Why Are Autism Rates Steadily Rising?

Stefania Sterling with her son Charlie, who was diagnosed at age 3 with autism.
Stefania Sterling was just 21 when she had her son, Charlie. She was young and healthy, with no genetic issues apparent in either her or her husband's family, so she expected Charlie to be typical.
"It is surprising that the prevalence of a significant disorder like autism has risen so consistently over a relatively brief period."
It wasn't until she went to a Mommy and Me music class when he was one, and she saw all the other one-year-olds walking, that she realized how different her son was. He could barely crawl, didn't speak, and made no eye contact. By the time he was three, he was diagnosed as being on the lower functioning end of the autism spectrum.
She isn't sure why it happened – and researchers, too, are still trying to understand the basis of the complex condition. Studies suggest that genes can act together with influences from the environment to affect development in ways that lead to Autism Spectrum Disorder (ASD). But rates of ASD are rising dramatically, making the need to figure out why it's happening all the more urgent.
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Indeed, the CDC's latest autism report, released last week, which uses 2016 data, found that the prevalence of ASD in four-year-old children was one in 64 children, or 15.6 affected children per 1,000. That's more than the 14.1 rate they found in 2014, for the 11 states included in the study. New Jersey, as in years past, was the highest, with 25.3 per 1,000, compared to Missouri, which had just 8.8 per 1,000.
The rate for eight-year-olds had risen as well. Researchers found the ASD prevalence nationwide was 18.5 per 1,000, or one in 54, about 10 percent higher than the 16.8 rate found in 2014. New Jersey, again, was the highest, at one in 32 kids, compared to Colorado, which had the lowest rate, at one in 76 kids. For New Jersey, that's a 175 percent rise from the baseline number taken in 2000, when the state had just one in 101 kids.
"It is surprising that the prevalence of a significant disorder like autism has risen so consistently over a relatively brief period," said Walter Zahorodny, an associate professor of pediatrics at Rutgers New Jersey Medical School, who was involved in collecting the data.
The study echoed the findings of a surprising 2011 study in South Korea that found 1 in every 38 students had ASD. That was the the first comprehensive study of autism prevalence using a total population sample: A team of investigators from the U.S., South Korea, and Canada looked at 55,000 children ages 7 to 12 living in a community in South Korea and found that 2.64 percent of them had some level of autism.
Searching for Answers
Scientists can't put their finger on why rates are rising. Some say it's better diagnosis. That is, it's not that more people have autism. It's that we're better at detecting it. Others attribute it to changes in the diagnostic criteria. Specifically, the May 2013 update of the Diagnostic and Statistical Manual of Mental Disorders-5 -- the standard classification of mental disorders -- removed the communication deficit from the autism definition, which made more children fall under that category. Cynical observers believe physicians and therapists are handing out the diagnosis more freely to allow access to services available only to children with autism, but that are also effective for other children.
Alycia Halladay, chief science officer for the Autism Science Foundation in New York, said she wishes there were just one answer, but there's not. While she believes the rising ASD numbers are due in part to factors like better diagnosis and a change in the definition, she does not believe that accounts for the entire rise in prevalence. As for the high numbers in New Jersey, she said the state has always had a higher prevalence of autism compared to other states. It is also one of the few states that does a good job at recording cases of autism in its educational records, meaning that children in New Jersey are more likely to be counted compared to kids in other states.
"Not every state is as good as New Jersey," she said. "That accounts for some of the difference compared to elsewhere, but we don't know if it's all of the difference in prevalence, or most of it, or what."
"What we do know is that vaccinations do not cause autism."
There is simply no defined proven reason for these increases, said Scott Badesch, outgoing president and CEO of the Autism Society of America.
"There are suggestions that it is based on better diagnosis, but there are also suggestions that the incidence of autism is in fact increasing due to reasons that have yet been determined," he said, adding, "What we do know is that vaccinations do not cause autism."
