Wednesday, June 19, 2024


“You may choose to look the other way, but you can never say again that you did not know.”

— William Wilberforce


Autism Prevalence is Declining in California Counties With Higher Incomes

boy resting his head on table

Story Highlights

  • Researchers have documented that the prevalence of autism spectrum disorder (ASD) is declining in financially secure, predominantly Caucasian communities in California, in contrast to steeply rising rates seen in counties where many families of every race are living in poverty.
  • Researchers did not determine whether the observed declines are related to accessibility of health services, decreased reliance on department of Department of Developmental Services or variations in lifestyle choices.
  • Some of the life choices that might affect ASD risk and may be more available to families with higher incomes include healthier diets, earlier and more concentrated health care interventions, lower exposure to environmental toxins and chronic stress; and use of fewer vaccines, as “vaccine hesitancy” is also more common among this demographic.

Higher income, primarily Caucasian communities in California were once considered to have a greater number of children with autism spectrum disorders (ASD).1 The differences in prevalence of ASD among different communities were often attributed to socioeconomic factors influenced by adequate or inadequate access to healthcare services, which impacted evaluation, diagnosis and treatment of ASD.2 A recent study out of California shows that autism rates are declining among Caucasian families with higher incomes, while prevalence of ASD among those families of all races living in poverty are increasing.

Details Provide New Insight Into ASD Prevalence

Using data from California’s Department of Developmental Services (DDS), the researchers looked at children born between 1993 and 2013 in the 36 most populous counties in California. They found that, while rates of ASD continued to climb among all children with birth years up until 2000, the numbers subsequently diverged, flattening or decreasing among Caucasians living in communities with higher incomes and continuing to climb among both Caucasians and Hispanics living in poorer counties.

In most of California’s counties, ASD incidence in Asian children began as comparable to or lower than that for Caucasians in birth year 1993 but was comparable to or higher than that for Caucasians by birth year 2013. For the minority of African American children, insufficient data were available for most counties.

Where prevalence could be assessed, ASD rates were higher than for Caucasians in five counties, comparable to Caucasians in two other areas and slightly lower than for Caucasians in Los Angeles.3 For African Americans in California overall, the ASD incidence rate of 1.8 percent is in keeping with other data showing that autism is increasing markedly among African Americans.4

Breaking down the data by county provided details about the decelerating but still continuing rise in incidence of ASD among Caucasians in California. The study showed that, rather than a decelerating increase among Caucasians as a whole, there appear to be steep increases in lower income counties contrasting with declines in higher income counties. The authors concluded that starting in about 2000, Caucasian parents with higher incomes were either opting for private services in lieu of DDS or were making environmental exposure and lifestyle changes that lowered their children’s risk for ASD.

The study authors have proposed several possible scenarios. They suggest that higher income and education may be associated with better prenatal and postnatal practices, as well as improved birth outcomes that might lower the risk of ASD. Parents with higher incomes also may have access to early and proactive interventions that either change the diagnosis or decrease the severity of ASD, which could make their children ineligible for involvement with DDS, a state social service that tends to focus on the most severely affected children. The researchers also speculated about whether families with higher incomes are relying on behavioral health services available through private insurance or channels, while poorer families must rely on DDS.

Lead researcher Cynthia Nevison said, “While autism was once considered a condition that occurs mainly among whites of high socioeconomic status, these data suggest that the brunt of severe autism is now increasingly being borne by low-income families and ethnic minorities.”

Lifestyle Choices May Contribute

Other lifestyle choices that can limit immune inflammation and oxidative stress, both strong markers associated with ASD, include healthy dietary choices, avoidance of environmental toxins, and reduction of chronic stress, all of which may be more accessible to the wealthy.

Another factor common to the same demographic of parents—Caucasian, well educated, and financially secure—is the tendency to question vaccine safety and effectiveness, described by some as “vaccine hesitancy.” Though not mentioned by the researchers of this particular study, parents who question vaccination also “tend to be better educated.” A recently published study looking at communities in Texas found that parents who are “college-educated, live in suburban or urban areas, have higher median incomes and are ethnically white are less likely to vaccinate their children.”5

The authors of the California study concluded that further study is needed to determine whether their findings will hold true in other areas of the country.


