Evidence for the early clinical relevance of hallucinatory-delusional states in the general population

Nuevo R, Van Os J, Arango C, Chatterji S, Ayuso-Mateos JL. Evidence for the early clinical relevance of hallucinatory-delusional states in the general population. Objective: To analyze, in a general population sample, clustering of delusional and hallucinatory experiences in relation to environmental exposures and clinical parameters. Method: General population-based household surveys of randomly selected adults between 18 and 65years of age were carried out. Setting: 52 countries participating in the World Health Organization's World Health Survey were included. Participants: 225842 subjects (55.6% women), from nationally representative samples, with an individual response rate of 98.5% within households participated. Results: Compared with isolated delusions and hallucinations, co-occurrence of the two phenomena was associated with poorer outcome including worse general health and functioning status (OR=0.93; 95% CI: 0.920.93), greater severity of symptoms (OR=2.5 95% CI: 2.03.0), higher probability of lifetime diagnosis of psychotic disorder (OR=12.9; 95% CI: 11.514.4), lifetime treatment for psychotic disorder (OR=19.7; 95% CI: 17.322.5), and depression during the last 12months (OR=11.6; 95% CI: 10.912.4). Co-occurrence was also associated with adversity and hearing problems (OR=2.0; 95% CI: 1.82.3). Conclusion: The results suggest that the co-occurrence of hallucinations and delusions in populations is not random but instead can be seen, compared with either phenomenon in isolation, as the result of more etiologic loading leading to a more severe clinical state.