Psychological flexibility in adults with chronic pain: A study of acceptance,mindfulness, and values-based action in primary care

There is an increasing number of studies of acceptance, mindfulness, and values-based action in relation to chronic pain. Evidence from these studies suggests that these processes may be important for reducing the suffering and disability arising in these conditions. Taken together these processes entail an overarching process referred to as “psychological flexibility.” While these processes have been studied in people with chronic pain contacted in specialty treatment centers, they have not yet been investigated in primary care. Thus, participants in this study were 239 adults with chronic pain surveyed in primary care, through contact with their General Practitioners (GPs), in the UK. They completed measures of acceptance of chronic pain, mindfulness, psychological acceptance, values-based action, health status, and GP visits related to pain. Correlation coefficients demonstrated significant relations between the components of psychological flexibility and the measures of health and GP visits. In regression analyses, including both pain intensity and psychological flexibility as potential predictors, psychological flexibility accounted for significant variance, ΔR² = .039–.40 (3.9–40.0%). In these regression equations pain intensity accounted for an average of 9.2% of variance while psychological flexibility accounted for 24.1%. These data suggest that psychological flexibility may reduce the impact of chronic pain in patients with low to moderately complex problems outside of specialty care. Due to a particularly conservative recruitment strategy the overall response rate in this study was low and the generality of these results remains to be established.     

Conceptual overlap of psychological constructs in low back pain

The biopsychosocial model is increasingly accepted in low back pain (LBP) research and clinical practice. In order to assess the role of psychological factors in the development and persistence of pain, a wide array of measures has been developed. Yet there is likely to be considerable conceptual overlap between such measures, and consequently, a lack of clarity about the importance of psychological factors. The aims of this study were to investigate the extent of any such overlap. An observational cohort study of 1591 LBP patients consulting in primary care completed data on a range of psychological instruments. Exploratory and confirmatory factor analyses (EFA and CFA, respectively) were carried out at the subscale level (n = 20) to investigate factor structure. The influences of the derived factors on clinical outcomes (pain intensity and self-reported disability) were then tested using linear regression. EFA yielded 4 factors, termed “Pain-related distress,” “Cognitive coping,” “Causal beliefs,” and “Perceptions of the future,” which accounted for 65.5% of the variance. CFA confirmed the validity of these factors models. The pain-related distress factor was found to have the strongest association to LBP patients’ outcomes, accounting for 34.6% of the variance in pain intensity, and 51.1% of the variance in disability. Results confirmed that considerable overlap exists in psychological measures commonly used in LBP research. Most measures tap into patients’ emotional distress. These findings help us to understand how psychological constructs relate together; implications for future research and clinical practice are discussed.     

The Comparative Prognostic Value of Directional Preference and Centralization: A Useful Tool for Front-Line Clinicians?

Abstract

A large number of prognostic factors have been associated with recovery from an episode of back pain, and much emphasis has been placed on psychosocial prognostic factors. The large number of prognostic factors and the lack of comparative analysis of different factors make use of these difficult in clinical practice. The aim of this study was to evaluate the comparative usefulness of a range of factors to predict outcome using data from a randomized controlled trial (RCT) in which 312 patients with sub-acute to chronic back pain received a mechanical evaluation and were sub-grouped based on the presence or absence of directional preference (DP). Patients were then randomized to treatment that was matched or unmatched to that DP. Patients with a minimal reduction of 30% in Roland-Morris Disability Questionnaire (RMDQ) score were defined as the good outcome group. Seventeen baseline variables were entered into a step-wise logistic regression analysis for the ability to predict a good outcome. Of the patients, 84 met the good outcome criteria and had a mean RMDQ decrease of 58.2% (9.8 points) in 4 visits. Leg pain, work status, depression, pain location, chronicity, and treatment assignment were significant predictors of outcome in univariate analysis. Only leg bothersomeness rating and treatment assignment survived multivariate analysis. Subjects with DP/centralization who received matched treatment had a 7.8 times greater likelihood of a good outcome. Matching patients to their DP is a stronger predictor of outcome than a range of other biopsychosocial factors.     

