Risk and protective factors in the clinical rehabilitation of chronic back pain

Factors associated with pain-related functional interference in people with chronic low back pain enrolled in a physical exercise programme: the role of pain, sleep, and quality of life

OBJECTIVE

To identify the factors associated with the pain-related functional interference level in people with chronic low back pain.

DESIGN

Cross-sectional.

SUBJECTS/PATIENTS

Chronic low back pain patients.

METHODS

Sociodemographic data, pain intensity, pain-related functional interference, physical functioning and fitness, sleep quality, anxiety and depression, social support, and health-related quality of life were recorded. Descriptive and bivariate analyses were performed. A linear regression model was carried out to identify the factors associated with the pain-related functional interference level.

RESULTS

99 participants were involved (mean age: 54.37 SD: 12.44; women: 67.7%). 37.4%, 27.3%, and 35.4% were classified into low, moderate, and high pain-related functional interference level groups, respectively. Higher pain-related functional interference was associated with higher pain intensity (β: 0.724; p = 0.026), worse sleep quality (β: 0.077; p = 0.012), worse quality of life (physical (β: -0.539; p < 0.001) and mental (β: -0.289; p < 0.001), and lower consumption of weak opioids (β: -3.408; p = 0.037).

CONCLUSION

Beyond the pain experience and intensity among people with chronic low back pain, several biopsychosocial factors associated with this condition has been identified. Furthermore, higher pain intensity, worse sleep quality, worse quality of life, and weak opioids' consumption have been related to the pain-related functional interference of this population.

Psychometric Properties of the Pictorial Pain Interference Questionnaire for Assessing Functional Interference in Chronic Low Back Pain

OBJECTIVE

To analyze the psychometric properties of the Pictorial Pain Interference Questionnaire (PPIQ) for evaluating functional interference in the population with chronic low back pain (CLBP).

DESIGN

Cross-sectional study.

SETTING

Rehabilitation Unit in a hospital.

PARTICIPANTS

Ninety-nine patients with CLBP.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Functional interference was assessed using PPIQ. The following data were also collected: sociodemographic data; pain intensity (Numeric Pain Rating Scale [NPRS]); physical functioning (30-s arm curl, 30-s chair stand [30CST], and timed Up and Go [TUG] tests), fitness (International Physical Activity Questionnaire); quality of life (Short-Form 12 Health Survey version 1 [SF-12v1]); sleep quality (Spanish-validated 12-item Medical Outcomes Study Sleep scale [12-MOS Sleep]); anxiety and depression (Hospital Anxiety and Depression Scale [HADS]); and social support (Duke-UNK Functional Social Support Questionnaire). Internal consistency was analyzed using Cronbach's alpha, structural validity using exploratory factor analysis (EFA), and discriminant and convergent validity using bivariate analysis.

RESULTS

Ninety-nine patients with CLBP were included (age [mean ± SD]: 54.37±12.44 y); women, 67.7%). The EFA extracted 2 factors: "physical function and "social and sleep," which explained 57.75% of the variance. Excellent internal consistency was observed for the overall PPIQ score (Cronbach's α=0.866). Convergent validity was observed between the PPIQ and other functional measures (ρ: 0.52 and -0.47 for the TUG and 30CST, respectively; P<.001) and with the following variables: physical and mental component summaries of the SF-12v1 (ρ: -0. 55 and -0.52, respectively (P<.001); anxiety and depression of the HADS (ρ: 0.47 and 0.59, respectively (P<.001); NPRS (ρ: 0.45; P<.001); and index 9 of the 12-MOS Sleep scale (r: 0.49; P<.001).

CONCLUSIONS

The PPIQ is a valid instrument with good psychometric properties for measuring functional interference in people with CLBP. This questionnaire appears to be a feasible alternative when language or communication barriers exist in CLBP population.

