Widely used as a substitute for opiates in France, buprenorphine would divide the risk of mortality by six in patients followed in primary care according to a new French retrospective study published in the Lancet Public Health .
There are limited data regarding the association between opioid agonist therapy (OAT) and reduction in all-cause mortality in the setting of widespread buprenorphine use. The objective of this study was to study the risk of mortality in French patients followed in primary care and under OAT, depending on the duration of treatment (with or without interruption).
Method
This population-based retrospective cohort study was based on the National Health Data System (SNDS). Were included patients aged 15 years and over who started treatment with an opioid agonist (OAT) between 1is January 2010 and December 31, 2022 and having received at least two consecutive prescriptions for opioid agonists. Covariates, extracted from the SNDS, included age, sex, deprivation index, medical comorbidities, psychiatric disorders and concomitant treatments. The primary endpoint was all-cause mortality at 1 year ; secondary endpoints were all-cause mortality at 2, 5, and 7 years and specific mortality. Multivariate Cox models, taking into account exposure to treatment as a function of time (under TAO vs excluding TAO), were used to evaluate the association between TAO and mortality.
Results
The study involved 175,191 people on opioid substitution treatment (OST), including 131,444 (75.0%) men and 43,747 (25.0%) women. The median duration of follow-up was 3,320 days. At baseline, most patients were receiving buprenorphine (65.2%) or a buprenorphine-naloxone combination (3.4%). Use of opioid substitution therapy (OST) was associated with a lower risk of all-cause mortality at 1 year and this association persisted at 2 years. OST was also associated with lower mortality from certain causes, including trauma or poisoning, drug-related deaths, accidental overdoses, infectious causes, and suicide, with similar trends over time. The association was particularly strong for buprenorphine, which had a 6-fold lower risk of death from all causes at 1 year.
Interpretation
In this large national cohort of participants newly enrolled in opioid substitution therapy, there was therefore a significant reduction in the risk of treatment-associated all-cause mortality. This association was particularly marked for buprenorphine. Funded by the Epi-phare scientific interest group and led in particular by Professor Julie Dupouy, vice-president of the national college of general practitioners, teachers and researchers from the universities of Toulouse and Bordeaux, this study is a real argument in favor of easier access to this opioid substitution product that is buprenorphine. Remember that in France, it is the reference treatment and its primary prescription can be made by any general practitioner (even without specific training), while treatment with methadone can only be initiated in a specialized center (Csapa, Caarud, hospital department, etc.) and requires regular monitoring.
• Topioid agonist treatment and risk of mortality in primary care in France: a national retrospective cohort study, Professor Julie Dupouy, MD PhD Send an email to julie.dupouy@dumg-toulouse.fr∙Vladimir Druel, doctor of medicine∙Doctor of medicine∙Pr Antoine Pariente, MD PhD∙Maryse Lapeyre-Mestre, MD PhD; The Lancet Volume 11, Number 7 E449-E456 July 2026.
