Occurrence of psychosis and bipolar disorder in adults with autism: A systematic review and meta-analysis

Objective: Evidence suggests that individuals with autism spectrum disorder have increased rates of co-occurring psychosis and/or bipolar disorder. Considering the peak age of onset for psychosis and bipolar disorder occurs in adulthood, we investigated the co-occurrence of these disorders in adults with autism. Methods: We conducted a systematic review and meta-analysis (PROSPERO Registration Number: CRD42018104600) to (1) examine the prevalence of psychosis and bipolar disorder in adults with autism, and (2) review potential risk factors associated with their co-occurrence. Results: Fifty-three studies were included. The pooled prevalence for the co-occurrence of psychosis in adults with autism was 9.4 % (N = 63,657, 95 %CI = 7.52, 11.72). The pooled prevalence for the co-occurrence of bipolar disorders in adults with autism was 7.5 % (N = 31,739, 95 %CI = 5.79, 9.53). Conclusions: Psychosis and bipolar disorder occur at a substantially higher prevalence in adults with autism compared to general population estimates. While there is an overall dearth of research examining risk factors for these disorders in autism, males had increased likelihood of co-occurring psychosis, and females of co-occurring bipolar disorder. These results highlight the need for ongoing assessment and monitoring of these disorders in adults with autism.