Psychosocial work characteristics and low back pain in daycare (nursery) workers in Japan: a prospective cohort study

BACKGROUND

Low back pain (LBP) is one of the most common musculoskeletal problems affecting daycare (nursery) workers. We aimed to identify the psychosocial factors influencing LBP in daycare workers.

METHODS

We conducted a prospective cohort study with a one-year observation period. The baseline sample was a convenience sample of 444 daycare workers from 34 daycare facilities in Nagoya, Japan, and its suburbs. All the data were collected through a questionnaire survey. The question "Where are you currently feeling LBP?" was used to determine whether the subjects suffered from LBP. We examined the prospective relationships of the psychosocial work characteristics, i.e., high job strain, low social support, effort-reward imbalance, and overcommitment, at baseline and LBP after one year. We used multiple logistic regression analyses to calculate the odds ratios of psychosocial work characteristics for the persistence and onset of LBP, adjusted for age, sex, body mass index, smoking, employment status, occupation, and working schedule.

RESULTS

At baseline, 270 (60.8%) subjects suffered from LBP. Of 208 who also gave information on LBP one year later, 176 (84.6%) suffered from the persistence of LBP. Low social support at baseline was significantly related to persistent LBP one year later. The incidence of persistent LBP was 89.9% and 80.0% among those with and without low social support at baseline, respectively. The adjusted odds ratio (95% confidence interval) of low social support at baseline for the persistence of LBP was 2.43 (1.01-5.87). Of 150 who were without LBP at baseline and provided information on LBP one year later, 45 (30.0%) suffered from the onset of LBP. None of the psychosocial work characteristics showed significant relationships with the onset of LBP one year later.

CONCLUSION

Low social support was related to the persistence, but not to the onset of LBP in a prospective cohort analysis among daycare workers in Japan. High job strain, ERI, or overcommitment did not show a significant prospective effect on LBP.

Stress and Pain. Predictive (Neuro)Pattern Identification for Chronic Back Pain: A Longitudinal Observational Study

Introduction

Low back pain (LBP) leads to considerable impairment of quality of life worldwide and is often accompanied by psychosomatic symptoms.

Objectives

First, to assess the association between stress and chronic low back pain (CLBP) and its simultaneous appearance with fatigue and depression as a symptom triad. Second, to identify the most predictive stress-related pattern set for CLBP for a 1-year diagnosis.

Methods

In a 1-year observational study with four measurement points, a total of 140 volunteers (aged 18–45 years with intermittent pain) were recruited. The primary outcomes were pain [characteristic pain intensity (CPI), subjective pain disability (DISS)], fatigue, and depressive mood. Stress was assessed as chronic stress, perceived stress, effort reward imbalance, life events, and physiological markers [allostatic load index (ALI), hair cortisol concentration (HCC)]. Multiple linear regression models and selection procedures for model shrinkage and variable selection (least absolute shrinkage and selection operator) were applied. Prediction accuracy was calculated by root mean squared error (RMSE) and receiver-operating characteristic curves.

Results

There were 110 participants completed the baseline assessments (28.2 ± 7.5 years, 38.1% female), including HCC, and a further of 46 participants agreed to ALI laboratory measurements. Different stress types were associated with LBP, CLBP, fatigue, and depressive mood and its joint occurrence as a symptom triad at baseline; mainly social-related stress types were of relevance. Work-related stress, such as “excessive demands at work”[b = 0.51 (95%CI -0.23, 1.25), p = 0.18] played a role for upcoming chronic pain disability. “Social overload” [b = 0.45 (95%CI -0.06, 0.96), p = 0.080] and “over-commitment at work” [b = 0.28 (95%CI -0.39, 0.95), p = 0.42] were associated with an upcoming depressive mood within 1-year. Finally, seven psychometric (CPI: RMSE = 12.63; DISS: RMSE = 9.81) and five biomarkers (CPI: RMSE = 12.21; DISS: RMSE = 8.94) could be derived as the most predictive pattern set for a 1-year prediction of CLBP. The biomarker set showed an apparent area under the curve of 0.88 for CPI and 0.99 for DISS.

