Urban overdose hotspots: a 12-month prospective study in Dublin ambulance services

Opioid overdose (OD) is the primary cause of death among drug users globally. Personal and social determinants of overdose have been studied before, but the environmental factors lacked research attention. Area deprivation or presence of addiction clinics may contribute to overdose.

The objective of the study is to examine the baseline incidence of all new ODs in an ambulance service and their relationship with urban deprivation and presence of addiction services.

A prospective chart review of prehospital advanced life support patients was performed on confirmed OD calls. Demographic, geographic, and clinical information, that is, presentation, treatment, and outcomes, was collected for each call. The census data were used to calculate deprivation. Geographical information software mapped the urban deprivation and addiction services against the overdose locations.

There were 469 overdoses, 13 of which were fatal; most were male (80%), of a young age (32 years), with a high rate of repeated overdoses (26%) and common polydrug use (9.6%). Most occurred in daytime (275) and on the streets (212). Overdoses were more likely in more affluent areas (r = .15; P < .05) and in a 1000-m radius of addiction services. Residential overdoses were in more deprived areas than street overdoses (mean difference, 7.8; t170 = 3.99; P < .001). Street overdoses were more common in the city center than suburbs (χ(2)(1) = 33.04; P < .001).

The identified clusters of increased incidence-urban overdose hotspots-suggest a link between environment characteristics and overdoses. This highlights a need to establish overdose education and naloxone distribution in the overdose hotspots.