The Association Between Buprenorphine/Naloxone and All-Cause Mortality in the United Kingdom (UK): An Interim Report

• Published in: Value in health 2017-10, Vol.20 (9), p.A716
• Main Authors: Auriacombe, M, Apelt, SM, Scherbaum, N, Mankabady, B
• Format: Article
• Language: English
• Subjects: Analgesics; Buprenorphine; Comorbidity; Comparative studies; Drugs; Mental disorders; Mental health; Methadone; Mortality; Naloxone; Oral administration; Patients; Prescription drugs; Substance use disorder
• ISSN: 1098-3015; 1524-4733
• DOI: 10.1016/j.jval.2017.08.1907

OBJECTIVES: The main objectives were: (1) characterize patients in the UK who received a prescription for buprenorphine/naloxone (BUP/NLX), buprenorphine alone, or methadone; and (2) assess all-cause mortality rates in these medication groups. METHODS: In this retrospective observational study, electronic records from The Health Improvement Network (THIN) database were searched for BUP/ NLX (sublingual tablet), buprenorphine (sublingual tablet), and methadone prescriptions issued between l-Jan-2007 and 31-Dec-2015. Mortality rates were analyzed in the overall population (BUP/NLX=964; buprenorphine=1865; methadone=6363). Two designs were used for comparative analyses: (1) new-user cohort, defined as patients (case subjects) with ≥1 year enrollment before first prescription (BUP/ NLX=615; buprenorphine=1011; methadone=2723); and (2) case-control design, nested within the new-user cohort with ≤5 matched-controls randomly sampled for each case subject. Cox regression was used to analyze hazard ratios (HRs) for mortality in the new-user cohort; logistic regression was used to analyze odds ratios (ORs) for exposure to study drug (defined as "current", "recent", or "past or never") in the nested case-control cohort. Analyses were adjusted for baseline covariates, and all P-values were two-sided. RESULTS: Most of the 964 BUP/NLX users were male (70.5%) and aged 20-49 years (94.2%). Mortality rates per 1000 person-year (95% CI) were: BUP/NLX, 5.29 (3.02-8.58); buprenorphine, 10.79 (8.50-13.50); methadone, 28.34 (26.18-30.63). In the new-user cohort, HRs for all-cause mortality for buprenorphine and methadone relative to BUP/NLX were 1.05 (P=0.90) and 4.47 (p