Conclusion

Stress disrupts allostasis and favors the development of chronic pain, fatigue, and depression and the emergence of a “hypocortisolemic symptom triad,” whereby the social-related stressors play a significant role. For translational medicine, a predictive pattern set could be derived which enables to diagnose the individuals at higher risk for the upcoming pain disorders and can be used in practice.

Mobile diagnostics and consultation for the prevention of the metabolic syndrome and its secondary diseases in Brandenburg-study protocol of a regional prospective cohort study: the Mobile Brandenburg Cohort

BACKGROUND

The metabolic syndrome (MetS) is a risk cluster for a number of secondary diseases. The implementation of prevention programs requires early detection of individuals at risk. However, access to health care providers is limited in structurally weak regions. Brandenburg, a rural federal state in Germany, has an especially high MetS prevalence and disease burden. This study aims to validate and test the feasibility of a setup for mobile diagnostics of MetS and its secondary diseases, to evaluate the MetS prevalence and its association with moderating factors in Brandenburg and to identify new ways of early prevention, while establishing a "Mobile Brandenburg Cohort" to reveal new causes and risk factors for MetS.

METHODS

In a pilot study, setups for mobile diagnostics of MetS and secondary diseases will be developed and validated. A van will be equipped as an examination room using point-of-care blood analyzers and by mobilizing standard methods. In study part A, these mobile diagnostic units will be placed at different locations in Brandenburg to locally recruit 5000 participants aged 40-70 years. They will be examined for MetS and advice on nutrition and physical activity will be provided. Questionnaires will be used to evaluate sociodemographics, stress perception, and physical activity. In study part B, participants with MetS, but without known secondary diseases, will receive a detailed mobile medical examination, including MetS diagnostics, medical history, clinical examinations, and instrumental diagnostics for internal, cardiovascular, musculoskeletal, and cognitive disorders. Participants will receive advice on nutrition and an exercise program will be demonstrated on site. People unable to participate in these mobile examinations will be interviewed by telephone. If necessary, participants will be referred to general practitioners for further diagnosis.

DISCUSSION

The mobile diagnostics approach enables early detection of individuals at risk, and their targeted referral to local health care providers. Evaluation of the MetS prevalence, its relation to risk-increasing factors, and the "Mobile Brandenburg Cohort" create a unique database for further longitudinal studies on the implementation of home-based prevention programs to reduce mortality, especially in rural regions.

TRIAL REGISTRATION

German Clinical Trials Register, DRKS00022764 ; registered 07 October 2020-retrospectively registered.

What Influences Outcomes From Inpatient Multidisciplinary Pain Management Programs?: A Systematic Review and Meta-analysis

OBJECTIVES

Although inpatient multidisciplinary pain management programs (PMPs) are effective for chronic pain, not all patients benefit equally and there is limited evidence regarding predictors of outcome. This meta-analysis aimed to identify patient or program characteristics associated with outcomes from inpatient PMPs, and to examine the time course of effects following discharge.

MATERIALS AND METHODS

Medline, EBSCO, and Scopus were searched to identify articles reporting outcomes from inpatient multidisciplinary PMPs. Information was extracted on study design, participant and program characteristics, and outcomes. Effect sizes were computed for pain, physical function, depression, anxiety, and mental health outcomes. Study-level predictors of outcome were investigated with moderator analyses and meta-regression. A risk of bias assessment and sensitivity analyses were conducted and the GRADE criteria for prognostic studies were applied to assess confidence in findings.

RESULTS

In all, 85 studies (111 cohorts; 15,255 participants) were included. Three quarters of studies demonstrated low risk of bias. Larger effect sizes (for at least 1 outcome measure) occurred in studies where participants had more severe pain (greater intensity/longer duration), participants with alcohol or drug problems were not excluded, samples comprised mixed pain conditions, and programs included a cognitive component and/or a passive therapy component. Effect sizes for pain and physical function were maintained at follow-up, but effect sizes for depression and anxiety declined over time.

