Spatial distribution of maxillofacial injuries caused by urban violence: An ecological analysis to identify high-risk areas.

OBJECTIVES: To investigate the spatial and spatial-temporal distribution of oral and maxillofacial injuries caused by urban violence, as well as to identify underlying disparities at regional level through a geostatistical approach.

METHODS: This was a historical ecological cohort study of trauma cases caused by urban violence using aggregate data from victims assisted in a Brazilian medical-forensic service between January 2012 and December 2015. The longitudinal patterns of change observed in each geographic area (neighbourhoods) were evaluated using the finite mixture model (FMM). The spatial autocorrelation of events was investigated using the Getis-Ord Indicator (Gi*) to identify significant hot and cold spatial clusters. With a spatial regression model, it was also found when socioeconomic variables, residential infrastructure and neighbourhood infrastructure were associated with high incidence rates. The significance level was set at P ≤ 0.05.

RESULTS: The finite mixture model revealed three different patterns of longitudinal trajectory of the incidence of oral and maxillofacial trauma caused by urban violence (TP1 to TP3, P < 0.05). TP1 was characterized by an incidence that remained stable and high over time, comprising 17.4% of the city's neighbourhoods. In TP2, it was observed that the incidence was moderate, with a slightly increasing trend in the last year evaluated, representing around 41.8% of the sample. In contrast, in TP3, it was found that the incidence was relatively low and remained stable over time, accounting for about 40.8% of the sample. The Getis-Ord (Gi*) statistic identified significant high-risk clusters in the western (P < 0.05), southern (P < 0.05), and eastern regions (P < 0.05) and low risk in the northern region (P < 0.05). The spatial regression model indicated significant association between areas with unfavourable socioeconomic conditions and higher incidence of events (β = 0.178, SE = 0.046, P < 0.001).

CONCLUSIONS: Clusters demarcating areas with high socio-spatial vulnerability for urban violence and oral and maxillofacial injuries were identified. The findings highlight the need to improve living conditions in segregated urban areas and develop intersectoral actions to improve living conditions, employment, public safety, social support, health care and prevention.