important one to examine, but it is highly unlikely that vaccines will be borne out as the responsible agent. And with almost half of the cases exhibiting developmental concerns, there's an inherent call to skepticism here.

What needs to be examined is the potentiality of seizure activity in these children, which could account for a loss of skills: "Seizures or seizure-like behaviors have been associated with autistic regression in some children (Tuchman and Rapin, 1997).We found that children in our sample with documented regression were significantly more likely than those without documented regression to experience seizures or seizure-like behaviors. Moreover, seizures or seizure-like behaviors were specifically noted to occur before the loss of skills in 8 percent of records with documented autistic regression.

These findings corroborate retrospective parental reports that identify seizure activity as a trigger for loss of skills (Goldberg et al., 2003; Shinnar et al., 2001). These findings also highlight the need for future clinical research that examines the relationship between seizures and subclinical seizure activity and autistic regression" (p. 371).

References:

Wiggins, L., Rice, C.,&Baio, J. (2009). Developmental regression in children with an autism spectrum disorder identified by a population-based surveillance system. Autism: The International Journal of Research&Practice, 13(4), 357-374. doi:10.1177/1362361309105662.