All-cause and cause-specific mortality in people with autism spectrum disorder: A systematic review

Background: The aim of this systematic review was to synthesise the current literature on all-cause and cause-specific mortality in individuals with autism spectrum disorders (ASD) to identify whether they experience an increased risk of mortality compared to the general population and to establish which specific causes of death are most prevalent in ASD individuals.
Method: Medline, Embase, CINAHL and PsycINFO databases were searched. The review was registered with PROSPERO (CRD42021219582).
Results: 26 of the 8,505 retrieved papers were included. All 26 studies reported an increased risk of mortality for individuals with ASD. The highest standardised mortality ratio for people with ASD was 5.6 (95% CI= 2.5-10.5). Five studies suggested that females with ASD were at an even greater risk of death when compared to their male counterparts. The most common causes of deaths were from external causes (particularly suicide) and neurological diseases.
Conclusions: Recognising the increased mortality experienced by individuals with ASD is an important factor in how clinicians, support workers and healthcare systems in general should plan and approach care for this population. Although a significant portion of deaths in this group occur due to intentional or unintentional external causes, the reviewed literature also indicates that many people with ASD die from underlying health conditions. As the increased mortality risk seems to be partially mediated by the co-occurrence of other conditions, it is of great importance to provide an increased level of support and care for this population.