Associations between weather conditions and clinical symptoms in patients with hip osteoarthritis: A 2-year cohort study

The goal of this study was to assess whether there is an association between ambient weather conditions and patients’ clinical symptoms in patients with hip osteoarthritis (OA). The design was a cohort study with a 2-year follow-up and 3-monthly measurements and prospectively collected data on weather variables. The study population consisted of 222 primary care patients with hip OA. Weather variables included temperature, wind speed, total amount of sun hours, precipitation, barometric pressure, and relative humidity. The primary outcomes were severity of hip pain and hip disability as measured with the Western Ontario and McMasters University Osteoarthritis Index (WOMAC) pain and function subscales. Associations between hip pain and hip disability and the weather variables were assessed using crude and multivariate adjusted linear mixed-model analysis for repeated measurements. On the day of questionnaire completion, mean relative humidity was associated with WOMAC pain (estimate 0.1; 95% confidence interval = 0.0–0.2; P = .02). Relative humidity contributed ?1% to the explained within-patient variance and between-patient variance of the WOMAC pain score. Mean barometric pressure was associated with WOMAC function (estimate 0.1; 95% confidence interval = 0.0–0.1; P = .02). Barometric pressure contributed ?1% to the explained within-patient variance and between-patient variance of the WOMAC function score. The other weather variables were not associated with the WOMAC pain or function score. Our results support the general opinion of OA patients that barometric pressure and relative humidity influence perceived OA symptoms. However, the contribution of these weather variables (?1%) to the severity of OA symptoms is not considered to be clinically relevant.     

Natural course of acute neck and low back pain in the general population: The HUNT study

In this prospective cohort study we aimed to describe the natural course of acute neck and low back pain in a general population of Norway. We screened 9056 subjects aged 20–67 years who participated in a general health survey for a new episode of neck or low back pain the previous month. The screening identified 219 subjects who formed the cohort for this study. Pain intensity was reported on a numeric rating scale (0–10) at 1, 2, 3, 6, and 12 months after start of the new pain episode. The course of pain was described for neck and low back pain, different baseline pain levels, age groups, and number of pain sites at baseline. Use of medication and health care was described and associations between pain intensity and seeking health care were estimated. Pain declined rapidly within 1 month after a new pain episode, with a reduction of 0.91 (95% confidence interval [CI] 0.50–1.32) for neck pain and 1.40 (95% CI 0.82–1.99) for low back pain with little change thereafter. However, pain remained unchanged over the follow-up year for those with equal pain in the neck and low back areas at baseline and for those reporting 4 or more pain sites at baseline. Only 1 in 5 sought health care for their complaints. Still, the course of pain was comparable to effect sizes reported in interventional studies. This study thus contributes natural course reference data for comparisons of pain outcome in clinical trials and practice.     