Zahorodny, the pediatrics professor, believes something is going on beyond better detection or evolving definitions.
"Changes in awareness and shifts in how children are identified or diagnosed are relevant, but they only take you so far in accounting for an increase of this magnitude," he said. "We don't know what is driving the surge in autism recorded by the ADDM Network and others."
He suggested that the increase in prevalence could be due to non-genetic environmental triggers or risk factors we do not yet know about, citing possibilities including parental age, prematurity, low birth rate, multiplicity, breech presentation, or C-section delivery. It may not be one, but rather several factors combined, he said.
"Increases in ASD prevalence have affected the whole population, so the triggers or risks must be very widely dispersed across all strata," he added.
There are studies that find new risk factors for ASD almost on a daily basis, said Idan Menashe, assistant professor in the Department of Health at Ben-Gurion University of the Negev, the fastest growing research university in Israel.
"There are plenty of studies that find new genetic variants (and new genes)," he said. In addition, various prenatal and perinatal risk factors are associated with a risk of ASD. He cited a study his university conducted last year on the relationship between C-section births and ASD, which found that exposure to general anesthesia may explain the association.
Whatever the cause, health practitioners are seeing the consequences in real time.
"People say rates are higher because of the changes in the diagnostic criteria," said Dr. Roseann Capanna-Hodge, a psychologist in Ridgefield, CT. "And they say it's easier for children to get identified. I say that's not the truth and that I've been doing this for 30 years, and that even 10 years ago, I did not see the level of autism that I do see today."
Sure, we're better at detecting autism, she added, but the detection improvements have largely occurred at the low- to mid- level part of the spectrum. The higher rates of autism are occurring at the more severe end, in her experience.
A Polarizing Theory
Among the more controversial risk factors scientists are exploring is the role environmental toxins may play in the development of autism. Some scientists, doctors and mental health experts suspect that toxins like heavy metals, pesticides, chemicals, or pollution may interrupt the way genes are expressed or the way endocrine systems function, manifesting in symptoms of autism. But others firmly resist such claims, at least until more evidence comes forth. To date, studies have been mixed and many have been more associative than causative.
"Today, scientists are still trying to figure out whether there are other environmental changes that can explain this rise, but studies of this question didn't provide any conclusive answer," said Menashe, who also serves as the scientific director of the National Autism Research Center at BGU.
"It's not everything that makes Charlie. He's just like any other kid."
That inconclusiveness has not dissuaded some doctors from taking the perspective that toxins do play a role. "Autism rates are rising because there is a mismatch between our genes and our environment," said Julia Getzelman, a pediatrician in San Francisco. "The majority of our evolution didn't include the kinds of toxic hits we are experiencing. The planet has changed drastically in just the last 75 years –- it has become more and more polluted with tens of thousands of unregulated chemicals being used by industry that are having effects on our most vulnerable."
She cites BPA, an industrial chemical that has been used since the 1960s to make certain plastics and resins. A large body of research, she says, has shown its impact on human health and the endocrine system. BPA binds to our own hormone receptors, so it may negatively impact the thyroid and brain. A study in 2015 was the first to identify a link between BPA and some children with autism, but the relationship was associative, not causative. Meanwhile, the Food and Drug Administration maintains that BPA is safe at the current levels occurring in food, based on its ongoing review of the available scientific evidence.
Michael Mooney, President of St. Louis-based Delta Genesis, a non-profit organization that treats children struggling with neurodevelopmental delays like autism, suspects a strong role for epigenetics, which refers to changes in how genes are expressed as a result of environmental influences, lifestyle behaviors, age, or disease states.
He believes some children are genetically predisposed to the disorder, and some unknown influence or combination of influences pushes them over the edge, triggering epigenetic changes that result in symptoms of autism.
For Stefania Sterling, it doesn't really matter how or why she had an autistic child. That's only one part of Charlie.
"It's not everything that makes Charlie," she said. "He's just like any other kid. He comes with happy moments. He comes with sad moments. Just like my other three kids."