DISCUSSION

Inpatient multidisciplinary PMPs may be well suited to patients with severe or long-lasting pain. Programs should adopt broad patient inclusion criteria, and outcomes were similar for programs based on cognitive-behavioral versus mindfulness/acceptance-based therapies.

Relevance of a novel external dynamic distraction device for treating back pain

Low back pain is a common, expensive, and disabling condition in industrialized countries. There is still no consensus for its ideal management. Believing in the beneficial effect of traction, we developed a novel external dynamic distraction device. The purpose of this work was to demonstrate that external distraction allows limiting the pressure exerted in standing-up position on the lower intervertebral discs. Numerical and cadaveric studies were used as complementary approaches. Firstly, we implemented the device into a numerical model of a validated musculoskeletal software (Anybody Modeling System) and we calculated the lower disc pressure while traction forces were applied. Secondly, we performed an anatomical study using a non-formalin preserved cadaver placed in a sitting position. A pressure sensor was placed in the lower discs under fluoroscopic control through a Jamshidi needle. The intradiscal pressure was then measured continuously at rest while applying a traction force of 200 N. Both numerical and cadaveric studies demonstrated a decrease in intradiscal pressures after applying a traction force with the external device. Using the numerical model, we showed that tensile forces below 500 N in total were sufficient. The application of higher forces seems useless and potentially deleterious. External dynamic distraction device is able to significantly decrease the intradiscal pressure in a sitting or standing position. However, the therapeutic effects need to be proven using clinical studies.

Personalized Treatment Suggestions: The Validity and Applicability of the Risk-Prevention-Index Social in Low Back Pain Exercise Treatments

Background: The back pain screening tool Risk-Prevention-Index Social (RPI-S) identifies the individual psychosocial risk for low back pain chronification and supports the allocation of patients at risk in additional multidisciplinary treatments. The study objectives were to evaluate (1) the prognostic validity of the RPI-S for a 6-month time frame and (2) the clinical benefit of the RPI-S. Methods: In a multicenter single-blind 3-armed randomized controlled trial, n = 660 persons (age 18–65 years) were randomly assigned to a twelve-week uni- or multidisciplinary exercise intervention or control group. Psychosocial risk was assessed by the RPI-S domain social environment (RPI-S_SE) and the outcome pain by the Chronic Pain Grade Questionnaire (baseline M1, 12-weeks M4, 24-weeks M5). Prognostic validity was quantified by the root mean squared error (RMSE) within the control group. The clinical benefit of RPI-S_SE was calculated by repeated measures ANOVA in intervention groups. Results: A subsample of n = 274 participants (mean = 38.0 years, SD 13.1) was analyzed, of which 30% were classified at risk in their psychosocial profile. The half-year prognostic validity was good (RMSE for disability of 9.04 at M4 and of 9.73 at M5; RMSE for pain intensity of 12.45 at M4 and of 14.49 at M5). People at risk showed significantly stronger reduction in pain disability and intensity at M4/M5, if participating in a multidisciplinary exercise treatment. Subjects at no risk showed a smaller reduction in pain disability in both interventions and no group differences for pain intensity. Regarding disability due to pain, around 41% of the sample would gain an unfitted treatment without the back pain screening. Conclusion: The RPI-S_SE prognostic validity demonstrated good applicability and a clinical benefit confirmed by a clear advantage of an individualized treatment possibility.

Stress and Self-Efficacy as Long-Term Predictors for Chronic Low Back Pain: A Prospective Longitudinal Study

Purpose

Psychosocial variables are known risk factors for the development and chronification of low back pain (LBP). Psychosocial stress is one of these risk factors. Therefore, this study aims to identify the most important types of stress predicting LBP. Self-efficacy was included as a potential protective factor related to both, stress and pain.

