Opioid agonist treatment status preceding buprenorphine-related death in Finland

Background: Buprenorphine is the most common abused opioid and single drug causing fatal poisonings in Finland. In this nationwide retrospective study, we investigated for the first time in Finland the role of opioid agonist treatment (OAT) preceding buprenorphine-related deaths.

Methods: We investigated all deaths (N = 604) between 2018 and 2020 with a buprenorphine or norbuprenorphine finding in post-mortem toxicology and with a known drug abuse history or concomitant findings of illegal drugs. In the absence of a nationwide register on OAT, we sent an inquiry to substance abuse service units offering OAT, asking whether the deceased had received OAT within a year before death. For those who had received treatment, we requested patient records containing detailed information on the treatment provided.

Results: Our preliminary results show that approximately 10% of the deceased had received OAT within a year before death. Of those receiving OAT, many had ceased OAT self-willingly and without following recommended tapering by health professionals. The cause of death was poisoning with buprenorphine implicated in about half of the deaths of OAT patients, and the other half were due to other causes of death. Concomitant abuse of other depressant substances, especially benzodiazepines, was found in more than 90% of cases. No information was available on the possible medical treatment of those individuals who did not receive OAT.

Conclusion: Buprenorphine-related deaths in Finland occur mainly outside of OAT. Concomitant abuse of other drugs and OAT cessation may increase the risk of premature death. In order to prevent buprenorphine deaths, drug users' access to and commitment to OAT should be improved and they should be better informed about unsafe drug use patterns.