Shiatsu for chronic lower back pain: Randomized controlled study

BackgroundAlthough Shiatsu, a kind of complementary alternative medicine, was developed in Japan and is practiced around the world, no experimental studies on Shiatsu have been conducted. The aim of this study is to investigate the efficacy of Shiatsu therapy for chronic lower back pain.MethodWe conducted a prospective, randomized, open, blinded-endpoint design study at St. Luke’s International Hospital, Tokyo, Japan from 2015 to 2017. Patients with lower back pain for more than 12 weeks and a score of four or more on the Roland-Morris Disability Questionnaire (RMDQ) at baseline were included in this study. We excluded patients with severe conditions, such as bone metastasis, or dementia. Patients were randomly allocated to either Shiatsu therapy in addition to standard care or standard care only by computer randomization. Those allocated to Shiatsu received one-hour Shiatsu every week for four weeks. Our primary outcome was improvement of RMDQ, and secondary outcomes were improvement of Short-Form McGill Pain Questionnaire (SF-MPQ), Oswestry Disability Index (ODI) and EQ-5D after 4 weeks and 8 weeks. Bivariate analyses were applied for assessing statistical significance.ResultFifty-nine patients were included; 30 were allocated to Shiatsu, and 29 to the control group. None of the baseline characteristics were significantly different between groups. Twenty seven patients (90%) in the Shiatsu group and 24 patients (83%) in the control group completed the study. At week 4, Shiatsu group tended to show greater improvement only in EQ-5D (difference 0.068, p = 0.07), but not statistically significant, compared to control group, wheres other outcome measures were similar between the groups. At week 8, those in the Shiatsu group tended to have greater improvement in RMDQ (difference 1.7, p = 0.08) compared to the control group. The Shiatsu group showed greater improvement in present pain scale of SF-MPQ (difference 0.5, p < 0.05), ODI (difference 4.0, p < 0.01) and EQ-5D (difference 0.099, p = 0.01) compared to control group.ConclusionIn our limited sample trail, Shiatsu therapy combined with standard care for lower back pain improves some symptoms and QOL shortly after Shiatsu therapy.     

Yoga,Eurythmy Therapy and Standard Physiotherapy (YES-Trial) for Patients With Chronic Non-specific Low Back Pain: A Three-Armed Randomized Controlled Trial

We aimed to evaluate the effects of yoga and eurythmy therapy compared to conventional physiotherapy exercises in patients with chronic low back pain. In a three-armed, multicentre, randomized controlled trial, patients with chronic low back pain were treated for 8 weeks in group sessions (75 minutes once per week). Primary outcome was patients’ physical disability (measured by RMDQ) from baseline to week 8. Secondary outcome variables were pain intensity and pain-related bothersomeness (VAS), health-related quality of life (SF-12) and life satisfaction (BMLSS). Outcomes were assessed at baseline, after the intervention at 8 weeks and at a 16-week follow up. Data of 274 participants were used for statistical analyses. There were no significant differences between the three groups for the primary and all secondary outcomes. In all groups, RMDQ decreased comparably at 8 weeks, but did not reach clinical meaningfulness. Pain intensity and pain-related bothersomeness decreased, while quality of life increased in all 3 groups. In explorative general linear models for the SF-12’s mental health component participants in the eurythmy arm benefitted significantly more compared to physiotherapy and yoga. Furthermore, within-group analyses showed improvements of SF-12 mental score for yoga and eurythmy therapy only. All interventions were safe.Clinical Trials Register: DRKS-ID: DRKS00004651Perspective: This article presents the results of a multicentre three-armed randomized controlled trial on the clinical effects of three 8-week programs in patients with chronic low back pain. Compared to the ‘gold standard’ of conventional physiotherapeutic exercises, eurythmy therapy and yoga therapy lead to comparable symptomatic improvements in patients with chronic low back pain. However, the within-group effect sizes were small to moderate and did not reach clinical meaningfulness on patients’ physical disability (RMDQ).     

Illness perceptions of low back pain patients in primary care: what are they, do they change and are they associated with outcome?

We describe the illness perceptions of patients with low back pain, how they change over 6 months, and their associations with clinical outcome. Consecutive patients consulting eight general practices were eligible to take part in a prospective cohort study, providing data within 3 weeks of consultation and 6 months later. Illness perceptions were measured using the Revised Illness Perception Questionnaire (IPQ-R). Clinical outcome was defined using the Roland and Morris Disability Questionnaire (RMDQ) and patients’ global rating of change. Associations between patients, perceptions and poor outcome were analysed using unadjusted and adjusted risk ratios (RR) and 95% confidence intervals. 1591 completed questionnaires were received at baseline and 810 at 6 months. Patients had a mean age of 44 years and 59% were women. Mean (SD) RMDQ score at baseline was 8.6 (6.0) and 6.2 (6.1) at 6 months. 52% and 41% of patients had a poor clinical outcome at 6 months using RMDQ and global rating scores, respectively. There were strong, statistically significant, associations (RRs of 1.4 and over) between IPQ-R baseline consequences, timeline acute/chronic, personal control and treatment control scores and poor outcome. Patients who expected their back problem to last a long time, who perceived serious consequences, and who held weak beliefs in the controllability of their back problem were more likely to have poor clinical outcomes 6 months after they consulted their doctor. These results have implications for the management of patients, and support the need to assess and address patients’ cognitions about their back problems.     

