Editor's note: Francesca Happé is president of the International Society for Autism Research, a professor of cognitive neuroscience, and director of the MRC Social, Genetic and Developmental Psychiatry Centre at the Institute of Psychiatry at King's College London. Opinions expressed in this article are solely those of the author.
(CNN) -- As the world's leading autism researchers and advocates gathered at the International Meeting for Autism Research last weekend to share the latest discoveries about autism spectrum disorder, a strong theme emerged: Autism is growing up.
When you think of autism, you probably think of young children. But children with autism grow up to be adults with autism, and eventually (God willing) elderly people with autism.
In fact, most people with autism are adults, and most adults with autism lack services -- or even a diagnosis.
In her conference keynote address, Marsha Mailick, director of the Waisman Center at the University of Wisconsin-Madison, shared data gleaned from 10 years of following the lives of more than 400 people with autism, starting in 1998. This study was prescient; adults are vastly underrepresented in autism research, and longitudinal studies into old age are badly needed.
Some good news emerged from Mailick's study: Autistic symptoms, such as impaired verbal and nonverbal communication and social interaction, and rigid/repetitive behaviors, decreased over time among one-third to half of the study participants, and stayed stable in many others. Independent living skills remained stable in this group, as well.
However, leaving high school was a time of vulnerability for participants when, especially in low-income families, previous gains in skills and behavior slowed or plateaued. Work or study was minimal for a quarter of the individuals with autism, and over time women with autism in particular showed a decline in vocationally occupied hours.
The impact on self-esteem and mental health can only be imagined; people with autism are very prone to anxiety and depression.
The impact of autism on physical health was also highlighted at the conference by new data from Dr. Lisa Croen of Kaiser Permanente, who reported highly elevated rates of hypertension, diabetes and obesity from the medical records of more than 2,000 adults with autism (compared with 20,000 comparison adults without autism).
What can we take away from this? Physicians need to be aware that patients with autism may have communication difficulties that limit their reports of early health problems, and sensory sensitivities that may reduce their tolerance for investigations and treatment.
The children first described as "autistic" by Leo Kanner in 1943 are now in their seventies, yet there are no more than a handful of research papers on the elderly with ASD.
Dr. Joe Piven of the University of North Carolina spent three years trying to trace elderly people with autism, and reported at this meeting on just 20 individuals he and his colleagues had found, all with intellectual disabilities.
Intriguingly, this group of severely affected older adults with autism showed high rates of Parkinson-like movement problems. Do these reflect a history of medication or premature aging, or are they a clue to a previously unknown neuropathology associated with "grownup" autism?
More clues will come from work being carried out in the Netherlands by Hilde Geurts and her colleagues, who presented at the conference this year.
Their preliminary findings from approximately 200 older adults with autism and comparison adults without the disorder show quality of life is lower in adults with autism, and cognitive problems were higher, but in their group of 19- to 78-year-olds, age did not predict these difficulties.
An enormous amount of exciting research emerged from the conference, much of it focused on improving detection and diagnosis, expanding treatment options, and, in certain instances, even reversing core symptoms for some young children with ASD.
But as we expand our research, we must also devote more resources to improving adult services and better addressing lifespan issues of those living with ASD today.
It's not just about the kids anymore.