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."
Men and Women Experience Pain Differently. Learning Why Could Lead to Better Drugs.
According to the CDC, one fifth of American adults live with chronic pain, and women are affected more than men.
It's been more than a decade since Jeannette Rotondi has been pain-free. A licensed social worker, she lives with five chronic pain diagnoses, including migraines. After years of exploring treatment options, doctors found one that lessened the pain enough to allow her to "at least get up."
"With all that we know now about genetics and the immune system, I think the future of pain medicine is more precision-based."
Before she says, "It was completely debilitating. I was spending time in dark rooms. I got laid off from my job." Doctors advised against pregnancy; she and her husband put off starting a family for almost a decade.
"Chronic pain is very unpredictable," she says. "You cannot schedule when you'll be in debilitative pain or cannot function. You don't know when you'll be hit with a flare. It's constantly in your mind. You have to plan for every possibly scenario. You need to carry water, medications. But you can't plan for everything." Even odors can serve as a trigger.
According to the CDC, one fifth of American adults live with chronic pain, and women are affected more than men. Do men and women simply vary in how much pain they can handle? Or is there some deeper biological explanation? The short answer is it's a little of both. But understanding the biological differences can enable researchers to develop more effective treatments.
While studies in animals are straightforward (they either respond to pain or they don't), humans are more complex. Social and psychological factors can affect the outcome. For example, one Florida study found that gender role expectations influenced pain sensitivity.
"If you are a young male and you believe very strongly that men are tougher than women, you will have a much higher threshold and will be less sensitive to pain," says Robert Sorge, an associate professor at the University of Alabama at Birmingham whose lab researches the immune system's involvement in pain and addiction.
He also notes, "We looked at transgender women and their pain sensitivity in comparison to cis men and women. They show very similar pain sensitivity to cis women, so that may reduce the impact of genetic sex in terms of what underlies that sensitivity."
But the difference goes deeper than gender expectations. There are biological differences as well. In 2015, Sorge and his team discovered that pain stimuli activated different immune cells in male and female rodents and that the presence of testosterone seemed to be a factor in the response.
More recently, Ted Price, professor of neuroscience at University of Texas, Dallas, examined pain at a genetic level, specifically looking at the patterns of RNA, which are single-stranded molecules that act as a messenger for DNA. Price noted that there were differences in these patterns that coincided with whether an individual experienced pain.
Price explains, "Every cell in your body has DNA, but the RNA that is in the cells is different for every cell type. The RNA in any particular cell type, like a neuron, can change as a result of some environmental influence like an injury. We found a number of genes that are potentially causative factors for neuropathic pain. Those, interestingly, seemed to be different between men and women."
Differences in treatment also affect pain response. Sorge says, "Women are experiencing more pain dismissal and more hostility when they report chronic pain. Women are more likely to have their pain associated with psychological issues." He adds that this dismissal may require women to exaggerate symptoms in order to be believed.
This can impact pain management. "Women are more likely to be prescribed and to use opioids," says Dr. Roger B. Fillingim, Director of Pain Research and Intervention Center of Excellence at the University of Florida. Yet, when self-administering pain meds, "women used significantly less opioids after surgery than did men." He also points out that "men are at greater risk for dose escalation and for opioid-related death than are women. So even though more women are using opioids, men are more likely to die from opioid-related causes."
Price acknowledges that other drugs treat pain, but "unfortunately, for chronic pain, none of these drugs work very well. We haven't yet made classes of drugs that really target the underlying mechanism that causes people to have chronic pain."
New drugs are now being developed that "might be particularly efficacious in women's chronic pain."
Sorge points out that there are many variables in pain conditions, so drugs that work for one may be ineffective for another. "With all that we know now about genetics and the immune system, I think the future of pain medicine is more precision-based, where based on your genetics, your immune status, your history, we may eventually get to the point where we can say [certain] drugs have a much bigger chance of working for you."
It will take some time for these new discoveries to translate into effective treatments, but Price says, "I'm excited about the opportunities. DNA and RNA sequencing totally changes our ability to make these therapeutics. I'm very hopeful." New drugs are now being developed that "might be particularly efficacious in women's chronic pain," he says, because they target specific receptors that seem to be involved when only women experience pain.
Earlier this year, three such drugs were approved to treat migraines; Rotondi recently began taking one. For Rotondi, improved treatments would allow her to "show up for life. For me," she says, "it would mean freedom."
Deaf Scientists Just Created Over 1000 New Signs to Dramatically Improve Ability to Communicate
Sarah Latchney, the first deaf PhD student at the University of Rochester School of Medicine & Dentistry, pictured here at work at a lab in the department of environmental sciences.
For the deaf, talent and hard work may not be enough to succeed in the sciences. According to the National Science Foundation, deaf Americans are vastly underrepresented in the STEM fields, a discrepancy that has profound economic implications.
The problem with STEM careers for the deaf and hard-of-hearing is that there are not enough ASL signs available.