Randomized Controlled Trial of Nurse-Delivered Cognitive-Behavioral Therapy Versus Supportive Psychotherapy Telehealth Interventions for Chronic Back Pain

This study evaluated a nurse-delivered, telehealth intervention of cognitive-behavioral therapy (CBT) versus supportive psychotherapy for chronic back pain. Participants (N?=?61) had chronic back pain (pain “daily”?≥6 months at an intensity of ≥4 of 10 scale) and were randomized to an 8-week, 12-session, CBT or to supportive care (SC) matched for frequency, format, and time, with each treatment delivered by a primary care nurse. The primary outcome was the Roland Morris Disability Questionnaire (RMDQ). Secondary outcomes included the numeric rating scale (NRS) and the Patient Global Impressions Scale (CGI). CBT participants (n?=?30) showed significant improvements on the RMDQ (mean = 11.4 [SD = 5.9] vs 9.4 [SD = 6.1] at baseline and post-treatment, respectively, P?<?.05; d?=?.33), NRS (mean = 4.9 [SD = 2.1] vs 4.0 [SD = 1.9], respectively, P?<?.05; d?=?.45), and on the CGI (39.1% reporting “much improved” or “very much improved”). SC participants (n?=?31) also showed significant improvements on the RMDQ (mean = 11.1 [SD = 5.4] vs 9.1 [SD = 5.2], respectively, P?<?.05; d?=?.38), the NRS, (mean = 5.0 [SD = 1.9] vs 3.8 [SD = 2.1], respectively, P?<?.05; d?=?.60), and 26.7% reporting “much improved” or “very much improved” on the CGI. Between groups comparisons of CBT and SC showed no differences on the study outcomes (Ps > .10). The results suggest that telehealth, nurse-delivered CBT, and SC treatments for chronic back pain can offer significant and relatively comparable benefits.

Compliance effects in a randomised controlled trial of yoga for chronic low back pain: a methodological study

Study design

Methodological study nested within a multicentre randomised controlled trial (RCT) of yoga plus usual general practitioner (GP) care vs usual GP care for chronic low back pain.

Objective

To explore the treatment effects of non-compliance using three approaches in an RCT evaluating yoga for low back pain.

Summary of background data

A large multicentre RCT using intention-to-treat (ITT) analysis found that participants with chronic low back pain who were offered a 12-week progressive programme of yoga plus usual GP care had better back function than those offered usual GP care alone. However, ITT analysis can underestimate the effect of treatment in those who comply with treatment. As such, the data were analysed using other approaches to assess the problem of non-compliance. The main outcome measure was the self-reported Roland Morris Disability Questionnaire (RMDQ).

Methods

Complier average causal effect (CACE) analysis, per-protocol analysis and on-treatment analysis were conducted on the data of participants who were fully compliant, predefined as attendance of at least three of the first six sessions and at least three other sessions. The analysis was repeated for participants who had attended at least one yoga session (i.e. any compliance), which included participants who were fully compliant. Each approach was described, including strengths and weaknesses, and the results of the different approaches were compared with those of the ITT analysis.

