Project Among African-Americans to Explore Risks for Schizophrenia (PAARTNERS): Evidence for Impairment and Heritability of Neurocognitive Functioning in Families of Schizophrenia Patients

Abstract

Objective Neurocognitive impairments in schizophrenia are well replicated and widely regarded as candidate endophenotypes that may facilitate understanding of schizophrenia genetics and pathophysiology. The Project Among African-Americans to Explore Risks for Schizophrenia (PAARTNERS) aims to identify genes underlying liability to schizophrenia. The unprecedented size of its study group (N=1,872), made possible through use of a computerized neurocognitive battery, can help further investigation of the genetics of neurocognition. The current analysis evaluated two characteristics not fully addressed in prior research: 1) heritability of neurocognition in African American families and 2) relationship between neurocognition and psychopathology in families of African American probands with schizophrenia or schizoaffective disorder. Method Across eight data collection sites, patients with schizophrenia or schizoaffective disorder (N=610), their biological relatives (N=928), and community comparison subjects (N=334) completed a standardized diagnostic evaluation and the computerized neurocognitive battery. Performance accuracy and response time (speed) were measured separately for 10 neurocognitive domains. Results The patients with schizophrenia or schizoaffective disorder exhibited less accuracy and speed in most neurocognitive domains than their relatives both with and without other psychiatric disorders, who in turn were more impaired than comparison subjects in most domains. Estimated trait heritability after inclusion of the mean effect of diagnostic status, age, and sex revealed significant heritabilities for most neurocognitive domains, with the highest for accuracy of abstraction/ flexibility, verbal memory, face memory, spatial processing, and emotion processing and for speed of attention. Conclusions Neurocognitive functions in African American families are heritable and associated with schizophrenia. They show potential for gene-mapping studies.

Evaluation of HLA Polymorphisms in Relation to Schizophrenia Risk and Infectious Exposure

“…17,18 Briefly, all participants were interviewed using the Diagnostic Interview for Genetic Studies. Additional clinical information was obtained from medical records and consenting relatives.…”

Persistent infection with neurotropic herpes viruses and cognitive impairment

“…Parficipants in this study were African-Americans from the Project Among African Americans to Explore Risks for Schizophrenia (PAARTNERS;Aliyu et al 2006;Calkins et al 2010). AU parficipants were evaluated using the Penn Computerized Neurocognifive Battery (CNB), which encompasses several cognifive domains (Gur et al 2001;Calkins et al 2010).…”

Neurocognitive Growth Charting in Psychosis Spectrum Youths

“…[16][17][18] We have implemented a computerized neurocognitive battery (CNB) 19 in large-scale studies, [20][21][22][23] measuring performance in executive, episodic memory, complex cognition, social cognition, and sensorimotor speed domains. Deficits prominent in schizophrenia are heritable and are milder in unaffected family members.…”

“…Deficits prominent in schizophrenia are heritable and are milder in unaffected family members. 20,21,[23][24][25] The sensitivity and validity of the CNB was established in a developmental cohort of 3500 Philadelphia Neurodevelopmental Cohort participants in whom we documented age and sex effects on performance. 26 To generate neurocognitive age growth charts, indices are calculated reflecting predicted age based on performance.…”