The incidence of non-affective psychotic disorders in Chile between 2005 and 2018: results from a national register of over 30 000 cases

Abstract

Background Evidence suggests the incidence of non-affective psychotic disorders (NAPDs) varies across persons and places, but data from the Global South is scarce. We aimed to estimate the treated incidence of NAPD in Chile, and variance by person, place and time. Methods We used national register data from Chile including all people, 10–65 years, with the first episode of NAPD (International Classification of Diseases, Tenth Revision: F20–F29) between 1 January 2005 and 29 August 2018. Denominators were estimated from Chilean National Census data. Our main outcome was treated incidence of NAPD and age group, sex, calendar year and regional-level population density, multidimensional poverty and latitude were exposures of interest. Results We identified 32 358 NAPD cases [12 136 (39.5%) women; median age-at-first-contact: 24 years (interquartile range 18–39 years)] during 171.1 million person-years [crude incidence: 18.9 per 100 000 person-years; 95% confidence interval (CI) 18.7–19.1]. Multilevel Poisson regression identified a strong age–sex interaction in incidence, with rates peaking in men (57.6 per 100 000 person-years; 95% CI 56.0–59.2) and women (29.5 per 100 000 person-years; 95% CI 28.4–30.7) between 15 and 19 years old. Rates also decreased (non-linearly) over time for women, but not men. We observed a non-linear association with multidimensional poverty and latitude, with the highest rates in the poorest regions and those immediately south of Santiago; no association with regional population density was observed. Conclusion Our findings inform the aetiology of NAPDs, replicating typical associations with age, sex and multidimensional poverty in a Global South context. The absence of association with population density suggests this risk may be context-dependent.

Urbanization and psychosis: an update of recent evidence

“…Studies from Brazil, Chile (LAMIC), and Australia, contrary to other studies, found no association between urbanicity and increased risk/ incidence of schizophrenia [29,30]. Studies involving schizophrenia patients show that the degree of urbanicity is associated with fewer social contacts but not with satisfaction with friendships [31].…”

“…Numerous studies have investigated the differences between urban and rural areas. Despite a few studies on urbanicity at birth/upbringing from LAMIC [20,24,25,27,29,30], much evidence still comes from high-income countries. It shows a positive association between urbanicity and risk for the development of psychotic disorder, in line with previous meta-analysis [5], but mixed results, especially for psychotic experiences.…”

“…All studies on area deprivation and association with schizophrenia or nonaffective psychosis, done in urban settings, have found positive associations [23,26,30,35 && ], especially deprivation at birth mediated through IQ [21]. Only a study from Northern Ireland found that Catholics had significantly higher total scores in higher own-group density areas than in lower own-group density areas, and protestants had no effect [36].…”

Consent, decisional capacity and guardianship in mental health research

“…MRI, neuropsychological assessments). To date, we have conducted studies on metabolic syndrome and healthy lifestyle 7 , neuroimaging 8 , treatment resistance 9 , social determinants of mental health 10 , epidemiology 11 , and public policies 6 , among other topics. This case report describes the potential benefits and associated challenges of conducting research in the context of a clinical practice in Latin America that works with vulnerable populations who have difficulties with decisional capacity.…”

The incidence of non-affective psychotic disorders in low and middle-income countries: a systematic review and meta-analysis

“…However, results from a cross-sectional survey of 42 Low and Middle Income Countries [LMICs] in the World Health Organization [WHO] World Health Survey [ 12 ], reported no consistent association between the prevalence of psychotic symptoms and contemporaneously-estimated rural or urban exposure. Although comparing such findings is difficult [ 13 ], recent evidence from a nationwide study in Chile [ 14 ] and multinational [ 15 ] incidence data from Europe and Brazil also found that regional deprivation was more strongly associated with the incidence of psychotic disorders than population density, usually considered a more direct marker of urbanicity; these studies suggest that different patterns of association between risk factors and psychosis may be present in different contexts. Unfortunately, evidence on the incidence of psychotic disorders—a central epidemiological cornerstone for understanding the burden, distribution, and aetiology of disease—from LMICs is scant.…”