Lifetime prevalence of psychotic-like experiences and associated factors in Chile

Psychotic-like experiences (PLEs), which include hallucinations and delusional experiences, are usually present in healthy populations, and their persistence, quality, and severity are associated with the development of psychiatric diseases, including schizophrenia and other poor psychosocial outcomes. Urbanicity, depression, and other psychosocial stressors have been associated with PLEs. However, evidence of PLEs in Latin American (LATAM) countries is still scarce, and there are no studies about PLEs in Chile. The main aim of this study is to describe the prevalence of PLEs in a nationally representative sample according to other social determinants of health.

The last results of the Chilean National Health Survey (ENS 2016-2017) were analyzed. PLEs were obtained from the Composite International Diagnostic Interview (CIDI) 3.0 and included in this survey. Other psychosocial variables (age, sex, educational level, financial stress, depressive symptoms, and urbanicity) were also included for further analysis. Exclusion criteria were (1) >  = 65 and < 18 years old, and (2) previous diagnosis or treatment for schizophrenia or bipolar disorder. Descriptive statistics were used to describe data, and Poisson regression models were performed to weight variables and find psychosocial correlations with PLEs.

2095 subjects were considered for this study (women 62.9% and mean age = 42.5, SD = 13.5). The lifetime prevalence of the PLEs (> = 1 PLE) in Chile was 12.9%. Visual hallucinations were the most common PLE (9.6%), and ideas of reference were the least common (0.4%). The Poisson regression model showed a higher prevalence of PLEs in the Gran Concepción conurbation (OR = 2.56) and Gran Valparaíso conurbation (OR = 1.69) compared with non-big cities. On the other hand, the 18-24 year group had higher PLEs prevalence compared to other age groups. No correlations were found with educational status, financial stress, or depressive symptoms.

A relatively high prevalence of PLEs was found in the Chilean general population, particularly in youth living in large urban areas (Gran Valparaíso and Gran Concepción), which is compatible with previous research. Considering that there were no correlations between low educational level and financial or depressive symptoms, it is necessary to have more studies that correlate other urban relevant variables, such as natural disasters, drug consumption, and domestic or neighborhood violence.