HPE Chronic pain – part one - Page 9

management of the patient’s condition. Radiographic studies and laboratory tests should not be routinely ordered for patients with acute symptoms; rather, they should be used selectively based upon the history, physical examination, and the initial response to treatment. Finally, the identification of ‘yellow flags’ and ‘blue flags’ (factors that might contribute to a poor prognosis; see Table 2) becomes relevant in patients who do not make a rapid recovery. These factors need to be identified and rectified early to avoid the risk of developing chronic pain and disability. 6 Because most individuals with low back pain (90%) will have a self-limited, non-specific mechanical cause, the goal of the clinical evaluation is ultimately to efficiently identify rare serious causes as well as those patients who might be at higher risk for delayed improvement due to neurological impairment or psychosocial factors. ‘Chronification’ and treatment In many countries, clinical guidelines have been issued for the management of low back pain and, in general, the recommendations are similar across guidelines worldwide. Currently, the treatment for chronic low back pain is mostly symptomatic. That exercise (such as aquatic exercises, stretching, strength training, and endurance) and intensive multidisciplinary pain treatment programmes with educational interventions and (cognitive) behaviour therapy are effective for chronic low back pain, is supported by strong evidence. Fewer data support the effectiveness of analgesics, antidepressants, NSAIDs or opioids Although evidence of effectiveness and safety associated with long-term treatment is currently limited for all conventional opioids, a new molecule characterised by a unique mechanism of action acting at both, the nociceptive and neuropathic components of pain has come into focus for the treatment of a mixed pain conditions such as back pain. The atypical opioid tapentadol is a dual μ-opioid receptor (MOR) agonist and noradrenaline reuptake inhibitor (NRI), which represents the first and unique member of a new class of analgesic agents, MOR-NRI. 13 Due to the synergistic interaction of the two mechanisms, lower opioid activity is needed to reach comparable analgesia and therefore a more favourable tolerability profile is achieved, in terms of gastrointestinal, respiratory, and endocrinological adverse events. This is of utmost importance, given the frequent need of long-term treatment in patients with low back pain. But whichever opioid is chosen, prescriptions should always be for a limited period with the lowest effective dose that provides meaningful pain relief and improved function with manageable side effects. Risk mitigation and reassessment strategies should be routinely incorporated. It should be borne in mind that opioids are not first-line treatment for low back pain and might not be appropriate in all patients; however, the benefits might outweigh the risks after a thorough evaluation and if other drugs are contraindicated, not tolerated, or ineffective. Although the use of anticonvulsants (for example, gabapentin, pregabalin) has increased substantially in recent years, despite moderate evidence that they are ineffective for treatment of low back and lumbar radicular pain, the latest results suggest that the recommendations from guidelines regarding neuropathic pain should not be extended to sciatica. 14 However, based on the underlying pain type, their use in clinical routine is common, especially if patients suffer from comorbidities such FIGURE 1 The painDETECT screening tool About 90% of all patients will have non-specific low back pain, which, in essence, is a diagnosis based on exclusion of a specific pathology as depression, anxiety or sleep disorders. The same holds true for antidepressants. 1,5,15 When drugs are used for symptomatic treatment, patients should be treated with the most suitable agent, at the lowest possible dose and for the shortest time possible. For patients without significant neurological impairment, the initial treatment should include activity modification, non-narcotic analgesics and education; for those whose symptoms do not improve after 2–4 weeks, referral for physical treatments is mandatory. 5 Invasive procedures in (non-specific) chronic low back pain (that is, facet joint, epidural, trigger point interventions) have shown conflicting results. Spinal cord stimulation (SCS) is gaining increasing indications in an expanding variety of clinical conditions. The most common application in the last decades has been the treatment of persistent pain following low back surgery. There is good evidence for SCS as a treatment for failed back surgery syndrome (FBSS) with persistent axial and radicular complaints, as well as for SCS vs. re-operative surgical management for FBSS. 16 Pain in the low back has proven more difficult to treat than radiating leg pain, and no sound evidence is available for the efficacy of surgery. Surgical discectomy as a last resort may be considered for selected patients with sciatica due to lumbar disc prolapse that do not respond to initial conservative management. Fusion surgery, under debate for decades, has yet to show convincing evidence. Most patients have self-limited episodes of acute low back pain, which might resolve without treatment. However, in some cases people present with recurrent episodes, with longer duration and more debilitating in their nature. In fact, it is rare to have true remission, with a single episode of pain never recurring. This ‘chronification’ of low back pain is problematic because of the long-term side effects, including risk of addiction, of some of the drugs used to alleviate pain. 1 Although physicians typically manage patients based upon the duration of symptoms (acute, subacute, and chronic) and the presence of hospitalpharmacyeurope.com | 2019 | 9