Transdiagnostic Neurocognitive Deficits in Psychiatry: A Review of Meta-Analyses

Several meta-analyses have been published that evaluate the impact of psychiatric disorders on neuropsychological functioning. The first objective was to investigate transdiagnostic neurocognitive impairments across several psychiatric disorders. The second objective was to document transdiagnostic neurocognitive impairments across the life span. A literature search was conducted to identify all meta-analyses of neurocognitive deficits in psychiatry published prior to August, 2017. The following psychiatric disorders were considered: mood disorders, psychotic disorders, autism spectrum disorders, attention-deficit/hyperactivity disorder (ADHD), and anxiety disorders. The R-AMSTAR (Revised Assessment of Multiple Systematic Reviews) was used to assess methodological quality. The final selection included only the most rigorous meta-analyses. A total of 36 meta-analyses were included. They documented neurocognitive impairments in schizophrenia, autism spectrum disorder, ADHD, bipolar disorder, depression, obsessive-compulsive disorder, and posttraumatic stress disorder. Across all disorders, deficits in executive functions and in episodic memory were the most severe and the most frequently reported. Severe deficits in executive functions were frequently reported across age groups. Neurocognitive impairments are observed in almost all disorders, in all age groups. Some neurocognitive impairments are more frequently reported across all disorders. Deficits in executive functions and episodic memory appear to be transdiagnostic and to remain relatively stable across the life span. Transdiagnostic factors could be key targets for transdiagnostic cognitive interventions in psychiatric populations. Neurobiological, neuropsychological, and genetic hypotheses of transdiagnostic neurocognitive impairments are discussed.