The Brave New World of Using DNA to Store Data
A panoramic view of DNA
Netscape co-founder-turned-venture capitalist billionaire investor Marc Andreessen once posited that software was eating the world. He was right, and the takeover of software resulted in many things. One of them is data. Lots and lots and lots of data. In the previous two years, humanity created more data than it did during its entire existence combined, and the amount will only increase. Think about it: The hundreds of 50KB emails you write a day, the dozens of 10MB photos, the minute-long, 350MB 4K video you shoot on your iPhone X add up to vast quantities of information. All that information needs to be stored. And that's becoming an issue as data volume outpaces storage space.
The race is on to find another medium capable of storing massive amounts of information in as small a space as possible.
"There won't be enough silicon to store all the data we need. It's unlikely that we can make flash memory smaller. We have reached the physical limits," Victor Zhirnov, chief scientist at the Semiconductor Research Corporation, says. "We are facing a crisis that's comparable to the oil crisis in the 1970s. By 2050, we're going to need to store 10 to the 30 bits, compared to 10 to the 23 bits in 2016." That amount of storage space is equivalent to each of the world's seven billion people owning almost six trillion -- that's 10 to the 12th power -- iPhone Xs with 256GB storage space.
The race is on to find another medium capable of storing massive amounts of information in as small a space as possible. Zhirnov and other scientists are looking at the human body, looking to DNA. "Nature has nailed it," Luis Ceze, a professor in the Department of Computer Science and Engineering at the University of Washington, says. "DNA is a molecular storage medium that is remarkable. It's incredibly dense, many, many thousands of times denser than the densest technology that we have today. And DNA is remarkably general. Any information you can map in bits you can store in DNA." It's so dense -- able to store a theoretical maximum of 215 petabytes (215 million gigabytes) in a single gram -- that all the data ever produced could be stored in the back of a tractor trailer truck.
Writing DNA can be an energy-efficient process, too. Consider how the human body is constantly writing and rewriting DNA, and does so on a couple thousand calories a day. And all it needs for storage is a cool, dark place, a significant energy savings when compared to server farms that require huge amounts of energy to run and even more energy to cool.
Picture it: tiny specks of inert DNA made from silicon or another material, stored in cool, dark, dry areas, preserved for all time.
Researchers first succeeded in encoding data onto DNA in 2012, when Harvard University geneticists George Church and Sri Kosuri wrote a 52,000-word book on A, C, G, and T base pairs. Their method only produced 1.28 petabytes per gram of DNA, however, a volume exceeded the next year when a group encoded all 154 Shakespeare sonnets and a 26-second clip of Martin Luther King's "I Have A Dream" speech. In 2017, Columbia University researchers Yaniv Erlich and Dina Zielinski made the process 60 percent more efficient.
The limiting factor today is cost. Erlich said the work his team did cost $7,000 to encode and decode two megabytes of data. To become useful in a widespread way, the price per megabyte needs to plummet. Even advocates concede this point. "Of course it is expensive," Zhirnov says. "But look how much magnetic storage cost in the 1980s. What you store today in your iPhone for virtually nothing would cost many millions of dollars in 1982." There's reason to think the price will continue to fall. Genome readers are improving, getting cheaper, faster, and smaller, and genome sequencing becomes cheaper every year, too. Picture it: tiny specks of inert DNA made from silicon or another material, stored in cool, dark, dry areas, preserved for all time.
"It just takes a few minutes to double a sample. A few more minutes, you double it again. Very quickly, you have thousands or millions of new copies."
Plus, DNA has another advantage over more traditional forms of storage: It's very easy to reproduce. "If you want a second copy of a hard disk drive, you need components for a disk drive, hook both drives up to a computer, and copy. That's a pain," Nick Goldman, a researcher at the European Bioinformatics Institute, says. "DNA, once you have that first sample, it's a process that is absolutely routine in thousands of laboratories around the world to multiply that using polymerase chain reaction [which uses temperature changes or other processes]. It just takes a few minutes to double a sample. A few more minutes, you double it again. Very quickly, you have thousands or millions of new copies."
