Do strong opioids have a role in the early management of back pain? Recommendations from a European expert panel

Pharmacokinetic and pharmacodynamic evaluation of oxycodone and naltrexone for the treatment of chronic lower back pain

INTRODUCTION

Chronic low back pain (CLBP) is a common and difficult illness to manage. Some individuals with CLBP have pain processing disorders and are also at risk for opioid abuse, misuse; addiction and diversion. Guidelines have been published to guide management; neuromodulation, exercise, mindfulness-based stress reduction and cognitive behavior therapies among other non-pharmacological reduce the pain of CLBP with minimal toxicity. Pharmacological management includes acetaminophen, NSAIDs and antidepressants, mainly duloxetine. Abuse-deterrent opioids have been developed which have been shown to reduce pain and opioid abuse risk. ALO-02 is a tamper-resistant sustained release opioid consisting of extended release oxycodone and sequestered naltrexone. Pivotal studies of ALO-02 have centered on patients with CLBP.

AREAS COVERED

This manuscript will review CLBP, the pivotal analgesic and clinical abuse potential studies of ALO-02. The opinion will cover whether opioids should be used for CLBP, when they should be used and opioid choices.

EXPERT OPINION

ALO-02 is one of several opioids which can be considered in the management of CLBP. The outcome to a trial of opioids should be function rather than analgesia. Most analgesic trials for CLBP have had analgesia as the primary outcome and function has not been vigorously studied as an outcome. Opioids should be considered as a trial only when other non-opioid analgesics have failed to improve analgesia and function. Universal precautions should be routinely part of phase III analgesic trial particularly for chronic non-malignant pain.

Intravenous nonopioid analgesic drugs in chronic low back pain patients on chronic opioid treatment: a crossover, randomised, double-blinded, placebo-controlled study

BACKGROUND

Addition of nonopioid analgesic drugs reduces pain and opioid requirements in acute low back pain. In noncancer chronic low back pain (CLBP), the efficacy of a combined regimen to reduce breakthrough pain has not been proven so far.

OBJECTIVE

Evaluation of the effects of intravenous (i.v.) nonopioid analgesic drugs on pain intensity and lumbar mobility in CLBP patients on chronic opioid therapy.

DESIGN

Randomised, placebo-controlled, double blinded, crossover study.

SETTING

Vienna General Hospital, Austria, from December 2002 to May 2004.

PATIENTS

Thirty-six adults with CLBP on chronic opioid therapy. Inclusion criteria are as follows: American Society of Anesthesiologists' physical status less than 3, visual analogue scale (VAS) more than 4 and no known allergy to any of the used drugs.

INTERVENTION

After written informed consent and VAS assessment, any oral nonopioid analgesic drug (NSAIDs, metamizol, paracetamol) was replaced by placebo 10 days before the first test infusion as a washout period. Coanalgesics (anticonvulsants, antidepressants) were maintained. Each patient received randomly four i.v. test infusions of diclofenac 75 mg (and orphenadrine 30 mg), parecoxib 40 mg, paracetamol 1 g and isotonic saline. A washout time of 72 h was allowed between each infusion.

MAIN OUTCOME MEASURES

Primary outcome was as follows: VAS pain intensity (0 to 100 mm) at inclusion, before and within 30 min after infusion. Secondary outcomes were as follows: Roland-Morris questionnaire, McGill pain questionnaire and a test panel of physical functioning for spinal mobility, muscular endurance, balance and coordination. The differences in means of the above assessments among the groups were analysed.

RESULTS

We found an improvement in VAS from the day of inclusion to the day of each appointment. We observed no improvement in pain intensity (VAS) or in any of the physical functioning tests immediately before versus after administration of the four i.v. drugs. Reductions in sensory, affective and cognitive dimensions of the McGill pain questionnaire were statistically significant in the diclofenac group. A trend of McGill pain questionnaire improvement existed in the other groups.

CONCLUSION

The present data show that the anticipation of an i.v. infusion of nonopioid analgesic drug improves VAS significantly, probably through expectation-related mechanisms. However, single dose i.v. infusions of nonopioid analgesic drugs fail to improve pain intensity and spinal mobility in CLBP patients on chronic opioid treatment, even immediately after the infusion.

