A meta-analysis on the impact of psychiatric disorders and maltreatment on cognition

Few studies have attempted to describe the range of cognitive impairments in individuals with psychiatric disorders who experienced maltreatment as children. The aims of this meta-analysis were to establish the impact of maltreatment and psychiatric disorders on cognition, and to examine the change in impact from childhood to adulthood.

Twelve publications from 1970 to 2013 were included, with the following inclusion criteria: (a) individuals with a psychiatric disorder who experienced maltreatment, (b) use of at least 1 standardized neuropsychological measure, and (c) use of a control group without any psychiatric disorder or mistreatment. The majority of studies (10/12) were about posttraumatic stress disorder. Several effect sizes were calculated (Hedge's g) according to the cognitive domains.

The results of the meta-analysis demonstrate that the combination of psychiatric disorders and childhood maltreatment has a negative impact on global cognitive performance, with a moderate effect size (g = -0.59). The most affected cognitive domains for individuals aged 7- to 18-years-old were visual episodic memory (g = -0.97), executive functioning (g = -0.90), and intelligence (g = -0.68). For individuals over the age of 18-years-old, the most affected cognitive domains were verbal episodic memory (g = -0.77), visuospatial/problem solving (g = -0.73), and attention (g = -0.72). The impact of maltreatment and psychiatric disorders was greater in children than in adults (slope = 0.008, p < .002).

The results suggest that exposure to maltreatment and the presence of psychiatric disorders have a broad impact on cognition, with specific neuropsychological profile.