This ability to duplicate quickly and easily is a positive trait. But, of course, there's also the potential for danger. Does encoding on DNA, the very basis for life, present ethical issues? Could it get out of control and fundamentally alter life as we know it?
The chance is there, but it's remote. The first reason is that storage could be done with only two base pairs, which would serve as replacements for the 0 and 1 digits that make up all digital data. While doing so would decrease the possible density of the storage, it would virtually eliminate the risk that the sequences would be compatible with life.
But even if scientists and researchers choose to use four base pairs, other safeguards are in place that will prevent trouble. According to Ceze, the computer science professor, the snippets of DNA that they write are very short, around 150 nucleotides. This includes the title, the information that's being encoded, and tags to help organize where the snippet should fall in the larger sequence. Furthermore, they generally avoid repeated letters, which dramatically reduces the chance that a protein could be synthesized from the snippet.
"In the future, we'll know enough about someone from a sample of their DNA that we could make a specific poison. That's the danger, not those of us who want to encode DNA for storage."
Inevitably, some DNA will get spilt. "But it's so unlikely that anything that gets created for storage would have a biological interpretation that could interfere with the mechanisms going on in a living organism that it doesn't worry me in the slightest," Goldman says. "We're not of concern for the people who are worried about the ethical issues of synthetic DNA. They are much more concerned about people deliberately engineering anthrax. In the future, we'll know enough about someone from a sample of their DNA that we could make a specific poison. That's the danger, not those of us who want to encode DNA for storage."
In the end, the reality of and risks surrounding encoding on DNA are the same as any scientific advancement: It's another system that is vulnerable to people with bad intentions but not one that is inherently unethical.
"Every human action has some ethical implications," Zhirnov says. "I can use a hammer to build a house or I can use it to harm another person. I don't see why DNA is in any way more or less ethical."
If that house can store all the knowledge in human history, it's worth learning how to build it.
Editor's Note: In response to readers' comments that silicon is one of the earth's most abundant materials, we reached back out to our source, Dr. Victor Zhirnov. He stands by his statement about a coming shortage of silicon, citing this research. The silicon oxide found in beach sand is unsuitable for semiconductors, he says, because the cost of purifying it would be prohibitive. For use in circuit-making, silicon must be refined to a purity of 99.9999999 percent. So the process begins by mining for pure quartz, which can only be found in relatively few places around the world.
Why Are Scientists and Patients Visiting This Island Paradise?
An inviting beach in Nassau, Bahamas.
Dr. Conville Brown, a cardiologist-researcher in The Bahamas, is at the helm of a fascinating worldwide project: He's leading a movement to help accelerate innovation by providing scientists and patients from around the globe with a legal, cost-effective, and ethically rigorous place to conduct medical research, as well as to offer commercial therapies that are already approved in some jurisdictions, but not others. He recently spoke with Editor-In-Chief Kira Peikoff about The Bahamas' emerging ascendance in the scientific world. This interview has been edited and condensed for brevity.
"You don't want to take shortcuts from the perspective of not giving proper due diligence to the process, but you also don't want it to be overwhelmed with red tape."
Tell me about the work you do in the Bahamas – what is the research focus?
We have a couple research opportunities here. Several years ago, we established the Partners Clinical Research Centre, the idea being that we can partner with different people in different territories in the world, including the United States, and be able to perform ethical research as would be defined and adjudicated by an institutional review board and a properly constituted ethics committee. We do all of this with FDA rigor, but in a non-FDA jurisdiction.