A study of National Health Service management of chronic osteoarthritis and low back pain

Aim

To describe treatment and referral patterns and National Health Service resource use in patients with chronic pain associated with low back pain or osteoarthritis, from a Primary Care perspective.

Background

Osteoarthritis and low back pain are the two commonest debilitating causes of chronic pain, with high health and social costs, and particularly important in primary care. Understanding current practice and resource use in their management will inform health service and educational requirements and the design and optimisation of future care.

Method

Multi-centre, retrospective, descriptive study of adults (⩾18 years) with chronic pain arising from low back pain or osteoarthritis, identified through primary care records. Five general practices in Scotland, England (two), Northern Ireland and Wales. All patients with a diagnosis of low back pain or osteoarthritis made on or before 01/09/2006 who had received three or more prescriptions for pain medication were identified and a sub-sample randomly selected then consented to an in-depth review of their medical records (n=264). Data on management of chronic pain were collected retrospectively from patients’ records for three years from diagnosis (‘newly diagnosed’ patients) or for the most recent three years (‘established’ patients).

Findings

Patients received a wide variety of pain medications with no overall common prescribing pattern. GP visits represented the majority of the resource use and ‘newly diagnosed’ patients were significantly more likely to visit their GP for pain management than ‘established’ patients. Although ‘newly diagnosed’ patients had more referrals outside the GP practice, the number of visits to secondary care for pain management was similar for both groups.

Conclusion

This retrospective study confirmed the complexity of managing these causes of chronic pain and the associated high resource use. It provides an in-depth picture of prescribing and referral patterns and of resource use.

Costs associated with treatment of chronic low back pain: an analysis of the UK General Practice Research Database

STUDY DESIGN

Retrospective cohort study of health care costs associated with the treatment of chronic low back pain (CLBP) in the United Kingdom.

OBJECTIVE

To assess 12-month health care costs associated with the treatment of CLBP, using the UK General Practice Research Database.

SUMMARY OF BACKGROUND DATA

CLBP is a common health problem.

METHODS

Data were obtained from the General Practice Research Database, a computerized database of UK primary care patient data. Patients with CLBP were identified for the study period (January 1, 2007, to December 31, 2009) using diagnostic records and pain relief prescriptions (n = 64,167), and 1:1 matched to patients without CLBP (n = 52,986) on the basis of age, sex, and general practitioner's practice. Index date was defined as the first date of CLBP record; the same index date was assigned to matched controls. Multivariate analyses were performed to compare resource use costs (2009 values) in the 12 months after the index date between patients with and without CLBP. A sensitivity analysis was carried out with a more stringent definition for the control group by excluding a broad range of pain conditions.

RESULTS

Total health care costs for patients with CLBP were double those of the matched controls (£1074 vs. £516; P < 0.05). Of the cost difference, 58.8% was accounted for by general practitioner's consultations, 22.3% by referrals to secondary care, and the rest by pain relief medications. The sensitivity analysis revealed an even greater cost difference between the 2 groups (£1052 vs. £304; P < 0.05). Because of the use of a retrospective administrative claims database, this study is subject to selection bias between study cohorts, misidentification of comorbidities, and an inability to confirm adherence to therapy or assess indirect costs and costs of over-the-counter medications.

CONCLUSION

Our findings confirm the substantial economic burden of CLBP, even with direct costs only.

Efficacy and safety of the seven-day buprenorphine transdermal system in opioid-naïve patients with moderate to severe chronic low back pain: an enriched, randomized, double-blind, placebo-controlled study

CONTEXT

This article presents the results of a pivotal Phase 3 study that assesses a new treatment for the management of chronic low back pain: a transdermal patch containing the opioid buprenorphine. In this randomized, placebo-controlled study with an enriched enrollment design, the buprenorphine transdermal system (BTDS) was found to be efficacious and generally well tolerated.

OBJECTIVES

This enriched, multicenter, randomized, double-blind study evaluated the efficacy, tolerability, and safety of BTDS in opioid-naïve patients who had moderate to severe chronic low back pain.

