Does pain duration and other variables measured at baseline predict re-referral of low back pain patients managed on an evidence-based pathway? A cohort study.

OBJECTIVE: To explore the association between baseline pain duration and the likelihood of re-referral of patients with low back pain (LBP) managed on the evidence-based North East of England Regional Back Pain and Radicular Pain Pathway (NERBPP). STUDY DESIGN: Longitudinal, observational cohort study. METHODS: In all, 12,509 adults with LBP were identified as having been discharged from the pathway, between May 2015 and December 2019. To quantify any association between baseline pain duration and the likelihood of re-referral, two statistical modelling approaches, were used: logistic regression models for odds ratios and generalised linear models with a binomial link function in order to quantify risk differences. RESULTS: Twenty-five percent of patients with LBP, who were discharged, re-referred for management over a 4.5-year period. A large difference in pain duration of 2 SD days was statistically associated with re-referral, with an odds ratio of 1.22 (95% CI: 1.03, 1.44) and a risk difference of 3.6% (95% CI: 0.6, 6.6). Nevertheless, the predictive value of an individual's pain duration was found to be weak for re-referral. Higher baseline disability [odds ratio of 1.40 (95% CI: 1.07, 1.83)] and a younger age at baseline [odds ratio of 0.73 (95% CI 0.61, 0.86)] were also associated with an increased risk of re-referral. CONCLUSIONS: Baseline pain duration, disability and younger age are statistically associated with re-referral onto the NERBPP. However, the value of these variables for predicting an individual's risk of re-referral is weak. CONTRIBUTION OF PAPER.

Long-term improvements following a residential combined physical and psychological programme for chronic low back pain.

OBJECTIVES: Evaluate the outcomes and explore experiences of patients undergoing a residential combined physical and psychological programme (CPPP) for chronic low back pain. DESIGN: A longitudinal observational cohort design, with a parallel qualitative design using semistructured interviews. SETTING: Residential, multimodal rehabilitation. PARTICIPANTS: 136 adults (62 male/74 female) referred to the CPPP, 100 (44 male/56 female) of whom completed the programme, during the term of the study. Ten (2 male/8 female) participated in the qualitative evaluation. INTERVENTION: A 3-week residential CPPP. OUTCOME MEASURES: Primary outcome measures were the STarT Back screening tool score; pain intensity-11-point Numerical Rating Scale; function-Oswestry Disability Index (ODI); health status/quality of life-EQ-5D-5L EuroQol five-Dimension-five level; anxiety-Generalised Anxiety Disorder-7; depression-Patient Health Questionnaire-9. Secondary outcome measures were the Global Subjective Outcome Scale; National Health Service Friends and Family Test;. RESULTS: At discharge, 6 and 12 months follow ups, there were improvements from baseline that were greater than minimum clinically important differences in each of the outcomes (with the sole exception of ODI at discharge). At 12 months, the majority of people considered themselves a lot better (57%) and were extremely likely (86%) to recommend the programme to a friend. The qualitative data showed praise for the residential nature of the intervention and the opportunities for interaction with peers and peer support. There were testimonies of improvements in understanding of pain and how to manage it better. Some participants said they had reduced, or stopped, medication they had been taking to manage their pain. CONCLUSIONS: Participants improved, and maintained long term, beyond minimum clinically important differences on a wide range of outcomes. Participants reported an enhanced ability to self-manage their back pain and support for the residential setting.

Exploring the origin of pain subclassification, with emphasis on low back pain: a scoping review.

OBJECTIVE: This scoping review aimed to explore the different working definitions for the duration of acute, subacute, and chronic pain, with emphasis on low back pain, and to establish where these definitions originated and the rationale provided for the time frames used. INTRODUCTION: From a global perspective, low back pain is a major social and economic problem. One of the most commonly used methods to stratify and manage low back pain is the traditional duration-based classification (acute, subacute, and chronic). Where these time points lie to differentiate these transitions continues to be debated within the scientific community, which may engender a degree of heterogeneity in study findings. Therefore, applying these findings to clinical practice may be somewhat challenging. This review encapsulates the historical origins of the different duration categories to provide an understanding of how these variations were derived. INCLUSION CRITERIA: Studies that included participants with low back pain were the focus of this review. Sources that included children or other specific pain pathologies, such as cancer pain, were excluded. The main concept of interest was that the publication proposed an original definition of the duration of acute, subacute, or chronic low back pain. All study designs were included provided they gave a rationale for the duration that they used. METHODS: The following databases were searched: MEDLINE, Embase, CINAHL, and PsycINFO, from the inception of each database until September 18, 2019. This review was limited to studies published in English. Two independent reviewers screened the retrieved articles against the eligibility criteria. Additional studies were searched from the reference lists of studies to find the original source. Some original sources overlapped with general pain duration literature. This led to a deviation from the scoping review protocol, which originally intended to focus on definitions of low back pain duration only. Data extraction was undertaken using a charting table developed specifically for the review objectives. The findings were presented using narrative synthesis. RESULTS: Nineteen records were included in this review, and comprised three book chapters, four review articles, four articles that arose following pain expert group discussions, seven primary research studies, and a spinal guideline. Data were extracted from the included studies and categorized into four themes based on the origin of the classification of the duration. The themes included i) work/employment setting, ii) empirical studies, iii) expert reasoning, and iv) pathophysiological explanation. CONCLUSIONS: This scoping review compiled the existing literature on the working definitions of the duration of acute, subacute, and chronic low back pain and found a wide variation. These ranged from seven days, 14 days, and seven weeks for the acute and subacute transition points, and seven weeks to three years for chronic low back pain. The duration definitions specifically referring to the general pain literature focused on three and/or six months for the transition to chronic. Better integration of reasoning between the identified themes could facilitate the establishment of more ideal duration definitions in the future. Although inconclusive, the definition most commonly cited, with most consensus, was three months for the transition to chronic low back pain.

