Abstract
Aims: To examine and compare mortality rates in patients treated with oral and implant naltrexone. Design: A retrospective cohort study . Setting: A community not-for-profit drug treatment clinic. Participants: Patients treated with oral naltrexone (n = 2155, 17 207 patient years) and implant naltrexone (n=2389, 11 678 patient years) for problematic opiate use between August 1997 and December 2009. Measurements: Crude, gender, age, treatment period and cause specific mortality rates were calculated using data obtained from the National Death Index. Findings: Crude mortality rates for patients treated with oral naltrexone (8.78 deaths per 1 000 patient years (ptpy), 95%CI: 7.38 to 10.17) were significant different to those treated with implant naltrexone (6.59ptpy, 95%CI: 5.13 to 8.06) (p=0.0339). In the first 4 months following treatment differences in the two groups were particularly apparent, with a mortality rate of 26.28ptpy in patients treated with oral naltrexone compared to 7.34ptpy in patients treated with implant naltrexone (p=0.0003). Differences in initial mortality rates following treatment were predominately associated with high rate of opiate overdoses in oral naltrexone patients in the first 4 months following treatment (17.22ptpy compared with 0.67ptpy in implant naltrexone patients) (p<0.0001). Conclusions: The use of implant naltrexone can reduce all-cause mortality and opiate overdose during the first four months following treatment as compared with patients treated with oral naltrexone.