Background: Bone pain is one of the most common presentations of multiple myeloma and nearly all patients have skeletal involvement in the course of disease. Consequently, many patients require narcotics for symptom management at the time of diagnosis but the long term impact of MM treatment on pain control remains uncertain. With the advent of combination therapy for MM with novel agents followed by transplant and then maintenance therapy, clinical response is nearly universal and greater than 30% of patients achieve a serologic complete response. Therefore, we examined the impact of modern myeloma-directed therapy and high response rates on the use of narcotics up to 1 year after transplant in this group of patients.
Methods: A retrospective review of data collected from the Rutgers-CINJ database was conducted. All patients who received induction inducing therapy (e.g. bortezomib, lenalidomide and dexamethasone or cyclophosphamide, bortezomib and dexamethasone) followed by high dose melphalan and autologous stem cell transplant (ASCT) and who had adequate post-transplant follow up (at least 100 days) were included. Morphine use was assessed at the time of transplant and at follow-up visits. All opiates (e.g. oxycodone, fentanyl, MS contin, etc.) where converted to morphine equivalents/day (ME/day) and recorded. Treatment responses were determined based on the International Myeloma Working Group Response Criteria. We compared the incidence and amount of narcotic use over time using one-way analysis of variance (ANOVA) and Dunn's multiple-comparison test.
Results: 189 patients were included in the analysis. 38% were using opiates at the time of transplant. At 100 days post-transplant 35.5% were using opiates and at 1 year post transplant 30.9% were using opiates (p=0.04) . Average opiate use was 74.1 ME/day (95% CI: 55.2 to 92.9), 69.45 ME/day (95% CI: 50.5 to 88.3), and 70.78 ME/day (95% CI: 43.5 to 98) for each of the aforementioned time points (p=0.088) (Figure 1). For example, 74 ME/day would be equal to approximately 50 mg of Oxycodone daily.
74 patients were active opiate users at the time of transplant (Table 1).
Response to myeloma treatment (remission, progression, relapse) was not different in opiate-using patients at the time of transplant or at 100 days and 1 year after transplant (Table 2).
Conclusion: Early studies from the 1960's reported on the rapid reduction of bone pain in treatment responsive patients with MM (Hogstrata et al.). Recently, treatment modalities for MM have significantly improved, leading to markedly increased remission rates (>90%), progression-free and overall survival. With dramatically increased serologic responses, one would hypothesize that there would be a decline in pain and a subsequent decrease in opiate use. However, in this retrospective chart review we found that 30% of multiple myeloma patients continued to use opiates following transplant and that ongoing use of opiates appeared to be independent of clinical response. Interestingly, at the time of transplant active opiate users had a CR of 27.2% while the non-opiate using patients had a CR of 13.3%. Although there was a slight decline in the number of opiate users at the 1 year follow up, 33% of opiate users continued at their original level of opiate use and 22% increased their opiate use at 1 year post ASCT.
Persistent long term use of opiates is of particular concern given that the survival of patients with MM has significantly improved with the use of novel agents and autologous transplant with an increasing number of patients surviving 10 years or more. In patients who have achieved an excellent response (e.g. serologic CR and negative PET scan), ongoing narcotic use should be addressed at each visit and other advanced pain management techniques should be considered.
No relevant conflicts of interest to declare.