By doing this, we want to look for the science behind the research, and want to know that there is a sound clinical hypothesis that's going to be tested. We also want to know that the safety of the human subjects is assured as much as possible, and of course, assess the efficacy of that which you're testing. We want to do this in the same manner as the FDA, except in a more accelerated and probably less bureaucratic manner. You don't want to take shortcuts from the perspective of not giving proper due diligence to the process, but you also don't want it to be overwhelmed with red tape, so that what could be 3 months takes 3 years. A jet ski turns around a lot faster than the Queen Mary.
Why do you think the clinical research process in other countries like the U.S. has become burdened with red tape?
The litigious nature of society is a contributing factor. If people are negligent, they deserve to be sued. Unfortunately, all too often, some things get taken too far, and sometimes, the pendulum swings too far in the wrong direction and then it's counterproductive, so the whole process then becomes so very heavily regulated and financially burdensome. A lot of American companies have gone outside the country to get their clinical trials and/or device testing done because it's too phenomenally expensive and time-consuming. We seek to make sure the same degree of diligence is exercised but in a lesser time frame, and of course, at a much lower cost.
The other aspect, of course, is that there are certain opportunities where we have major jurisdictions, as in Europe, that have determined that a therapy or device is safe. Those services and devices we can utilize in the Bahamas--not as a clinical research tool, but as a therapy, which of course, the United States is not able to do without FDA approval. That could easily take another five years. So there is an opportunity for us in that window to make available such therapies and devices to the North American community. I like to call this "Advanced Medical Tourism" or "Advanced TransNational Medical Care." Instead of somebody flying nine hours to Europe, they can also now fly to the Bahamas, as little as half an hour away, and as long as we are satisfied that the science is sound and the approvals are in place from a senior jurisdiction, then we can legally serve any patient that is eligible for that particular therapy.
Dr. Conville Brown
(Courtesy)
Are you seeing an influx of patients for that kind of medical tourism?
The numbers are increasing. The stem cell legislation has now been in place for two to three years, so we have a number of entities including some large international companies coming to the shores of the Bahamas to provide some therapies here, and others for research. The vast majority of our clientele are from abroad, particularly the U.S. We fully plan to increase the traffic flow to the Bahamas for medical tourism, or preferably, TransNational Medical Care, Advanced and Conventional.
How do patients find out about available therapies and trials happening there?
Advertising in the international arena for something that is perfectly legal within the confines of Bahamas is par for the course. But the marketing efforts have not been that heavy while all the processes and procedures are being fine-tuned and the various entities are set up to handle more than 100 people at a time.
"We were able to accelerate those programs, and do it a lot less expensively than can be done in continental countries, but just as well."
What kind of research is being done by companies who have come to the Bahamas?
We've been involved in first-in-man procedures for neuromodulation of the cardiovascular system, where we inserted a device into the blood vessels and stimulated the autonomic nervous system with a view to controlling patients' blood pressure and heart rate in conditions such as congestive heart failure. We have also looked at injectable glucose sensors, to continually monitor the blood glucose, and via a chip, can send the blood glucose measurement back to the patient's cell phone. So the patient looks at his phone for his blood sugar. That was phenomenally exciting, the clinical trial was very positive, and the company is now developing a final prototype to commercialize the product. We were able to accelerate those programs, and do it a lot less expensively than can be done in continental countries, but just as well. The Bahamas has also crafted legislation specifically for regenerative medicine and stem cell research, so that becomes an additional major attraction.
Do you ever find that there is skepticism around going to the Caribbean to do science?
When it comes to clinical research and new medical devices, one might be skeptical about the level of medical/scientific expertise that is resident here. We're here to show that we do in fact have that expertise resident within The Partners Clinical Research Centre, within The Partners Stem Cell Centre, and we have formed our partnerships accordingly so that when prudent and necessary, we bring in additional expertise from the very territories that are seeking to accelerate.
Have you seen a trend toward increasing interest from researchers around the world?
Absolutely. One company, for example, is interested not only in the clinical side, but also the preclinical side--where you can have animal lab experiments done in the Bahamas, and being able to bridge that more readily with the clinical side. That presents a major opportunity for parties involved because again, the financial savings are exponential without compromising standards.
