Spatial distribution of psychotic disorders in an urban area of France: an ecological study

Abstract

Previous analyses of neighbourhood variations of non-affective psychotic disorders (NAPD) have focused mainly on incidence. However, prevalence studies provide important insights on factors associated with disease evolution as well as for healthcare resource allocation. This study aimed to investigate the distribution of prevalent NAPD cases in an urban area in France. The number of cases in each neighbourhood was modelled as a function of potential confounders and ecological variables, namely: migrant density, economic deprivation and social fragmentation. This was modelled using statistical models of increasing complexity: frequentist models (using Poisson and negative binomial regressions), and several Bayesian models. For each model, assumptions validity were checked and compared as to how this fitted to the data, in order to test for possible spatial variation in prevalence. Data showed significant overdispersion (invalidating the Poisson regression model) and residual autocorrelation (suggesting the need to use Bayesian models). The best Bayesian model was Leroux’s model (i.e. a model with both strong correlation between neighbouring areas and weaker correlation between areas further apart), with economic deprivation as an explanatory variable (OR = 1.13, 95% CI [1.02–1.25]). In comparison with frequentist methods, the Bayesian model showed a better fit. The number of cases showed non-random spatial distribution and was linked to economic deprivation.

Neighbourhood deprivation is positively associated with detection of the ultra-high risk (UHR) state for psychosis in South East London

“…It is possible that the occurrence of the UHR state displays important variation by neighbourhood of residence ( Oher et al, 2014 ), for three reasons. Firstly, it would be consistent with evidence for neighbourhood variation in the incidence of psychosis( Faris and Dunham, 1939 , Kirkbride et al, 2016b , Pignon et al, 2016 , Silver et al, 2002 ). For example, in a recent study based on data from early intervention services in the East of England, Kirkbride et al (2016b) reported positive associations between psychosis incidence and both neighbourhood population density and neighbourhood deprivation.…”

Relationship between incidence and prevalence in psychotic disorders: An incidence–prevalence–mortality model

“…The social drift phenomenon could for instance explain an increased migration of subjects with psychotic disorders to economically deprived areas (Ngamini Ngui et al, ). In a precedent study on the same catchment area, we showed that patients with psychotic disorders lived in more deprived neighbourhoods (Pignon et al, ).…”

“…The catchment area included two adjacent cities in the southeast of Paris (France): Créteil and Maisons‐Alfort (total adult population 109,397 people). The catchment area is a densely populated area, with 8,568 inhabitants per square kilometre, with a high migrant density (migrants represent 19.8% of the population), and a high unemployment rate (12.6%) (Pignon et al, ; Szöke et al, ).…”

Étude pilote des relations entre manifestations psychotiques et environnement de résidence

“…Les représentations étaient qualifiées au travers de 14 items regroupés en 3 dimensions : (i) crimes et actes de vandalisme, (ii) environnement social incluant la réputation du quartier et (iii) environnement construit. Il apparaît que les individus dont les représentations du quartier (Pignon et al, 2016). Les relations avec le niveau de fragmentation sociale (pourcentage de résidents dans le quartier depuis moins de 2 ans, part de personnes vivant seules) et avec la part de personnes nées à l'étranger ou étrangères ne sont, par contre, pas significatives.…”

“…L'hypothèse serait que ces manifestations psychotiques atténuées sont en partie influencées par des facteurs individuels et par des caractéristiques contextuelles liées à l'environnement de vie. Après l'étude historique de Faris et Dunham à Chicago démontrant qu'il n'y a pas d'homogénéité dans la distribution spatiale des troubles psychotiques (Faris & Dunham, 1939), il a fallu attendre le début des années 2000 pour que les travaux de recherche sur les facteurs de risques individuels et contextuels des troubles Octobre 2020 Longo Antoine 3/16 mentaux s'intensifient (Kirkbride et al, 2014 ;Pignon et al, 2016 ;Weich et al, 2003).…”