Results

For the participants who were fully compliant (n = 93, 60%), a larger beneficial treatment effect was seen using CACE analysis compared with per-protocol, on-treatment and ITT analyses at 3 and 12 months. The difference in mean change in RMDQ score between randomised groups was −3.30 [95% confidence interval (CI) −4.90 to −1.70, P < 0.001] at 3 months and −2.23 (95% CI −3.93 to −0.53, P = 0.010) at 12 months for CACE analysis, −3.12 (95% CI −4.26 to −1.98, P < 0.001) at 3 months and −2.11 (95% CI −3.33 to −0.89, P = 0.001) at 12 months for per-protocol analysis, and −2.91 (95% CI −4.06 to −1.76, P < 0.001) at 3 months and −2.10 (95% CI −3.31 to −0.89, P = 0.001) at 12 months for on-treatment analysis. For the participants who demonstrated any compliance (n = 133, 85%), the results were generally consistent with the fully compliant group at 3 months, but the treatment effect was smaller. The difference in mean change in RMDQ score between randomised groups was −2.45 (95% CI −3.67 to −1.24) for CACE analysis, −2.30 (95% CI −3.43 to 1.17) for per-protocol analysis and −2.15 (95% CI −3.25 to −1.06) for on-treatment analysis, which was slightly less than that for ITT analysis. In contrast, at 12 months, per-protocol and on-treatment analyses showed a larger treatment effect compared with CACE and ITT analyses: per protocol analysis −1.86 (95% CI −3.02 to −0.71), on-treatment analysis −1.99 (95% CI −3.13 to −0.86) and CACE analysis −1.67 (95% CI −2.95 to −0.40).

Conclusion

ITT analysis estimated a slightly smaller treatment effect in participants who complied with treatment. When examining compliance, CACE analysis is more rigorous than per-protocol and on-treatment analyses. Using CACE analysis, the treatment effect was larger in participants who complied with treatment compared with participants who were allocated to treatment, and the difference between ITT and CACE analyses for the fully compliant group at 3 months was small but clinically important. Per-protocol and on-treatment analyses may produce unreliable estimates when the effect of treatment is small.

International Standard Randomised Trial Number Register

ISRCTN 81079604.     

A comparison of pain measures in newborn infants after cardiac surgery

Accurate pain assessment tools to evaluate pain in critically ill neonates in the postoperative period are lacking. Therefore, we compared a number of potentially useful indices of pain in critically ill neonates following cardiac surgery. Eighty-one full-term infants were studied during the first 48 postoperative hours and the following indices were measured: heart rate, mean arterial blood pressure, heart-rate variability, urinary and plasma cortisol, and 4 composite pain measurement scales: Children’s and Infants’ Postoperative Pain Scale (CHIPPS), CRIES, COMFORT, and Premature Infant Pain Profile (PIPP). Regression models were used to investigate relationships between individual pain indices or composite pain assessment scales with respect to procedural intensity and opioid dose and plasma levels. COMFORT score performed best, with a 27% difference in score between procedures causing tissue damage and those that did not (P < 0.001). COMFORT score and the high-frequency component of heart-rate variability showed inverse correlations with opioid dose and plasma levels over the first 48 hours postoperatively, but after accounting for clinical variables, only COMFORT score remained significant (eg, 52% of variance in morphine level at 24 hours, P < 0.001). The factor structure of the COMFORT score revealed that both behavioural and physiological variables account for a significant proportion of the variance (45% and 15%, respectively; P < 0.001). Plasma concentrations of cortisol increased postoperatively but urinary cortisol excretion did not change significantly. Of the pain indices studied, the COMFORT score performed best, with both behavioural and physiological components providing significant contributions.     

Prognostic Indicators of Low Back Pain in Primary Care: Five-Year Prospective Study

