S1005 The Implications of Chronic Opioid Use on Post-Transplant Clinical Outcomes: A Systematic Review and Meta-Analysis

Abstract

INTRODUCTION: Based on current literature, pre-transplant chronic opioid use (COU) for analgesia is highly prevalent among patients awaiting solid-organ transplant. However, there are very few large-scale studies on the effect of COU on post-transplant outcomes. We conducted a systematic review and meta-analysis to evaluate the impact of pre-transplant COU on solid-organ transplantation clinical outcomes. METHODS: A comprehensive literature review was conducted by searching the PubMed, Ovid Medline, Embase, Web of Science, and Cochrane databases from inception to April 2020 to identify all studies that evaluated the impact of pre-transplant COU on post-transplant clinical outcomes. COU was defined as >3 months of consecutive opioid use entering transplant listing. The search included studies regarding heart, lung, kidney, and liver transplantation (Figure 1). Our primary outcome was all-cause mortality, and secondary outcomes were graft failure and the one-year readmission rate. A random-effect model was used to estimate the pooled hazard ratios (HR) or odds ratios (OR) of our outcomes. RESULTS: Nine retrospective studies involving 166,765 patients were included in the primary meta-analysis. The all-cause mortality rate was significantly higher in patients who were on chronic opioids preceding transplant compared to those who were not (HR 1.42; 95% CI 1.34-1.50). The included studies demonstrated low heterogeneity (Figure 2). Additionally, COU patients had an increased risk of graft failure compared to non-COU patients (HR 1.26; 95% CI (1.13–1.40) (Figure 3). With regards to the one-year readmission rates, only three studies were included. There was no statistically significant difference in the readmission rate between the two groups (HR 1.78; 95% CI (0.87–3.63). The three studies had high heterogeneity. CONCLUSION: This study demonstrates that pre-transplant COU in solid-organ transplant patients is associated with an increased risk of all-cause mortality and graft failure. Pre-transplant COU may be a surrogate for comorbidities causing chronic pain or psychosocial traits that can contribute to non-compliance post-transplant. These potential risk factors may explain the increased risk of poor outcomes post-transplant. Therefore, a careful evaluation of opioid use patterns and consideration of alternative analgesic strategies is warranted in this population to lessen the reliance on opioid use and associated adverse outcomes.Figure 1.: Literature review process.Figure 2.: Forest plot of mortality.Figure 3.: Forest plot of graft loss.