Social Fragmentation and Schizophrenia: A Systematic Review.

Abstract

Objective: Accumulating evidence implicates social context in the etiology of psychosis. One important line of epidemiologic research pointing to a potentially causal role of social context pertains to what is termed social fragmentation. The authors conducted a systematic review of the relationship between area-level social fragmentation and psychosis.Data Sources: Three databases (MEDLINE, PsycINFO, and Web of Science) were searched from inception to May 2, 2021. There were no language restrictions. Search terms were those that identify the area-level orientation, social fragmentation, sample, and outcome.Study Selection: Inclusion criteria were the following: (1) social environment measured at the area level with (2) psychosis outcomes (incidence rates, prevalence of psychosis or schizophrenia, age at onset of psychosis, psychotic symptom severity, and duration of untreated psychosis). In total, 579 research articles were identified, and 19 were eligible to be included in this systematic review.Data Extraction: Two reviewers independently screened, extracted data from, and coded all articles.Results: Evidence from 14 of 19 articles indicates that area-level characteristics reflecting social fragmentation are associated with higher psychosis rates and other outcomes of psychosis even after controlling for other area-level characteristics including deprivation, social capital, race/ethnicity, and urbanicity and individual-level characteristics including age, sex, migrant status, and socioeconomic status.Conclusions: In conclusion, this review finds evidence that measures of area-level social fragmentation are associated with higher psychosis rates. Further research into mechanisms is needed to better characterize this association.