Back pain is common and many people experience long-term problems, yet little is known about what prognostic factors predict long-term outcomes. This study's objective was to determine which factors predict short- and long-term outcomes in primary care consulters with low back pain (LBP). Analysis was carried out on 488 patients who had consulted their physician about LBP. Patients were followed up at 6 months and 5 years. Clinically significant LBP at follow-up was defined as a score of 2, 3, or 4 on the Chronic Pain Grade, indicating substantial pain and disability. Cox regression was used to estimate relative risks (RRs) with 95% confidence intervals (CIs) on 32 potential predictive factors, organized into domains (demographic, physical, psychological, and occupational). Baseline pain intensity conferred a 12% increase in risk (RR = 1.12, 95% CI = 1.03–1.20), and patients' belief that their LBP would persist conferred a 4% increase in risk (RR = 1.04, 95% CI = 1.01–1.07) for poor outcome at 6 months. Outcome at 5 years was best predicted by a model with the same factors as in the 6-month model: pain intensity increased risk by 9% (RR = 1.09, 95% CI = .997–1.20), and a belief that their LBP would persist increased risk by 6% (RR = 1.06, 95% CI = 1.03–1.09). Both predictors have the potential to be targets for clinical intervention.PerspectiveFew studies have investigated factors that predict long-term back pain. This study has shown that pain intensity experienced during a period of primary care consultation, and patients' perception about whether their back pain will persist, were significant predictors of poor outcome at 6 months and at 5 years.     

Effect of intravenous tropisetron on modulation of pain and central hypersensitivity in chronic low back pain patients

The activation of 5-hydroxytryptamine-3 (5-HT-3) receptors in spinal cord can enhance intrinsic spinal mechanisms of central hypersensitivity, possibly leading to exaggerated pain responses. Clinical studies suggest that 5-HT-3 receptor antagonists may have an analgesic effect. This randomized, double-blind, placebo-controlled crossover study tested the hypothesis that the 5-HT-3 receptor antagonist tropisetron attenuates pain and central hypersensitivity in patients with chronic low back pain. Thirty patients with chronic low back pain, 15 of whom were women (aged 53 ± 14 years) and 15 men (aged 48 ± 14 years), were studied. A single intravenous injection of 0.9% saline solution, tropisetron 2 mg, and tropisetron 5 mg was administrated in 3 different sessions, in a double-blind crossover manner. The main outcome was the visual analogue scale (VAS) score of spontaneous low back pain before, and 15, 30, 60, and 90 minutes after drug administration. Secondary outcomes were nociceptive withdrawal reflexes to single and repeated electrical stimulation, area of reflex receptive fields, pressure pain detection and tolerance thresholds, conditioned pain modulation, and area of clinical pain. The data were analyzed by analysis of variance and panel multiple regressions. All 3 treatments reduced VAS scores. However, there was no statistically significant difference between tropisetron and placebo in VAS scores. Compared to placebo, tropisetron produced a statistically significant increase in pain threshold after single electrical stimulation, but no difference in all other secondary outcomes was found. A single-dose intravenous administration of tropisetron in patients with chronic low back pain had no significant specific effect on intensity of pain and most parameters of central hypersensitivity.     

Spinal cord stimulation for failed back surgery syndrome: Outcomes in a workers’ compensation setting

Questions remain concerning effectiveness and risks of spinal cord stimulation (SCS) for chronic back and leg pain after spine surgery (“failed back surgery syndrome” [FBSS]). This prospective, population-based controlled cohort study evaluated outcomes of workers’ compensation recipients with FBSS who received at least a trial of SCS (SCS group, n = 51) versus those who (1) were evaluated at a multidisciplinary pain clinic and did not receive SCS (Pain Clinic, n = 39) or (2) received neither SCS nor pain clinic evaluation (Usual Care, n = 68). Patients completed measures of pain, function, medication use, and work status at baseline and 6, 12, and 24 months later. We also examined work time loss compensation over 24 months. Few (<10%) patients in any group achieved success at any follow-up on the composite primary outcome encompassing less than daily opioid use and improvement in leg pain and function. At 6 months, the SCS group showed modestly greater improvement in leg pain and function, but with higher rates of daily opioid use. These differences disappeared by 12 months. Patients who received a permanent spinal cord stimulator did not differ from patients who received some pain clinic treatment on the primary outcome at any follow-up (<10% successful in each group at each follow-up) and 19% had them removed within 18 months. Both trial and permanent SCS were associated with adverse events. In sum, we found no evidence for greater effectiveness of SCS versus alternative treatments in this patient population after 6 months.     