METHODS

Patients who tolerated and responded to BTDS (10 or 20 mcg/hour) during an open-label run-in period were randomized to continue BTDS 10 or 20 mcg/hour or receive matching placebo. The primary outcome was "average pain over the last 24 hours" at the end of the 12-week double-blind phase, collected on an 11-point scale (0=no pain, 10=pain as bad as you can imagine). Sleep disturbance (Medical Outcomes Study subscale) and total number of supplemental analgesic tablets used were secondary efficacy variables.

RESULTS

Fifty-three percent of patients receiving open-label BTDS (541 of 1024) were randomized to receive BTDS (n=257) or placebo (n=284). Patients receiving BTDS reported statistically significantly lower pain scores at Week 12 compared with placebo (least square mean treatment difference: -0.58, P=0.010). Sensitivity analyses of the primary efficacy variable and results of the analysis of secondary efficacy variables supported the efficacy of BTDS relative to placebo. During the double-blind phase, the incidence of treatment-emergent adverse events was 55% for the BTDS treatment group and 52% for the placebo treatment group. Laboratory, vital sign, and electrocardiogram evaluations did not reveal unanticipated safety findings.

CONCLUSION

BTDS was efficacious in the treatment of opioid-naïve patients with moderate to severe chronic low back pain. Most treatment-emergent adverse events observed were consistent with those associated with the use of opioid agonists and transdermal patches.

Opioids for back pain patients: primary care prescribing patterns and use of services

BACKGROUND

Opioid prescribing for noncancer pain has increased dramatically. We examined whether the prevalence of unhealthy lifestyles, psychologic distress, health care utilization, and co-prescribing of sedative-hypnotics increased with increasing duration of prescription opioid use.

METHODS

We analyzed electronic data for 6 months before and after an index visit for back pain in a managed care plan. Use of opioids was characterized as "none," "acute" (≤90 days), "episodic," or "long term." Associations with lifestyle factors, psychologic distress, and utilization were adjusted for demographics and comorbidity.

RESULTS

There were 26,014 eligible patients. Of these, 61% received a course of opioids, and 19% were long-term users. Psychologic distress, unhealthy lifestyles, and utilization were associated incrementally with duration of opioid prescription, not just with chronic use. Among long-term opioid users, 59% received only short-acting drugs; 39% received both long- and short-acting drugs; and 44% received a sedative-hypnotic. Of those with any opioid use, 36% had an emergency visit.

CONCLUSIONS

Prescription of opioids was common among patients with back pain. The prevalence of psychologic distress, unhealthy lifestyles, and health care utilization increased incrementally with duration of use. Coprescribing sedative-hypnotics was common. These data may help in predicting long-term opioid use and improving the safety of opioid prescribing.

Adherence to clinical guidelines for opioid therapy for chronic pain in patients with substance use disorder

BACKGROUND

Patients with chronic non-cancer pain (CNCP) have high rates of substance use disorders (SUD). SUD complicates pain treatment and may lead to worse outcomes. However, little information is available describing adherence to opioid treatment guidelines for CNCP generally, or guideline adherence for patients with comorbid SUD.

OBJECTIVE

Examine adherence to clinical guidelines for opioid therapy over 12 months, comparing patients with SUD diagnoses made during the prior year to patients without SUD.

DESIGN

Cohort study.

PARTICIPANTS

Administrative data were collected from veterans with CNCP receiving treatment within a Veterans Affairs regional healthcare network who were prescribed chronic opioid therapy in 2008 (n = 5814).

KEY RESULTS

Twenty percent of CNCP patients prescribed chronic opioid therapy had a prior-year diagnosis of SUD. Patients with SUD were more likely to have pain diagnoses and psychiatric comorbidities. In adjusted analyses, patients with SUD were more likely than those without SUD to have had a mental health appointment (29.7% versus 17.2%, OR = 1.49, 95% CI = 1.26-1.77) and a urine drug screen (UDS) (47.0% versus 18.2%, OR = 3.53, 95% CI = 3.06-4.06) over 12 months. There were no significant differences between groups on receiving more intensive treatment in primary care (63.4% versus 61.0%), long-acting opioids (26.9% versus 26.0%), prescriptions for antidepressants (88.2% versus 85.8%, among patients with depression), or participating in physical therapy (30.6% versus 28.6%). Only 35% of patients with SUD received substance abuse treatment.