Deaf and hard-of-hearing professionals in the sciences earn 31 percent more than those employed in other careers, according to a 2010 study by the National Technical Institute for the Deaf (NTID) in Rochester, N.Y., the largest technical college for deaf and hard-of-hearing students. But at the same time, in 2017, U.S. students with hearing disabilities earned only 1.1 percent of the 39,435 doctoral degrees awarded in science and engineering.
One reason so few deaf students gravitate to science careers and may struggle to complete doctoral programs is the communication chasm between deaf and hard-of-hearing scientists and their hearing colleagues.
Lorne Farovitch is a doctoral candidate in biomedical science at the University of Rochester of New York. Born deaf and raised by two deaf parents, he communicated solely in American Sign Language (ASL) until reaching graduate school. There, he became frustrated at the large chunk of his workdays spent communicating with hearing lab mates and professors, time he would have preferred spending on his scientific work.
The problem with STEM careers for the deaf and hard-of-hearing is that there are not enough ASL signs available, says Farovitch. Names, words, or phrases that don't exist in ASL must be finger spelled — the signer must form a distinct hand shape to correspond with each letter of the English alphabet, a tedious and time-consuming process. For instance, it requires 12 hand motions to spell out the word M-I-T-O-C-H-O-N-D-R-I-A. Imagine repeating those motions countless times a day.
To bust through this linguistic quagmire, Farovitch, along with a team of deaf STEM professionals, linguists, and interpreters, have been cooking up signs for terms like Anaplasma phagocytophilum, the tick-borne bacterium Farovitch studies. The sign creators are then videotaped performing the new signs. Those videos are posted on two crowd-sourcing sites, ASLcore.org and ASL Clear.
The beauty of ASL is you can express an entire concept in a single sign, rather than by the name of a word.
"If others don't pick it up and use it, a sign goes extinct," says Farovitch. Thus far, more than 1,000 STEM terms have been developed on ASL Clear and 500 vetted and approved by the deaf STEM community, according to Jeanne Reis, project director of the ASL Clear Project, based at The Learning Center for the Deaf in Framingham, Mass.
The beauty of ASL is you can express an entire concept in a single sign, rather than by the name of a word. The signs are generally intuitive and wonderfully creative. To express "DNA" Farovitch uses two fingers of each hand touching the tips of the opposite hand; then he draws both the hands away to suggest the double helix form of the hereditary material present in most organisms.
"If you can show it, you can understand the concept better,'' says the Canadian-born scientist. "I feel I can explain science better now."
The hope is that as ASL science vocabulary expands more, deaf and hard-of-hearing students will be encouraged to pursue the STEM fields. "ASL is not just a tool; it's a language. It's a vital part of our lives," Farovitch explains through his interpreter.
The deaf community is diverse—within and beyond the sciences. Sarah Latchney, PhD, an environmental toxicologist, is among the approximately 90 percent of deaf people born to hearing parents. Hers made sure she learned ASL at an early age but they also sent Latchney to a speech therapist to learn to speak and read lips. Latchney is so adept at both that she can communicate one-on-one with a hearing person without an interpreter.
Like Favoritch, Latchney has developed "conceptually accurate" ASL signs but she has no plans to post them on the crowd-sourcing sites. "I don't want to fix [my signs]; it works for me," she explains.
Young scientists like Farovitch and Latchney stress the need for interpreters who are knowledgeable about science. "When I give a presentation I'm a nervous wreck that I'll have an interpreter who may not have a science background," Latchney explains. "Many times what I've [signed] has been misinterpreted; either my interpreter didn't understand the question or didn't frame it correctly."
To enlarge the pool of science-savvy interpreters, the University of Rochester will offer a new masters degree program: ASL Interpreting in Medicine and Science (AIMS), which will train interpreters who have a strong background in the biological sciences.
Since the Americans with Disabilities Act was enacted in 1990, opportunities in higher education for deaf and hard-of-hearing students have opened up in the form of federally funded financial aid and the creation of student disability services on many college campuses. Still, only 18 percent of deaf adults have graduated from college, compared to 33 percent of the general population, according to a survey by the U.S. Census Bureau in 2015.
The University of Rochester and the Rochester Institute of Technology, home to NTID, have jointly created two programs to increase the representation of deaf and hard-of-hearing professionals in the sciences. The Rochester Bridges to the Doctorate Program, which Farovitch is enrolled in, prepares deaf scholars for biomedical PhD programs. The Rochester Postdoctoral Partnership readies deaf postdoctoral scientists to successfully attain academic research and teaching careers. Both programs are funded by the National Institutes of Science. In the last five years, the University of Rochester has gone from zero deaf postdoctoral and graduate students to nine.
"Deafness is not a problem, it's just a difference."
It makes sense for these two private universities to support strong programs for the deaf: Rochester has the highest per capita population of deaf or hard-of-hearing adults younger than 65 in the nation, according to the U.S. Census. According to the U.S. Department of Education, there are about 136,000 post-secondary level students who are deaf or hard of hearing.
"Deafness is not a problem, it's just a difference," says Farovitch. "We just need a different way to communicate. It doesn't mean we require more work."