Medical and non-medical direct costs of chronic low back pain in patients consulting primary care physicians in France

A retrospective, observational, cohort study in primary care. To determine the total direct medical and non-medical cost of chronic low back pain (LBP) in France and its associated factors. Chronic LBP affects 5–10% of the population its burden in France is unknown. Ninety-eight randomly selected general practitioners included 796 adult patients with chronic LBP between October 2001 and December 2002. Direct costs due to physician visits, investigations, medications, hospitalizations, and other medical and non-medical resource use were collected for the 6 months prior to study visit. Costs both reimbursed and not by the French health insurance system were considered. Quality of life (QoL) and disease severity were measured using Short Form (SF)-8 and Roland-Morris disability questionnaire (RMDQ), respectively. Costs were updated to represent 2007 prices. Men represented 50.6% of the 796 patients, mean age was 53 ± 11.3 years, and the duration of LBP was more than 1 year in 80.9% of patients. The total mean cost per patient over six months was 715.6€ (95% CI: 644.2–797.8). Of these costs, 22.9% related to care provided by physiotherapists and allied specialists, 19.5% to medications, 17.4% to hospitalizations, 9.6% to investigations, and 12.5% to physician fees. In multivariate analysis, the factors associated with the cost of chronic LBP were disease severity (RMDQ score) and age of the patients. LBP is a disease that is both common and costly.     

Biopsychosocial factors are associated with low back pain in female nursing students: A cross-sectional study

Background

Occupational low back pain is a significant problem among nurses. Recent literature suggests current occupational preventative strategies for nurses have not been effective. Given low back pain is already prevalent before commencing employment, nursing students should be the target of preventative interventions. Modifiable personal factors which contribute to low back pain have proven difficult to identify, but are thought to play an important role in the biopsychosocial nature of low back pain.

Objectives

To evaluate the contribution of personal biopsychosocial factors to low back pain in nursing students.

Design

Cross-sectional study comprising physical testing and questionnaires.

Settings

Two university undergraduate nursing schools in Western Australia.

Participants

170 female undergraduate nursing students.

Methods

Low back pain and control subjects were compared across social, lifestyle (physical activity), psychological (stress, anxiety, depression, back pain beliefs, coping strategies and catastrophising) and physical (spinal postures and spinal kinematics in functional tasks, leg and back muscle endurance, spinal repositioning error and cardiovascular fitness) characteristics. Low back pain was considered as either “minor” or “significant” depending upon pain severity, duration, impact and level of disability.

Results

Over 30% of all subjects (mean age 22.5 ± 4.5 years) reported “significant” low back pain in the preceding 12 months. Univariate analysis: social measures did not distinguish between groups. Subjects with “significant” low back pain were more physically active (p = 0.04), had higher stress scores (p = 0.01) and used passive coping strategies (p < 0.001) more than other subjects. “Significant” low back pain subjects held their lower lumbar spine in a more extended posture during transfers at bed height than other subjects. No differences between groups were found for sagittal spinal mobility, static spinal posture, muscle endurance, spinal repositioning error, cardiovascular fitness or other psychological measures. Multivariate analysis: regression analysis revealed stress, coping, physical activity, spinal kinematics, and age all contributed independently to the presence of low back pain, representing a significant 23% of variance.

Conclusions

Modifiable lifestyle, psychological and physical factors were independently associated with low back pain in nursing students. Targeting personal factors associated with low back pain in nursing students, rather than occupational factors in working nurses may help improve the impact of low back pain in nurses. Prospective studies are required to confirm the relevance of these findings for risk of future low back pain in nurses.     