CONCLUSIONS

CNCP patients with SUD were more likely to have mental health appointments and receive UDS monitoring, but not more likely to participate in other aspects of pain care compared to those without SUD. Given data suggesting patients with comorbid SUD may need more intensive treatment to achieve improvements in pain-related function, SUD patients may be at high risk for poor outcomes.

[Opioids for chronic noncancer pain: recommendations based on clinical practice guidelines]

OBJECTIVE

The need for major opioids in the treatment of chronic pain unrelated to cancer is increasing. We therefore appraised available clinical practice guidelines in order to identify recommendations for good practice in the use of these drugs.

MATERIAL AND METHODS

By searching the main guideline repositories as well as resources provided by medical associations, we identified clinical practice guidelines on the use of major opioids published up to 2007. Fourteen of the 28 guidelines we found met the inclusion criteria. To appraise the guidelines we applied the criteria for scientific evidence of the AGREE collaboration (Appraisal of Guidelines Research and Evaluation). The AGREE instrument consists of 23 items organized in 6 areas for appraisal.

RESULTS

Of the 14 guidelines appraised, 5 were judged to be of high quality. In each of the 5 selected guidelines, the relation between a recommendation and the evidence it was based on was stated explicitly; all 5 had overall quality scores over 60%. The recommendations drawn from these guidelines deal with 3 sequential moments in the use of opioids: start of treatment, maintenance therapy, and withdrawal of the drug.

CONCLUSION

The use of opioids to treat chronic noncancer pain is controversial in terms of effectiveness, safety, and the possibility of addiction or abuse. The opioid should be indicated for the pain and prescribed with caution; each case should be assessed individually. Following the recommendations drawn from these guidelines will be important for achieving control of both pain and the accompanying symptoms. The use of major opioids to relieve chronic pain unrelated to cancer, and therefore to improve the quality of life of patients who experience this type of pain, is a legitimate treatment approach.

[Physicians' knowledge and attitudes concerning the use of opioids in the treatment of chronic cancer and non-cancer pain]

INTRODUCTION

The efficacy of opioids has been proved and several guidelines and expert panel-based recommendations regarding the use of opioids in different pain syndromes are available. Nevertheless, undertreatment of pain with strong opioids was reported in previous studies. It was shown that physicians' lack of knowledge, their concerns and misconceptions about the opioid use and the controlled substances regulations that govern the prescriptions of opioids occasionally contribute to insufficient pain treatment. This study was designed to evaluate German physicians' knowledge and their concerns about the use of opioids.

METHOD

During a postgraduate course a questionnaire was completed by German physicians specializing in pain therapy.

RESULTS

A total of 226 physicians completed the questionnaire (response rate 57%). Many of them had poor knowledge of the WHO recommendations for the treatment of cancer pain including the WHO analgesic ladder. Deficiencies in the knowledge of pharmacological aspects and controlled substances regulations were revealed. Many physicians would prescribe strong opioids for non-opioid-sensitive types of pain. The concerns regarding opioid therapy included adverse effects and addiction. In contrast to earlier findings the German controlled substances regulations no longer seem to be a barrier to the prescription of opioids in the treatment of chronic severe pain since they were changed in 1998. As a result, the lack of knowledge and the physicians' concerns about the use of opioids as shown in this survey may likely lead to an insufficient treatment of patients suffering from severe chronic pain.

CONCLUSION

It is necessary to improve the medical students' education and the physicians' postgraduate training regarding principles of pain management such as the WHO guidelines for the treatment of cancer pain. A better knowledge of important pharmacological aspects of opioids should help to reduce physicians' concerns about the use of strong opioids. Nevertheless, improvement of physicians' skills in pain therapy is only one aim in a multidisciplinary concept in order to improve patients' pain therapy.