Participants and Methods

This prospective observational study assessed n = 1071 subjects with low back pain over 2 years. Psychosocial stress was evaluated in a broad manner using instruments assessing perceived stress, stress experiences in work and social contexts, vital exhaustion and life-event stress. Further, self-efficacy and pain (characteristic pain intensity and disability) were assessed. Using least absolute shrinkage selection operator regression, important predictors of characteristic pain intensity and pain-related disability at 1-year and 2-years follow-up were analyzed.

Results

The final sample for the statistic procedure consisted of 588 subjects (age: 39.2 (±13.4) years; baseline pain intensity: 27.8 (±18.4); disability: 14.3 (±17.9)). In the 1-year follow-up, the stress types “tendency to worry”, “social isolation”, “work discontent” as well as vital exhaustion and negative life events were identified as risk factors for both pain intensity and pain-related disability. Within the 2-years follow-up, Lasso models identified the stress types “tendency to worry”, “social isolation”, “social conflicts”, and “perceived long-term stress” as potential risk factors for both pain intensity and disability. Furthermore, “self-efficacy” (“internality”, “self-concept”) and “social externality” play a role in reducing pain-related disability.

Conclusion

Stress experiences in social and work-related contexts were identified as important risk factors for LBP 1 or 2 years in the future, even in subjects with low initial pain levels. Self-efficacy turned out to be a protective factor for pain development, especially in the long-term follow-up. Results suggest a differentiation of stress types in addressing psychosocial factors in research, prevention and therapy approaches.

Psychosocial areas of worklife and chronic low back pain: a systematic review and meta-analysis

BACKGROUND

The aim of this review was to synthesize the evidence on the potential relationship between psychosocial work factors from the Areas of Worklife (AW) model (workload, job control, social support, reward, fairness, and values) and chronic low back pain (CLBP; unspecific pain in the lumbar region lasting 3 months or longer).

METHODS

We conducted a systematic literature search of studies in Medline, PsycINFO, Web of Science, and CINAHL (1987 to 2018). Three authors independently assessed eligibility and quality of studies. In this meta-analysis, we pooled studies' effect sizes using a random-effects model approach and report sample size weighted mean Odds Ratios (ORs).

RESULTS

Data from 18 studies (N = 19,572) was included in the analyses. We found no studies investigating associations between fairness or values and CLBP. CLBP was significantly positively related to workload (OR = 1.32) and significantly negatively related to overall job control (OR = 0.81), decision authority (OR = 0.72), and two measures of social support (ORs = 0.75 to 0.78), even in prospective studies. Skill discretion and reward did not significantly relate to CLBP. Moderation analyses revealed several variables (e.g., exposure time, mean age and sex) affecting these relationships.

CONCLUSIONS

Our results support employees' workload, job control, and social support as predictors of CLBP. In this line, these work factors should be considered when developing programs to prevent chronic low back pain. Future studies should apply measures of CLBP that are more precise, and investigate the full areas of work life (AW) factors in combination.

Psychosoziale Risikofaktoren in der Entstehung von chronisch unspezifischen Rückenschmerzen

Zusammenfassung. Chronisch unspezifische Rückenschmerzen (CURS) gehören international zu den häufigsten Schmerzphänomenen und können für Athletinnen und Athleten karrierelimitierend sein. Knapp ein Drittel der jährlichen Trainingsausfallzeiten werden auf CURS zurückgeführt. In der Entstehung von chronischen Schmerzen ist ein multifaktorielles Ätiologiemodell mit einem signifikanten Einfluss psychosozialer Risikofaktoren evident. Obwohl dies in der Allgemeinbevölkerung bereits gut erforscht ist, gibt es in der Sportwissenschaft vergleichsweise wenige Arbeiten darüber. Dieses Thema wird daher in drei Multicenterstudien und zahlreichen Teilstudien des MiSpEx-Netzwerks ( Medicine in Spine-Exercise-Network, Förderzeitraum 2011 – 2018) aufgegriffen. Entsprechend der Empfehlung einer frühzeitigen Diagnostik von Chronifizierungsfaktoren in der „Nationalen Versorgungsleitlinie Kreuzschmerz“, beschäftigt sich das Netzwerk u. a. mit der Überprüfung, Entwicklung und Evaluation diagnostischer Möglichkeiten. Der vorliegende Beitrag beschreibt die Entwicklung einer Diagnostik von psychosozialen Risikofaktoren, die einerseits eine Einschätzung des Risikos der Entwicklung von CURS und andererseits eine individuelle Zuweisung zu (Trainings)Interventionen erlaubt. Es wird die Entwicklungsrationale beschrieben und dabei verschiedene methodische Herangehensweisen und Entscheidungssequenzen reflektiert.