Pain-related avoidance versus endurance in primary care patients with subacute back pain: psychological characteristics and outcome at a 6-month follow-up

Recent research has found individual differences in back pain patients due to behavioral avoidance vs persistence. However, there is a lack of prospective studies of nonspecific low back pain patients. The avoidance-endurance model (AEM) suggests at least 3 pathways leading to chronic pain: fear-avoidance response, distress-endurance response, and eustress-endurance response. We sought to compare these 3 maladaptive subgroups with an adaptive group using a classification tool that included the following scales: the thought suppression and behavioral endurance subscale of the Avoidance-Endurance Questionnaire and the Beck Depression Inventory. The psychological characteristics, and pain and disability of the AEM subgroups were investigated. We report results from 177 patients with subacute nonspecific low back pain at the start of outpatient treatment and at follow-up after 6 months. At baseline, a multivariate analysis of variance found that the fear-avoidance patients scored higher in pain catastrophizing than the other groups. The distress-endurance patients displayed elevated anxiety/depression and helplessness/hopelessness accompanied with the highest scores in the classification variables thought suppression and persistence behavior. The eustress-endurance patients had the highest humor/distraction scores, pain persistence, and positive mood despite pain. All 3 maladaptive groups revealed a higher pain intensity than the adaptive patients at follow-up after 6 months; however, disability at follow-up was elevated only in the fear-avoidance and distress-endurance patients. The study provides preliminary evidence for the construct and prospective validity of AEM-based subgroups of subacute, nonspecific back pain patients. The results suggest the need for individually targeted cognitive behavioral treatments in the maladaptive groups.     

Avoidance of affective pain stimuli predicts chronicity in patients with acute low back pain

This prospective study of acute and sub-acute low back pain (LBP) patients was conducted to assess whether attentional biases predicted chronic pain status 3 and 6 months later. The attentional biases of 100 LBP patients were assessed within 3 months of developing pain and 6 months later. Participants also completed measures associated with outcome at 3 assessment points: baseline, 3 and 6 months later. Current pain status was assessed at follow-ups. Patients were classified as those that met standard criteria for chronic pain or those who did not (i.e., the comparison group). At baseline, participants demonstrated a bias toward sensory pain words. However, biases toward sensory pain words did not differentiate those who subsequently developed chronic pain and those who did not at either follow-up. The same bias was observed 6 months later, but again it failed to distinguish between the chronic pain and comparison groups. However, subjects who developed chronic pain at both 3 (n = 22) and 6 (n = 21) months demonstrated biases away from affective pain words at baseline but not 6 months later, in comparison to other participants. These results remained significant in multivariate analyses. These findings are consistent with patterns observed in the previous research, and suggest that avoidance of emotionally laden pain-related stimuli (i.e., affective pain words) is associated with negative outcomes for LBP patients in the acute and sub-acute phase. This research suggests that attentional biases in relation to pain-related stimuli are important for the development of chronic pain, but are more complex than initially thought.     

Measuring practitioner/therapist effects in randomised trials of low back pain and neck pain interventions in primary care settings

In psychological health treatment studies it has been shown that differences between therapists account for some of the non‐specific effect of treatment but this phenomenon has not so far systematically been investigated in musculoskeletal disorders. In this study we evaluated and compared the size and potential influence of the ‘practitioner effect’ (or ‘therapist effect’) in three randomised treatment trials of low back pain and neck pain patients in primary care. We calculated the proportion of variance in outcomes attributable to differences across practitioners, i.e. the practitioner–variance partition coefficient (p–vpc). As measures of outcome, we focused on self‐reported disability as the primary outcome, but we also investigated assessed psychological outcomes. The p–vpc for the disability measures ranged from 2.6% to 7.1% across trials and time points (post treatment and follow up). Estimates differed between treatment subgroups within trials; being highest in treatment subgroups assigned to psychosocial‐based interventions. A ‘practitioner effect’ does exist and is more pronounced in treatments involving greater psychosocial emphasis. This has implications for both practice and research in this clinical area. It highlights the importance of patient–practitioner interactions, and the need to address practitioner effects in designing and analysing outcome studies in low back pain and neck pain in primary care.