"A person who is 75 and frail, he doesn't want to wait to see if he will make it to 80 to benefit from the agent if it's approved in five years. Instead he can come to our center."
Where are some of these researchers from?
The United States, the Czech Republic, Russia, Canada, and South America. I expect significantly more interest once we promote the idea of European products having a welcome niche in the Bahamas, because we accept federal approvals from the U.S., Canada, and the European Union.
What do you think will be the first medical breakthrough to come out of research there?
One of the biggest killers in the world is heart disease, and we have the opportunity to implement a number of cardiac protocols utilizing stem cell therapy, particularly for those with no options. We just completed a state-of-the art medical center that we fashioned after the University of Miami that is getting ready for prime time. The sky will be the limit for the cardiac patient with respect to stem cell medicine.
Second, we are extremely pleased to be involved with a company called Longeveron, which is looking at how one might age better, and age more slowly, particularly with the administration of young blood and mesenchymal stem cells to frail, elderly candidates. Healthy young men have their mesenchymal stem cells harvested, expanded, and then administered to frail, elderly individuals with a view to improving their Frailty Index and functionality (feeling younger). There is a lot of interest in this arena, as one could imagine.
And herein lies the classical scenario for the Bahamas: Longeveron is now recruiting patients for its phase IIB double blind, placebo-controlled clinical trial at multiple sites across the U.S., which will add some two to three years to its data collection. Originally this work was done with NIH support at the University of Miami's Interdisciplinary Stem Cell Institute by Dr. Joshua Hare, and published in the Journal of Gerontology. So now, during the ongoing and expanded clinical trial, with those positive signals, we are able to have a commercially available clinical registry in the Bahamas. This has been approved by the ethics committee here, which is comprised of international luminaries in regenerative medicine. Longeveron will also be conducting an additional randomized clinical trial arm of same at our Centre in The Bahamas, The Partners Stem Cell Centre.
Can you clarify what you mean by "registry"?
In other words, you still have to fit the eligibility criteria to receive the active agent, but the difference is that in a placebo-controlled double-blind clinical trial, the physician/researcher and the patient don't know if they are getting the active agent or placebo. In the registry, there is no placebo, and you know you're getting the active agent, what we call "open label." You're participating because of the previous information on efficacy and safety.
A person who is 75 and frail, he doesn't want to wait to see if he will make it to 80 to benefit from the agent if it's approved in five years. Instead he can come to our center, one of the designated centers, and as long as he meets the inclusion criteria, may participate in said registry. The additional data from our patients can bolster the numbers in the clinical trial, which can contribute to the FDA approval process. One can see how this could accelerate the process of discovery and acceptance, as well as prove if the agent was not as good as it was made out to be. It goes both ways.
"We would love to be known as a place that facilitates the acceleration of ethical science and ethical therapies, and therefore brings global relief to those in need."
Do you think one day the Bahamas will be more well-known for its science than its beaches?
I doubt that. What I would like to say is that the Bahamas would love to always be known for its beautiful beaches, but we would also like to be known for diversity and innovation. Apart from all that beauty, we can still play a welcoming role to the rest of the scientific world. We would love to be known as a place that facilitates the acceleration of ethical science and ethical therapies, and therefore brings global relief to those in need.
Kira Peikoff was the editor-in-chief of Leaps.org from 2017 to 2021. As a journalist, her work has appeared in The New York Times, Newsweek, Nautilus, Popular Mechanics, The New York Academy of Sciences, and other outlets. She is also the author of four suspense novels that explore controversial issues arising from scientific innovation: Living Proof, No Time to Die, Die Again Tomorrow, and Mother Knows Best. Peikoff holds a B.A. in Journalism from New York University and an M.S. in Bioethics from Columbia University. She lives in New Jersey with her husband and two young sons. Follow her on Twitter @KiraPeikoff.