1 Beck M. Autism Rates Higher Among Certain Immigrants, Minorities. The Wall Street Journal June 23, 2014.
2 Spotlight On: Racial and Ethnic Differences in Children Identified with Autism Spectrum Disorder (ASD). National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention Aug. 27, 2019.
3 Nevison C, Parker W. California Autism Prevalence by County and Race/Ethnicity: Declining Trends Among Wealthy Whites. Journal of Autism and Developmental Disorders Mar. 19, 2020.,
4 Marshall L. Autism Rates Declining Among Wealthy Whites, Escalating Among Poor. Medical Express Mar. 20, 2020.
5 Demographics Linked to Choice Not to Vaccinate Children in Texas, Study Finds. UT News Mar. 10, 2020.

14 Responses

  1. How about the impact of Obamacare which then exposed people of lower socio-economic brackets to increased pediatric care? Now, the poor get as much pediatric vaccinations as the wealthier did before many started to become aware and resist.

    1. It says right in the article the inflection point is the year 2000. You’re barking up the wrong tree.

  2. One other factor may well be that very low income parents find a financial incentive to have their child labeled “disabled,” as they then get more money and can also get more individualized education within the public school system.

    Not such a happy outcome when their child may then be required to take psychiatric drugs.

  3. They forgot to mention that DDS / Regional Centers refuse services to a great majority of school aged children with ASD diagnosis – under pretense that the school districts are responsible for those services, and to young adults with ASD – under pretense that “they are not scientifically shown to help”.
    Every Regional Center has “client advocacy” service – why though? They were created to serve clients, were they not? And when I called those advocates a few years back, they were too busy to take on new clients. So those MFs at Regional Centers are receiving enormous amount of taxpayer funds under pretense of “serving the developmentally disabled”, while in reality not a single child or young adult with autism that I know is receiving ANY services form that so called public agency.
    California Latterman Act shall be dissolved and money should be paid directly to the families of State abhorrent vaccination policies victims.

  4. Clearly you have a data-subset that would be very valuable in establishing vaccine safety rates. If you correlate ASD to this group and simply ask whether the children have received vaccines I’m sure you’ll find what the science already tells us – because I am a California member of the group you describe. No amount of suppression of facts has deterred us from being “vaccine hesitant” and because we are highly educated, the cheap “fake news” approach to presenting facts on the internet doesn’t work on us. We already know the answer to this question, “What’s causing this population subset to experience better ASD outcomes.” We also know that if you include that in your study, just has a Harvard Group discovered, your paper will not be published and you’ll be uninvited to conferences.

  5. While I appreciate this article, the headline “Autism Prevalence is Declining in California Counties With Higher Incomes” misrepresents the journal article by Nevison that it is based on. The headline’s statement is not necessarily true and cannot be confirmed directly from the California Department of Developmental Services (CDDS) numbers.

    As this article said, the Nevison article indicates there are multiple possible explanations for the observed CDDS data. One of these is that higher income families may be opting out of working with the CDDS.

    As it happens, a team (Pearl et al) at the California Department of Public Health did a study recently that showed that the apparent decrease in birth year ASD case counts in the CDDS data among whites was limited to those who had private health insurance.

    We can certainly speculate about what might be causing some of the observed data. It would be very exciting to learn that better health practices caused reduced autism prevalence. Any specific hypotheses about that are just speculation at right now; we don’t know yet.

    Alternatively, it might be true that some families simply decided it’s not worth the trouble to become CDDS clients, because the benefits are so limited and they insist you work with private insurance if you have it. State law mandates insurance coverage for certain autism treatments.

    Maybe both hypotheses, maybe something else. We just don’t know yet.

  6. MOST IMPORTANT: These data were obtained prior to SB 276/ 277 laws. So we absolutely need to have a comparision trial once mandatory vaccination was implemented. So glad to see this study as the pre-mandataory vaccination autism rates needed to be established and broken down. (Since we will likley never get a vaccinated vs unvaccinated study done )

  7. No government or medical industry has the right to play God by forcing vaccination on anyone or anything! This is past insanity when the medical industry has a monopoly on vaccination, so they have made it mandatory for school children. So what has happen is school children have become their cash cow! Now isn’t that wonderful….how could we let this happen? Well, because corruption is running in every department of the government and medical industry! There is NO pandemic! Let me repeat myself, there is NO pandemic! The only thing that will come out of all this BS is all your rights are taken away. What little rights we had left! Wake the hell up and do not comply to the governments demands of social distancing etc, You are being corralled like cattle!

    1. “There is no pandemic”…please leave. Just go away. Your insanity makes all of us look bad. You are a drag on the cause.

  8. How about a study of the vaccine children to the un-vaccined children.

    Big pharm won’t do it!

    No one would ever allow another shot!

  9. It is interesting with the controversy of vaccines they (the researchers) did not ask if the children were vaccinated or not.

Leave a Reply

Your email address will not be published. Required fields are marked *

Search in Archive