Discovering risk factors
Scientists use epidemiological studies to better understand the impact of environmental risk factors and their interaction with genetic predisposition to autism spectrum disorder (ASD). Epidemiological studies come in many types of designs. They can compare “cases” (those with ASD) to “controls” (those without ASD). They can compare cohorts, or groups of people who have been exposed to particular environmental factors. They can look at rates of autism and exposures in whole populations. Epidemiological studies may include information from medical records, direct observations, self-reports, occupational histories and biological samples (blood and genetic material, for example). Each approach has its own strengths and opportunities for identifying potential risk factors.
Given the diverse nature of the way data is collected, as well as how diverse individuals with ASD are, future studies will depend on multi-site and multi-disciplinary collaborations. These collaborations need to address issues around different subgroups of ASD. They need to look at gender differences, rare exposures, potentially modifiable exposures and gene/environment interactions.
To help reach these goals, Autism Speaks and the National Institute of Environmental Health Sciences (NIEHS) formed the Environmental Epidemiology of Autism Research Network (EEARN). The goals of the network are to:
1) Support and encourage collaborations across research sites, especially research projects that involve rare subgroups or exposures.
2) Provide a framework to share information and research protocols, including a website.
3) Create opportunities for new researchers, specifically in probing existing data for still undiscovered findings.
In 2011, Autism Speaks supported two multisite projects. The first will utilize the AGRE database together with the hazardous air pollution database to examine the relationship between air particulate matter and autism risk. The second will develop and validate a standardized exposure questionnaire that can be used in a number of research studies, especially those primarily focused on genetic or clinical outcomes, to better study gene/environment interactions.
In 2012, leading epidemiologists from around the world met at the International Society for Environmental Epidemiology, in Columbia, S.C. They presented a symposium titled Challenges and Pitfalls of Multi-Site Collaboration in International Autism Environmental Epidemiology Studies. The goals of the symposium were to share study approaches, new technology and findings with autism researchers as well as with epidemiologists outside of the field of autism. The presenters also discussed solutions to address challenges of studying environmental epidemiology of ASD internationally. To read more about the presentations, click here.
For more information about the network, please email firstname.lastname@example.org .