Autism Spectrum Disorder (ASD) is a lifelong neurodevelopmental condition characterized by differences in social communication, along with restricted or repetitive patterns of behavior, interests, or activities. While once considered a condition primarily affecting children, research now focuses on the experiences and outcomes of adults on the spectrum. Understanding the trajectory of health and longevity in this population is important. Recent large-scale investigations into lifespan have provided clearer, though often concerning, data regarding the health disparities that affect autistic adults, highlighting the need to address systemic issues impacting life expectancy.
Current Life Expectancy Statistics
Research suggests a notable difference in average lifespan for autistic adults compared to the general population, though specific figures vary based on co-occurring conditions. A comprehensive study using United Kingdom health data found that the average estimated life expectancy for autistic men without an intellectual disability was approximately 74.6 years, and for autistic women without intellectual disability, it was around 76.8 years. These figures are several years lower than the general population’s average of about 80 years for men and 83 years for women. These findings consistently demonstrate a significant health inequality.
The presence of a co-occurring intellectual disability (ID) is strongly associated with a further reduction in estimated lifespan. Autistic men with ID had an average estimated life expectancy of 71.7 years, while autistic women with ID had the lowest estimate at 69.6 years. This disparity underscores the impact of complex support needs and multiple health conditions on longevity. Gathering precise statistics is challenging because many autistic adults remain undiagnosed, meaning current data is based primarily on individuals who have received a formal diagnosis.
Elevated Risks from Physical Health Comorbidities
A significant factor contributing to a reduced lifespan is the high prevalence of co-occurring physical health conditions, or comorbidities. Neurological conditions like epilepsy and seizure disorders are common and represent a leading cause of premature death, particularly for autistic individuals who also have an intellectual disability. The mortality risk from neurological causes is estimated to be several times higher in the autistic population compared to the general population.
Beyond neurological issues, autistic adults face increased risks for other systemic health problems. Gastrointestinal (GI) disorders, such as chronic constipation and irritable bowel syndrome, are frequently reported and significantly impact overall health. Cardiovascular risk factors are also elevated, sometimes compounded by sedentary lifestyles or the side effects of psychotropic medications used to manage co-occurring mental health conditions.
These physical health issues often go undiagnosed or are inadequately managed, a phenomenon sometimes termed diagnostic overshadowing. Communication difficulties or challenges in recognizing and reporting internal states, such as pain, can lead to delayed or missed diagnoses. Sensory sensitivities or anxiety related to clinical environments also act as powerful barriers, preventing routine check-ups and preventative care. This lack of appropriate and accessible healthcare for chronic conditions directly contributes to premature mortality.
Mortality Linked to Intellectual Disability and Mental Health
The causes of premature mortality differ significantly depending on whether an autistic individual has a co-occurring intellectual disability (ID). For those with ID, physical complications are often the primary driver of reduced lifespan. Seizures and other neurological issues are more common in this subgroup and pose a substantial mortality risk.
In contrast, for autistic adults without an intellectual disability, the leading cause of early death is suicide. Autistic adults are estimated to be at a substantially higher risk of death by suicide than the general population, with some studies suggesting a risk up to seven times greater. The risk of suicidal ideation and attempts is particularly pronounced, with rates of ideation reported to be up to 25 times higher than in non-autistic adults.
This mental health crisis is often linked to chronic factors like social isolation, unemployment, and the psychological burden of masking autistic traits to fit into a neurotypical world. Autistic women, in particular, appear to face a disproportionately high risk of suicide. External causes beyond suicide, such as accidents and violence, also contribute to elevated mortality rates across the spectrum. Accidents like drowning, suffocation, and accidental poisoning have been reported as significant causes of death.
Improving Health Outcomes Through Accessible Care
Addressing the reduced life expectancy requires systemic changes focused on improving the accessibility and quality of healthcare. A fundamental step is fostering autism competence among medical professionals through specialized training. Clinicians need a better understanding of how autism presents across the lifespan and how to navigate communication differences and sensory sensitivities during appointments.
Healthcare settings must be adapted to be more neuroinclusive. This can involve concrete changes such as offering longer appointment times to allow for processing and communication, or providing sensory-friendly waiting areas with reduced light and noise. These adjustments help reduce the anxiety that acts as a major barrier to seeking care, facilitating earlier diagnosis and management of physical and mental health issues.
Systemic solutions should focus on better screening for co-occurring conditions, particularly mental health issues and common physical comorbidities like GI disorders and epilepsy. By recognizing the interconnectedness of physical and mental health challenges in autistic adults, healthcare systems can move toward a holistic approach that proactively addresses chronic illnesses and the mental health crisis. Ultimately, reducing the premature mortality gap depends on eliminating the pervasive health inequalities that affect the autistic community.