Pharmacologic treatment for low back pain: one component of pain care

Nonsurgical treatments for patients with radicular pain from lumbosacral disc herniation

BACKGROUND CONTEXT

Lumbosacral disc herniation (LDH) is one of the most frequent musculoskeletal diseases causative of sick leave in the workplace and morbidity in daily activities. Nonsurgical managements are considered as first line treatment before surgical treatment.

PURPOSE

This clinical practice guideline (CPG) is intended to provide physicians who treat patients diagnosed with LDH with a guideline supported by scientific evidence to assist in decision-making for appropriate and reasonable treatments.

STUDY DESIGN/SETTING

A systematic review.

PATIENT SAMPLE

Studies of human subjects written in Korean or English that met the following criteria were selected: patients aged ≥18 years, clinical presentation of low back and radicular leg pain, diagnosis of LDH on radiological evaluation including computed tomography or magnetic resonance imaging.

OUTCOMES MEASURES

Pain and functional evaluation scales such as visual analogue scale, numeric rating scale, and Oswestry disability index METHODS: The MEDLINE (PubMed), EMBASE, Cochrane Review, and KoreaMed databases were searched for articles regarding non-surgical treatments for LDH published up to July 2017. Of the studies fulfilling these criteria, those investigating clinical results after non-surgical treatment including physical and behavioral therapy, medication, and interventional treatment in terms of pain control and functional improvements were chosen for this study.

RESULTS

Nonsurgical treatments were determined to be clinically effective with regards to pain reduction and functional improvement in patients with LDH. Nevertheless, the evidence level was generally not evaluated as high degree, which might be attributed to the paucity of well-designed randomized controlled trials. Exercise and traction were strongly recommended despite moderate level of evidence. Epidural injection was strongly recommended with high degree of evidence and transforaminal approach was more strongly recommended than caudal approach.

CONCLUSIONS

This CPG provides new and updated evidence-based recommendations for treatment of the patients with LDH, which suggested that, despite an absence of high degrees of evidence level, non-surgical treatments were clinically effective.

The effect of journal impact factor, reporting conflicts, and reporting funding sources, on standardized effect sizes in back pain trials: a systematic review and meta-regression

BACKGROUND

Low back pain is a common and costly health complaint for which there are several moderately effective treatments. In some fields there is evidence that funder and financial conflicts are associated with trial outcomes. It is not clear whether effect sizes in back pain trials relate to journal impact factor, reporting conflicts of interest, or reporting funding.

METHODS

We performed a systematic review of English-language papers reporting randomised controlled trials of treatments for non-specific low back pain, published between 2006-2012. We modelled the relationship using 5-year journal impact factor, and categories of reported of conflicts of interest, and categories of reported funding (reported none and reported some, compared to not reporting these) using meta-regression, adjusting for sample size, and publication year. We also considered whether impact factor could be predicted by the direction of outcome, or trial sample size.

RESULTS

We could abstract data to calculate effect size in 99 of 146 trials that met our inclusion criteria. Effect size is not associated with impact factor, reporting of funding source, or reporting of conflicts of interest. However, explicitly reporting 'no trial funding' is strongly associated with larger absolute values of effect size (adjusted β=1.02 (95 % CI 0.44 to 1.59), P=0.001). Impact factor increases by 0.008 (0.004 to 0.012) per unit increase in trial sample size (P<0.001), but does not differ by reported direction of the LBP trial outcome (P=0.270).

CONCLUSIONS

The absence of associations between effect size and impact factor, reporting sources of funding, and conflicts of interest reflects positively on research and publisher conduct in the field. Strong evidence of a large association between absolute magnitude of effect size and explicit reporting of 'no funding' suggests authors of unfunded trials are likely to report larger effect sizes, notwithstanding direction. This could relate in part to quality, resources, and/or how pragmatic a trial is.

Structural integration as an adjunct to outpatient rehabilitation for chronic nonspecific low back pain: a randomized pilot clinical trial

Structural Integration (SI) is an alternative method of manipulation and movement education. To obtain preliminary data on feasibility, effectiveness, and adverse events (AE), 46 outpatients from Boston area with chronic nonspecific low back pain (CNSLBP) were randomized to parallel treatment groups of SI plus outpatient rehabilitation (OR) versus OR alone. Feasibility data were acceptable except for low compliance with OR and lengthy recruitment time. Intent-to-treat data on effectiveness were analyzed by Wilcoxon rank sum, n = 23 per group. Median reductions in VAS Pain, the primary outcome, of -26 mm in SI + OR versus 0 in OR alone were not significantly different (P = 0.075). Median reductions in RMDQ, the secondary outcome, of -2 points in SI + OR versus 0 in OR alone were significantly different (P = 0.007). Neither the proportions of participants with nor the seriousness of AE were significantly different. SI as an adjunct to OR for CNSLBP is not likely to provide additional reductions in pain but is likely to augment short term improvements in disability with a low additional burden of AE. A more definitive trial is feasible, but OR compliance and recruitment might be challenging. This trial is registered with ClinicalTrials.gov (NCT01322399).

Real-world treatment patterns and opioid use in chronic low back pain patients initiating duloxetine versus standard of care

To describe the use of pain medications in patients with chronic low back pain (CLBP) after initiating duloxetine or standard of care (SOC [muscle relaxants, gabapentin, pregabalin, venlafaxine, and tricyclic antidepressants]) for pain management, pharmacy and medical claims from Surveillance Data, Inc (SDI) Health were analyzed. Adult patients with CLBP who initiated duloxetine or SOC between November 2010 and April 2011 were identified. Treatment initiation was defined as no pill coverage for duloxetine or SOC in the previous 90 days. Included patients had no opioid use in the 90 days before initiation. Propensity score matching was used to select patients with similar baseline demographic and clinical characteristics for duloxetine and SOC cohorts. Compliance with index medication was assessed via medication possession ratio (MPR) and proportion of days covered (PDC) for 6 months after initiation. The proportion of patients receiving opioids and days on opioids after index date were assessed, and regression models were estimated to compare opioid use between cohorts. A total of 766 patients initiated duloxetine and 6,206 patients initiated SOC. After matching, 743 patients were selected for the duloxetine (mean age 57 years; female 74%) and SOC (mean age 57 years; female 75%) cohorts, respectively. Of the duloxetine cohort, 92% started on or below recommended daily dose (≤60 mg). The duloxetine cohort had significantly higher MPR (0.78 versus [vs] 0.60) and PDC (0.50 vs 0.31), were less likely to use opioids (45% vs 61%), and had fewer days on opioids (median 0 vs 7 days) than the SOC cohort (all P < 0.001). After adjusting for demographic and clinical characteristics, the duloxetine cohort initiated opioids later than the SOC cohort (hazard ratio 0.77, 95% confidence interval 0.66–0.89). CLBP patients initiating duloxetine had better compliance with initiated medication and were less likely to use opioids than those initiating SOC.

Low back pain: pharmacologic management

Adequate treatment of low back pain is essential, but has been challenging for many primary care physicians. Most patients with low back pain can be treated in the primary care environment, provided the physician has enough knowledge of the medications used to treat low back pain. The main treatment goal for acute low back pain is to control the pain and maintain function. For patients with chronic back pain, the goal is continual pain management and prevention of future exacerbations. This article reviews current pharmacological options for the treatment of low back pain, and possible future innovations.