This article is more than 5 years old. Information may no longer be current.

Some facets of impaired community functioning in schizophrenia are familial

Impaired community functioning in schizophrenia followed different developmental trajectories; however, researchers found that impairments in social activity and functioning in school or work were familial.

“Schizophrenia affects approximately 1% of the population. Mostly known for psychotic features and neuropsychological deficits, the disorder is also characterized by persistent impairment in community functioning,” Eva Velthorst, PhD, of Icahn School of Medicine at Mount Sinai, New York, and colleagues wrote. “The few studies that investigated community functioning before illness onset have found subtle functional deficiencies in early functional development followed by more severe impairments during late adolescence.”

Researchers evaluated 723,316 Israeli male adolescents, of which 3,929 were hospitalized for schizophrenia, to assess social activity, independent behavior and school or work functioning before first hospitalization and whether these domains of community functioning were familial. Sibling analysis included 338,550 sibling pairs, of which 1,659 were hospitalized with schizophrenia. Study participants were followed for a maximum of 25.4 years.

Among participants with schizophrenia, impairments in social activity and functioning in school or work were observed up to 15 years before hospitalization.

Independent behavior appeared preserved until a few years before first admission, according to researchers.

Differences between cases and controls regarding social activity were progressively greater for participants admitted closer to time of testing (P < .001).

Unaffected siblings had small impairments in social activity (P < .001) and functioning in work or school (P < .001), compared with controls.

Group familial correlations were high for social activity and functioning in work or school, but not for independent behavior.

Community functioning impairments in siblings did not progressively increase and were unrelated to their affected sibling’s illness onset.

“Overall, our findings indicate that examining community functioning as one global concept oversimplifies the complex nature of functional impairment and that different domains follow distinct trajectories in the years before first hospitalization. It is hoped that reducing the heterogeneity of the behavioral phenotype by parsing community functioning into separate domains will enable better identification of risk factors associated with schizophrenia,” Velthorst and colleagues wrote. “Genetic studies are needed to further disentangle familiality from heritability, to further understand the potentially unique pathophysiologic pathways of these domains, and to determine whether functional anomalies make valuable candidates for sociogenetic research in schizophrenia.” – by Amanda Oldt

Disclosure: The researchers report no relevant financial disclosures.