Psychiatric diagnoses occur more frequently in people with autism compared with the general population across the lifespan, according to research published in The Lancet Psychiatry. These co-occurring mental health or psychiatric conditions span a wide range of disorders and impair quality of life. Researchers therefore sought to improve prevalence estimates and identify study moderators to enhance recognition and care, as well as to guide future research.
The systematic review and meta-analysis included data from MEDLINE, Embase, PsychINFO, Scopus, Web of Science, and grey literature that reported original research on co-occurring mental health conditions in autism populations using an observational design. Data from 96 studies included confirmed clinical diagnoses of co-occurring conditions and autism using Diagnostic and Statistical Manual of Mental Disorders or International Statistical Classification of Diseases and Related Health Problems criteria. The researchers investigated trauma and stressor-related disorders, substance-related and addictive disorders, and gender dysphoria using random-effects models.
The researchers found a prevalence of 28% for attention-deficit/hyperactivity disorder; 20% for anxiety disorders; 13% for sleep-wake disorders; 12% for disruptive, impulse-control, and conduct disorders; 11% for depressive disorders; 9% for obsessive-compulsive disorder; 5% for bipolar disorders; and 4% for schizophrenia spectrum disorders.
The prevalence estimates in the clinical sample-based studies were higher than in population- and registry-based studies. Age, gender, intellectual functioning, country of study, and publication year were all associated with heterogeneous prevalence estimates.
The study was limited by its strict eligibility criteria that excluded potentially useful information. Additionally, the meta-regression analyses may be underpowered.
The researchers state that these findings warrant further research “to uncover shared underpinnings and sources of vulnerability associated with autism. Mental health promotion should be an essential component of care for all individuals on the autism spectrum.” They also advise that “[v]alid and standardized measures of mental health challenges in people with autism or other neurodevelopmental disabilities are necessary to facilitate accurate diagnosis” and to promote effective care.
Lai M-C, Kassee C, Besney R, et al. Prevalence of co-occurring mental health diagnoses in the autism population: a systematic review and meta-analysis. Lancet Psychiatry. 2019;6(10):819-829.