Mortality, Causes of Death, and Predictors of Death among Patients On and Off Opioid Agonist Treatment: Results from a 19-Year Cohort Study

Abstract

<b><i>Background:</i></b> Mortality is increased among people with opioid use disorder but reduced while on opioid agonist treatment (OAT). However, the impact of patient and treatment characteristics on mortality and causes of death is insufficiently studied. <b><i>Objectives:</i></b> The objective of this study was to explore mortality and causes of death and examine the impact of patient and treatment characteristics on mortality in an OAT cohort with high retention in treatment. <b><i>Methods:</i></b> <i>Design</i>: longitudinal cohort study. <i>Setting</i>: Norway. <i>Observation period</i>: time from OAT start as of 1998 until death or end of 2016, 2,508 person-years (PY) in total. <i>Sample</i>: 200 persons starting OAT 1998–2007. <i>Data sources</i>: hospital records, interviews, the Norwegian Cause of Death Registry, Statistics Norway. <b><i>Results:</i></b> Retention: 86.4% of the observation period was on OAT, 9.0% off, 4.6% unknown OAT status. All-cause crude mortality rate per 100 PY during the whole observation period was 1.64 (95% CI: 1.19–2.20), for deaths of somatic cause 0.88 (0.56–1.31), for drug-induced deaths 0.44 (0.23–0.76), and traumatic deaths 0.24 (0.10–0.50). Off-versus-on-OAT all-cause mortality ratio was 2.31 (1.00–4.85). On OAT, 58% of the deaths were of somatic cause and 21% drug-induced; off OAT, 38% of somatic cause and 50% drug-induced. Increasing baseline age and rate of somatic hospital treatment episodes were independently associated with <i>increased</i> all-cause mortality risk, while increasing rate of in-patient psychiatric treatment episodes was associated with <i>reduced</i> risk. Increasing duration of nicotine and cannabis use and alcohol dependence as well as increasing severity of polydrug use were associated with increased all-cause and somatic mortality adjusted for age and sex. <b><i>Conclusion:</i></b> The long observation period made it possible to demonstrate the importance of long-term retention in OAT to reduce mortality. Further, the preponderance of somatic and reduction of drug-induced causes of death during OAT underlines the need for follow-up of chronic diseases and health-promoting lifestyle changes. These findings add to the knowledge about long-term OAT effects, not least in ageing OAT populations.

Mortality and alcohol‐related morbidity in patients with delirium tremens, alcohol withdrawal state or alcohol dependence in Norway: A register‐based prospective cohort study

“…This finding indicates that mortality is not only an issue around the time of the DT episode, but very much so in the months and years thereafter. The crude annual mortality rate in DT patients in our study exceeds the average mortality rate among, for instance, male cancer patients [26] or injecting heroin users [27] in Norway.…”

Change in self-reported somatic symptoms among patients in opioid maintenance treatment from baseline to 1-year follow-up

“…Conversely, treatment may positively affect quality of life [ 52 ]. Efforts to prevent and strengthen early diagnosis, treatment, and follow-up of chronic somatic disorders are important to reduce premature mortality and increase quality of life, thereby providing a good treatment experience [ 14 ]. In terms of oral health and gastrointestinal well-being, treatment providers should not overlook such “ordinary” symptoms and regularly follow-up on such complaints to increase the well-being of patients.…”

Patients’ satisfaction with heroin-assisted treatment: a qualitative study

“…A large body of research in the OUD field demonstrates that the risk of overdose is high before entering treatment and even greater when treatment is terminated [ 6 ]. Around 1 out of 10 OAT patients in Norway terminate their treatment annually [ 7 ], while a recent systematic review found that between 20 and 84% of OAT patients remain in treatment [ 8 ].…”