Does Duration of Pain at Baseline Influence Longer-term Clinical Outcomes of Low Back Pain Patients Managed on an Evidence-Based Pathway?

STUDY DESIGN: Nonrandomized longitudinal observational study. OBJECTIVE: The aim of this study was to evaluate the association between baseline pain duration and medium-to-long term clinical outcomes, in low back pain (LBP) patients enrolled on the North East of England Regional Back Pain and Radicular Pain Pathway (NERBPP). SUMMARY OF BACKGROUND DATA: The NERBPP is based upon National Institute for Health and Care Excellence (NICE) guidelines. These guidelines no longer differentiate management of LBP patients based on pain duration. Medium-to-long term data from the NERBPP is lacking. METHODS: Between May 2015 and December 2019, 786 and 552 LBP patients from the NERBPP returned 6-month and 12-month follow-up outcome measures, respectively. Outcomes included pain (Numerical rating scale), function (Oswestry Disability Index) and quality-of-life (EuroQol five-dimension, five-level questionnaire), analyzed using a series of covariate-adjusted models. Patients were categorized into four groups based upon baseline pain duration: <3 months, ≥3 to <6 months, ≥6 months to <12 months, ≥12 months. RESULTS: Patients with <3 months duration demonstrated clinically important improvements on all outcomes, at both follow-ups. The improvements in outcomes from this group were larger than those in the ≥12 month's duration group (P < 0.05), these group differences in change, in some cases surpassed our threshold for clinical relevance. Functional improvements in those with ≥12 month's duration were not clinically relevant at either follow-up. All patients, regardless of baseline pain duration, reported similar levels of readiness to self-manage at the 12-month follow-up. CONCLUSION: Baseline pain duration would appear to be of clinical importance. Patients with shorter baseline pain duration demonstrated better outcomes. Those with ≥12 month's duration of pain may need additional support during their management to achieve clinically relevant functional improvements in the medium-to-long term. These findings raise questions about the decision by NICE to move away from duration of pain to differentiate management of LBP patients.Level of Evidence: 3.

Exploring the origin of low back pain sub-classification: a scoping review protocol.

OBJECTIVE: This scoping review aims to map the different working definitions currently being used for the duration of acute, subacute and chronic low back pain (LBP), and to establish where these definitions originated and the rationale provided for the timeframes used. INTRODUCTION: Low back pain is a major social and economic problem worldwide. One of the most commonly used approaches to classify and manage patients with LBP is the traditional duration-based classification (acute, subacute and chronic). There are significant differences between studies in the timeframes used for what constitutes acute, subacute and chronic LBP. These discrepancies lead to heterogeneity in study results, making it difficult to compare or summarize findings. INCLUSION CRITERIA: Studies that include participants with non-specific LBP, regardless of sex, will be considered. Studies that include children or participants with specific causes of LBP will be excluded. METHODS: The following electronic databases will be searched: MEDLINE, Embase, CINAHL and PsycINFO. All types of studies will be included, provided they give a rationale for the definition of duration that they use. Studies will be limited to those published in English. Two independent reviewers will screen the retrieved articles against the eligibility criteria for the scoping review. A narrative synthesis will describe the definitions used in the study and the rationale given for the timeframes reported. This scoping review will give an insight into the background of the variation of timeframes used for duration-based classification of LBP.

Does Duration of Pain at Baseline Influence Clinical Outcomes of Low Back Pain Patients Managed on an Evidence-based Pathway?

STUDY DESIGN: Longitudinal observational study. OBJECTIVE: To investigate the association between the duration of pain at baseline and the clinical outcomes of patients with low back pain (LBP) enrolled on the North East of England Regional Back Pain and Radicular Pain Pathway (NERBPP). SUMMARY OF BACKGROUND DATA: The NERBPP is a clinical pathway based upon National Institute for Health and Care Excellence (NICE) guidelines (2009) for LBP of <1-year duration. Recent changes to NICE guidelines (2016) advocate the same management for all LBP patients regardless of pain duration. METHODS: Patients with LBP referred onto the NERBPP by their General Practitioner between May 2015 and January 2017 were included. Data from 667 patients, who provided pre- and post data for pain (Numerical rating scale), function (Oswestry Disability Index), quality-of-life (EuroQol five-dimension, five-level questionnaire), anxiety (the Generalized Anxiety Disorder Screener), and depression (the Patient Health Questionnaire), were analyzed using a series of covariate-adjusted models. Patients were categorized into four groups based upon baseline pain duration: <3 months, ≥3 to <6 months, ≥6 months to <12 months, ≥12 months. RESULTS: Each group showed improved outcomes greater than the minimal clinically important difference (MCID) for each measure as defined in NICE guidelines (2016). There was a trend toward better outcomes for those with shorter pain durations. The magnitude of the differences between the groups, in most instances, was below the MCID. For example, mean improvement in function for those with baseline pain duration <3 months was 20 points and 12 points for those of pain duration ≥12 months, both above the MCID of ≥10. CONCLUSION: Patients with different durations of LBP at baseline improved on the NERBPP, supporting the recent modification to NICE guidelines. However, those with shorter durations of pain may have superior outcomes in the short term, suggesting added benefit in getting patients onto the pathway in the early stages of LBP. LEVEL OF EVIDENCE: 3.