Background The incidence of fatal opioid overdoses is a growing and significant health concern in developed countries. We aimed to describe demographic attributes and healthcare utilisation of individuals who died due to opioid overdose in Wales using routine data. This research is a part of the TIME study on the feasibility of using Take-Home Naloxone kits to reduce deaths related to opioid overdose.

Methods A retrospective cross-sectional analysis was conducted for data from January 1^st2015 to November 30^th2021. Anonymised individual-level records from six Welsh routine data sources: Annual District Death Extract (ADDE); the Emergency Department Data Set (EDDS); the Patient Episode Database for Wales (PEDW); the Critical Care Data Set (CCDS); Substance misuse Dataset (SMDS) and the Welsh Longitudinal General Practice (WLGP) were linked within the SAIL databank. Residents in Wales aged 18 or above within the study window were assessed, censoring at final date of residency in Wales. Deaths were classified as related to opioid overdose (or not) using ICD-10 coding framework, and healthcare events identified within 12 months of study end dates. Composite measures of healthcare utilisation due to opioid overdose (or otherwise) were derived.

Results Demographic characteristics: 1,105 deaths related to opioid overdose. Predominantly male (n=785, 71%), middle-aged (25% opioid overdoses aged 46-55; mean age: 44.3 years) and resident in the most deprived areas (40%). 50% of deaths were classified as accidental; heroin was explicitly noted in 60% of cases. Healthcare utilisation events 1 year prior to deaths: Opioid overdose related: 144 (13%) cases in EDDS, 56 (5%) cases in PEDW and 165 (15%) cases in SMDS. All other events: 682 (62%) cases in EDDS; 483 (44%) cases in PEDW; 118 (11%) cases in CCDS; 243 (22%) cases in SMDS. No healthcare event recorded: Over a quarter of cases (n=307, 28%) had no recorded healthcare event, whether related to opioid overdose or other events.

Conclusion People who died with an opioid related cause were predominantly male, middle-aged, and more likely to live in relatively deprived areas. Healthcare utilisation for opioid-related causes in 12 months prior to death was generally low. 28% of decedents had no recorded contact at all with acute care providers.