The question of whether people with Autism Spectrum Disorder (ASD) have a reduced lifespan is a serious topic addressed by current research. ASD is a neurodevelopmental difference affecting how individuals communicate, interact, and experience the world. While autism itself does not cause premature death, it is strongly associated with co-occurring medical and mental health conditions that significantly impact longevity. Examining data on life expectancy, physical illnesses, and mental health risks provides a clearer understanding of this health disparity.
Understanding the Data on Life Expectancy
Epidemiological studies consistently show a reduced life expectancy for the autistic population, often called the “mortality gap.” Recent analyses suggest that autistic individuals without a co-occurring intellectual disability (ID) have a life expectancy approximately six years shorter than the general population. This places their estimated lifespan in the mid-70s, compared to the early 80s for neurotypical peers.
The life expectancy gap widens considerably for individuals who have both ASD and an intellectual disability. For this group, the reduction in lifespan can be over a decade, with some studies showing an average life expectancy in the late 60s or lower. Older research suggested a reduction of 16 to 18 years overall, but more recent population-wide studies indicate this figure is likely an overestimation reflecting cohorts with the highest support needs.
Impact of Co-occurring Physical Health Conditions
The primary drivers of premature mortality are chronic physical health conditions that occur at disproportionately high rates, not the core features of autism. Epilepsy is a significant neurological comorbidity, affecting an estimated 12% of the autistic population, far exceeding the general rate. For individuals with co-occurring intellectual disability, epilepsy prevalence can be as high as 30 to 46%.
The increased risk of death from epilepsy is often due to Sudden Unexpected Death in Epilepsy (SUDEP), which accounts for nearly one-fifth of all deaths in people with epilepsy. Risk factors for SUDEP include difficult-to-control seizures and intellectual disability. Since seizures often begin in infancy or adolescence, their presence significantly increases overall mortality risk.
Cardiovascular and metabolic conditions also contribute substantially to the mortality gap. Autistic adults show a higher prevalence of cardiovascular disease risk factors, including obesity (over 70%), high cholesterol, and high blood pressure. Antipsychotic medications, often prescribed for challenging behaviors, are strongly linked to developing diabetes and other metabolic issues. This is compounded by chronic stress, poor sleep quality, and lifestyle factors related to sensory or executive function differences.
Chronic gastrointestinal (GI) issues, such as inflammatory bowel disease (IBD), constipation, and chronic diarrhea, are approximately four times more common in the autistic population. These conditions are linked to chronic inflammation and gut-brain axis dysregulation. The challenge of communicating internal physical pain, particularly for non-speaking individuals, can lead to delayed diagnosis and inadequate treatment of serious conditions like IBD.
Addressing Mental Health and Vulnerability Risks
Non-medical factors related to mental health and external vulnerability contribute significantly to premature death. Suicide risk is drastically elevated, particularly among autistic adults without an intellectual disability, who face a risk up to nine times higher than the general population. This heightened risk is closely tied to the psychological burden of “masking” or “camouflaging,” which involves suppressing autistic traits to fit into neurotypical social settings.
This constant effort leads to severe mental exhaustion known as autistic burnout, which fuels anxiety, depression, and suicidal ideation. The persistent feeling of social isolation and the strain of maintaining a false presentation compromise mental well-being. Suicide is a leading cause of death in this community segment, highlighting the impact of systemic social pressure and lack of acceptance.
Accidental death is also a major concern, especially for children and those with higher support needs. Individuals with autism are nearly three times more likely to die from unintentional injuries than the general population. Drowning, suffocation, and asphyxiation account for the majority of these deaths. Children with autism are 160 times more likely to die from drowning than other children, often due to elopement or “wandering” combined with an attraction to water.
Systemic failures in healthcare, known as diagnostic overshadowing, further amplify these risks. This occurs when a clinician mistakenly attributes a new physical or mental health symptom to the existing autism diagnosis, leading to delayed or missed treatment. For example, a behavioral change signaling severe abdominal pain may be dismissed as “just part of the autism,” preventing investigation into a treatable underlying cause.
Improving Health Outcomes and Lifespan
Addressing the mortality gap requires systemic changes focused on proactive and individualized healthcare. A primary strategy is mitigating the risk of accidental death through targeted safety interventions. Adaptive swimming lessons, focusing on water safety skills, are recommended immediately upon diagnosis due to the high risk of drowning associated with elopement behavior.
Healthcare provider education is paramount to combat diagnostic overshadowing. Training medical professionals to recognize that behavioral changes can be the sole manifestation of physical illness, such as GI pain, is necessary for timely intervention. Providers must also make environmental accommodations, such as dimming lights or reducing noise in waiting rooms, to create accessible healthcare settings that minimize sensory distress.
Mental health interventions must be tailored to address unique stressors like masking and burnout. This includes promoting community acceptance and providing neurodiversity-affirming mental health support, such as adapted cognitive behavioral therapy. Focusing on integrated care that respects the unique needs of autistic individuals and proactively addresses co-occurring conditions can significantly improve health outcomes and close the life expectancy gap.