The course of opioid prescribing for a new episode of disabling low back pain: opioid features and dose escalation

Despite utilization concerns, little information is available on opioid prescribing for acute, disabling low back pain (LBP) and how opioid features (purity, strength, and length of action) and dose change over time. This information is important in targeting guideline implementation efforts and identifying risks for inappropriate prescribing. Using 2002-2003 United States' workers compensation claims, a cohort of 2868 cases with a new episode of work-related LBP and at least one opioid prescription was followed for 2 years. Opioid prescriptions (timing, dose, and formulation), demographics, and medical data were captured. A longitudinal model of change was used to evaluate factors associated with dosing changes. Opioid prescribing typically began early in the course of care (median=8 days, Inter-Quartile Range (IQR)=3, 43 days) and was often prolonged (median=46 days, IQR=14, 329). At the end of the observation period, 7.1% of non-surgical cases and 30.6% of surgical cases were still receiving opioids. The number of days between the initial LBP report and the first opioid prescription had the greatest association with subsequent dose escalation. Dose escalation was greater with pure formulations, and was not related to clinical severity or surgery. In contrast to previous and current guideline recommendations, opioid prescribing for acute LBP was often prolonged, and longer for surgical cases. These results reinforce recommendations to limit opioid duration, and suggest that consideration of opioid features, purity as an important one, can be part of a strategy to prevent escalating dosages.

Opioid prescriptions in canadian workers' compensation claimants: prescription trends and associations between early prescription and future recovery

STUDY DESIGN

Historical cohort study.

OBJECTIVE

We investigated the prescription of opioids in injured Canadian workers to determine recent trends in use and the association between early prescription and future recovery.

SUMMARY OF BACKGROUND DATA

Opioid analgesia is effective for reducing chronic nonmalignant pain, and opioid prescriptions for musculoskeletal pain seem to have increased over the past years. However, recent evidence indicates early opioid use may be associated with delayed recovery in patients with back pain.

METHODS

Data were extracted from the Alberta Workers' Compensation Board administrative database, and information was obtained on all time loss claims for sprains, strains, fractures, dislocations, amputations, or burns between January 1, 2000 and December 31, 2005. Information on all narcotic prescriptions was obtained along with demographic data and duration of time loss benefits. Injury severity was controlled for via nature of injury coding. Analysis included multivariable logistic and Cox regression.

RESULTS

Data were obtained for 137,175 subjects. The majority were males ( approximately 70%) with back sprains (approximately 35%), and a mean age of 37 years. Between the years 2000 and 2005, all opioid prescriptions within the first year of claim decreased from 11.4% of claimants to 8.3%. Older males with fractures, dislocations, or amputations were more likely to receive narcotics. Claimants receiving early opioid prescriptions experienced delayed suspension of benefits. However, this association was also seen in claimants prescribed early non-narcotic analgesics.

DISCUSSION

Prescriptions for opioid analgesia appear to be decreasing within workers' compensation claimants in Alberta, Canada. As expected, claimants with more severe injuries were more likely to receive opioids. An association was observed between early opioid prescription and delayed recovery, however, this is likely explained by pain severity or other unmeasured confounders.

