Association Between Prescription Opioid Therapy for Noncancer Pain and Hepatitis C Virus Seroconversion

Abstract

IMPORTANCE Initiation of injection drug use may be more frequent among people dispensed prescription opioid therapy for noncancer pain, potentially increasing the risk of hepatitis C virus (HCV) acquisition.OBJECTIVE To assess the association between medically dispensed long-term prescription opioid therapy for noncancer pain and HCV seroconversion among individuals who were initially injection drug use-naive. DESIGN, SETTING, AND PARTICIPANTSA population-based, retrospective cohort study of individuals tested for HCV in British Columbia, Canada, with linkage to outpatient pharmacy dispensations, was conducted. Individuals with an initial HCV-negative test result followed by 1 additional test between January 1, 2000, and December 31, 2017, and who had no history of substance use at baseline (first HCV-negative test), were included. Participants were followed up from baseline to the last HCV-negative test or estimated date of seroconversion (midpoint between HCV-positive and the preceding HCV-negative test).EXPOSURES Episodes of prescription opioid use for noncancer pain were defined as acute (<90 days) or long-term (Ն90 days). Prescription opioid exposure status (long-term vs prescription opioid-naive/acute) was treated as time-varying in survival analyses. In secondary analyses, longterm exposure was stratified by intensity of use (chronic vs. episodic) and by average daily dose in morphine equivalents (MEQ). MAIN OUTCOMES AND MEASURESMultivariable Cox regression models were used to assess the association between time-varying prescription opioid status and HCV seroconversion. RESULTS A total of 382 478 individuals who had more than 1 HCV test were included, of whom more than half were female (224 373 [58.7%]), born before 1974 (201 944 [52.8%]), and younger than 35 years at baseline (196 298 [53.9%]). Participants were followed up for 2 057 668 person-years and 1947 HCV seroconversions occurred. Of the participants, 41 755 people (10.9%) were exposed to long-term prescription opioid therapy at baseline or during follow-up. The HCV seroconversion rate per 1000 person-years was 0.8 among the individuals who were prescription opioid-naive/acute (1489 of 1947 [76.5%] seroconversions; 0.4% seroconverted within 5 years) and 2.1 with long-term prescription opioid therapy (458 of 1947 [23.5%] seroconversions; 1.1% seroconverted within 5 years). In multivariable analysis, exposure to long-term prescription opioid therapy was associated with a 3.2-fold (95% CI, 2.9-3.6) higher risk of HCV seroconversion (vs prescription opioid-naive/acute). In separate Cox models, long-term chronic use was associated with a 4.7-fold (continued) Key Points Question Is long-term prescription opioid therapy for noncancer pain associated with hepatitis C virus (HCV) seroconversion among individuals who initially had no history of injection drug use? Findings In this cohort study of 382 478 individuals who had a baseline negative HCV test followed by at least 1 additional test, long-term prescription opioid therapy among those who were initi...

Association Between Opioid-Related Mortality and History of Surgical Procedure: A Population-Based Case-Control Study

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“…Controls were excluded if they died of HIV- or alcohol-related death; 2 disorders that may be associated with higher rates of opioid use than the general population, which could confound the outcome. 24 A sensitivity analysis was conducted to determine whether including controls with HIV- or alcohol-related deaths would change the results.…”

“…Opioid-related mortality was identified using a modified version of an algorithm developed by the Centers for Disease Control and Prevention plus heroin (Supplemental Appendix 1, see http://links.lww.com/AOSO/A314 ). 5 , 24 The algorithm defines opioid-related mortality as death directly related to opioid poisoning, with at least one opioid contributing to multiple causes of death. 5 , 24 The algorithm has a positive predictive value of 90% and a sensitivity of 75%.…”

“… 5 , 24 The algorithm defines opioid-related mortality as death directly related to opioid poisoning, with at least one opioid contributing to multiple causes of death. 5 , 24 The algorithm has a positive predictive value of 90% and a sensitivity of 75%. 5 , 24 …”

Hybrid model for precise hepatitis-C classification using improved random forest and SVM method

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