Diagnosis of psychosocial risk factors in prevention of low back pain in athletes (MiSpEx)

Background

Low back pain (LBP) is a common pain syndrome in athletes, responsible for 28% of missed training days/year. Psychosocial factors contribute to chronic pain development. This study aims to investigate the transferability of psychosocial screening tools developed in the general population to athletes and to define athlete-specific thresholds.

Methods

Data from a prospective multicentre study on LBP were collected at baseline and 1-year follow-up (n=52 athletes, n=289 recreational athletes and n=246 non-athletes). Pain was assessed using the Chronic Pain Grade questionnaire. The psychosocial Risk Stratification Index (RSI) was used to obtain prognostic information regarding the risk of chronic LBP (CLBP). Individual psychosocial risk profile was gained with the Risk Prevention Index - Social (RPI-S). Differences between groups were calculated using general linear models and planned contrasts. Discrimination thresholds for athletes were defined with receiver operating characteristics (ROC) curves.

Results

Athletes and recreational athletes showed significantly lower psychosocial risk profiles and prognostic risk for CLBP than non-athletes. ROC curves suggested discrimination thresholds for athletes were different compared with non-athletes. Both screenings demonstrated very good sensitivity (RSI=100%; RPI-S: 75%-100%) and specificity (RSI: 76%-93%; RPI-S: 71%-93%). RSI revealed two risk classes for pain intensity (area under the curve (AUC) 0.92(95% CI 0.85 to 1.0)) and pain disability (AUC 0.88(95% CI 0.71 to 1.0)).

Conclusions

Both screening tools can be used for athletes. Athlete-specific thresholds will improve physicians' decision making and allow stratified treatment and prevention.

Development of a risk stratification and prevention index for stratified care in chronic low back pain. Focus: yellow flags (MiSpEx network)

Introduction

Chronic low back pain (LBP) is a major cause of disability; early diagnosis and stratification of care remain challenges.

Objectives

This article describes the development of a screening tool for the 1-year prognosis of patients with high chronic LBP risk (risk stratification index) and for treatment allocation according to treatment-modifiable yellow flag indicators (risk prevention indices, RPI-S).

Methods

Screening tools were derived from a multicentre longitudinal study (n = 1071, age >18, intermittent LBP). The greatest prognostic predictors of 4 flag domains ("pain," "distress," "social-environment," "medical care-environment") were determined using least absolute shrinkage and selection operator regression analysis. Internal validity and prognosis error were evaluated after 1-year follow-up. Receiver operating characteristic curves for discrimination (area under the curve) and cutoff values were determined.

Results

The risk stratification index identified persons with increased risk of chronic LBP and accurately estimated expected pain intensity and disability on the Pain Grade Questionnaire (0-100 points) up to 1 year later with an average prognosis error of 15 points. In addition, 3-risk classes were discerned with an accuracy of area under the curve = 0.74 (95% confidence interval 0.63-0.85). The RPI-S also distinguished persons with potentially modifiable prognostic indicators from 4 flag domains and stratified allocation to biopsychosocial treatments accordingly.

Conclusion

The screening tools, developed in compliance with the PROGRESS and TRIPOD statements, revealed good validation and prognostic strength. These tools improve on existing screening tools because of their utility for secondary preventions, incorporation of exercise effect modifiers, exact pain estimations, and personalized allocation to multimodal treatments.