Current management of pain associated with multiple sclerosis

While pain is a common problem in patients with multiple sclerosis (MS), it is not frequently mentioned by patients and a more direct approach is required in order to obtain information about pain from patients. Many patients with MS experience more than one pain syndrome; combinations of dysaesthesia, headaches and/or back or muscle and joint pain are frequent. For each pain syndrome a clear diagnosis and therapeutic concept needs to be established. Pain in MS can be classified into four diagnostically and therapeutically relevant categories: (i) neuropathic pain due to MS (pain directly related to MS); (ii) pain indirectly related to MS; (iii) MS treatment-related pain; and (iv) pain unrelated to MS. Painful paroxysmal symptoms such as trigeminal neuralgia (TN), or painful tonic spasms are treated with antiepileptics as first choice, e.g. carbamazepine, oxcarbazepine, lamotrigine, gabapentin, pregabalin, etc. Painful 'burning' dysaesthesias, the most frequent chronic pain syndrome, are treated with TCAs such as amitriptyline, or antiepileptics such as gabapentin, pregabalin, lamotrigine, etc. Combinations of drugs with different modes of action can be particularly useful for reducing adverse effects. While escalation therapy may require opioids, there are encouraging results from studies regarding cannabinoids, but their future role in the treatment of MS-related pain has still to be determined. Pain related to spasticity often improves with adequate physiotherapy. Drug treatment includes antispastic agents such as baclofen or tizanidine and in patients with phasic spasticity, gabapentin or levetiracetam are administered. In patients with severe spasticity, botulinum toxin injections or intrathecal baclofen merit consideration. While physiotherapy may ameliorate malposition-induced joint and muscle pain, additional drug treatment with paracetamol (acetaminophen) or NSAIDs may be useful. Moreover, painful pressure lesions should be avoided by using optimally adjusted aids. Treatment-related pain associated with MS can occur with subcutaneous injections of interferon-beta or glatiramer acetate, and may be reduced by optimizing the injection technique and by local cooling. Systemic (particularly 'flu-like') adverse effects of interferons, e.g. myalgias, can be reduced by administering paracetamol, ibuprofen or naproxen. A potential increase in the frequency of pre-existing headaches after starting treatment with interferons may require optimization of headache attack therapy or even prophylactic treatment. Pain unrelated to MS, such as back pain or headache, is common in patients with MS and may deteriorate as a result of the disease. In summary, a careful analysis of each pain syndrome will allow the design of the appropriate treatment plan using various medical and nonmedical options (multimodal therapy), and will thus help to improve the quality of life (QOL) of the patients.

Management of musculoskeletal pain

Chronic musculoskeletal pain is a major public health problem affecting about one third of the adult population. Pain is often present without any specific findings in the musculoskeletal system and a strictly biomedical approach could be inadequate. A biopsychosocial model could give a better understanding of symptoms and new targets for management. Identification of risk factors for chronicity is important for prevention and early intervention. The cornerstones in management of chronic non-specific, and often widespread, musculoskeletal pain are non-pharmacological. Physical exercise and cognitive behavioral therapy, ideally in combination, are first line treatments in e.g. chronic low back pain and fibromyalgia. Analgesics are useful when there is a specific nociceptive component, but are often of limited usefulness in non-specific or chronic widespread pain (including fibromyalgia). Antidepressants and anticonvulsants could be of value in some patients but there is a need for more knowledge in order to give general recommendations.

A 12-week, randomized, placebo-controlled trial assessing the safety and efficacy of oxymorphone extended release for opioid-naive patients with chronic low back pain

OBJECTIVE

Determine the efficacy and tolerability of oxymorphone extended release (OPANA ER) in opioid-naive patients with moderate to severe chronic low back pain (CLBP).

DESIGN AND METHODS

Patients > or = 18 years of age were titrated with oxymorphone ER (5- to 10-mg increments every 12 h, every 3-7 days) to a well-tolerated, stabilized dose. Patients were then randomized to continue their oxymorphone ER dose or receive placebo every 12 h for 12 weeks. Oxymorphone immediate release was available every 4-6 h, as needed, for the first 4 days and twice daily thereafter.

RESULTS

Sixty-three percent of patients (205/325) were titrated to a stabilized dose of oxymorphone ER, most (203/205) within 1 month. During titration, 18% discontinued from adverse events (AEs) and 1% from lack of efficacy. For patients completing titration, average pain intensity decreased from 69.4 mm at screening to 22.7 mm (p < 0.0001). After randomization, 68% of oxymorphone ER and 47% of placebo patients completed 12 weeks of double-blind treatment. Approximately 8% of patients in each group discontinued because of AEs. Placebo patients discontinued significantly sooner from lack of efficacy than those receiving oxymorphone ER (p < 0.0001). Pain intensity increased significantly more in the placebo group (least squares [LS] mean change 26.9 +/- 2.4 [median 28.0]) than in the oxymorphone ER group (LS mean change 10.0 +/- 2.4 [median 2.0]; p < 0.0001). Oxymorphone ER was generally well tolerated without unexpected AEs. Although limitations of a randomized withdrawal study include the potential for unblinding and opioid withdrawal in placebo patients, opioid withdrawal was limited to two patients in the placebo group and one in the oxymorphone ER group.

CONCLUSIONS

Stabilized doses of oxymorphone ER were generally safe and effective over a 12-week double-blind treatment period in opioid-naive patients with CLBP.