Summary: Recently, the use of opioids to treat non-cancer chronic pains has become controversial. Some experts think such use is justified, while others believe that there is no additional benefit of opioid therapy. However, the problems with both these views are that they are not based on clinical data. There are practically no high-quality clinical studies regarding the opioid use in chronic pain treatment. Hence, to put an end to this debate, there is a need for large and well-designed clinical studies regarding the use of opioids to treat various chronic pain conditions.
One of the most pressing questions doctors are facing is whether to prescribe opioids to treat non-cancer chronic pains or not. However, experts say that most current views for and against opioids seem to be based on ideas and beliefs rather than on sound scientific findings. Thus, some doctors are strongly in favor of opioid use, while others are against such use. However, it seems that there is insufficient evidence from extensive studies for or against such use. Experts say there is an urgent need to carry out more extensive clinical studies. However, any such study regarding the use of opioids in chronic pain would need to enroll thousands of patients. This is because chronic pains occur due to many reasons, like autoimmune conditions, neuropathies, genetic disorders, and more. Further, there is a need to compare opioids with placebo and other non-opioid painkillers.
The problem with the existing data is that it is just too small. As a result, very few clinical studies have any practical significance in giving any results on the opioid use for chronic pain treatment. Furthermore, there appear to be some challenges in carrying out studies with opioids, as such studies are often terminated or withdrawn. Currently, no large-scale study is underway regarding opioid use for chronic pain. If we search PubMed for “opioid and chronic pain, “there are more than 16,000 research articles, yet very few of which are clinical studies. There is barely one study worth considering. It is a SPACE study done in 2018, and it studied the benefits of opioids over 12 months.
The study did not find opioids superior to other non-opioid therapies. But then, the study had some severe limitations. First, it mainly focused on low back pain and arthritis. These conditions tend to be chronic and progressive in many due to worsening bone health. Moreover, the study also included the use of tramadol in the non-opioid group. However, tramadol is a synthetic opioid with a potent pain-killing effect. Yet, another study found that barely one-fifth of patients benefited significantly from prolonged opioid therapy in chronic pain treatment. However, the study was based on a telephone survey, and thus, this kind of study has certain limitations2.
Similarly, an excellent study was published in the Cochrane review. The study found that opioid tapentadol was better for chronic pain that more commonly abused opioids like oxycodone. However, these findings have limited clinical relevance. To put it simply, there are not just enough studies to answer some of the very basic questions, like who will benefit more from opioids than other medications like NSAIDs. And even if doctors decide to move forward with opioid therapy, what opioid must be chosen for a specific kind of chronic pain? Further, there is a need to find out the role of opioids in the long term chronic pain treatment and management.
Even studies regarding the safety of long-term opioid therapy for chronic pain management are few. For example, one Australian study found that long-term opioid use was associated with risky behavior like seeking an early prescription refill. However, it does not focus on more pressing issues like an opioid overdose. What is worrisome is that we may never see any large clinical trials regarding opioid use in chronic pain happening. Nevertheless, there is a major shift in attitude toward opioids, and public health policies are changing fast and discouraging opioid use. In fact, during the course of chronic pain management and treatment, the excessive use of opioids can lead to long term addiction. one might then have to look for a dedicated opioid addiction treatment.
Of course, many studies are being published regularly regarding opioid use. But those are reviews, meta-analyses, and retrospective studies based on old clinical findings and data. Hence, any new study based on old and poor-quality data cannot answer relevant questions confidently.