Assessment of potential risk factors for new onset disabling low back pain in Japanese workers: findings from the CUPID (cultural and psychosocial influences on disability) study

Graph modeling of relational structures among functioning variables with low back pain: an exploratory analysis based on International Classification of Functioning, Disability and Health

BACKGROUND

Given the complex etiology, multidimensional impact, and widespread prevalence of low back pain (LBP), it is crucial to prioritize intervention targets based on understanding the relationships between functional impairments in patients. This prioritization maximizes the physical and psychological benefits for patients, and graph modeling holds promise in achieving these objectives.

AIM

The aim of this study was establishing a graphical model of functioning variables for LBP based on the International Classification of Functioning, Disability, and Health (ICF) to identify the most influential items (i.e., functioning variables) on the physical and mental well-being of patients. Exploring feasible intervention measures by understanding the dysfunction correlations among these variables.

DESIGN

Cross-sectional survey.

SETTING

Nine hospitals in Jiangsu Province, China.

POPULATION

Three hundred and six persons with LBP aged ≥18 years.

METHODS

All patients were assessed using the Comprehensive ICF Core Sets for LBP. The scoring system was converted to dichotomous data, with 1 indicating dysfunction and 0 indicating no dysfunction. In the graphical model, network parameters and the results of Item Response Theory modeling (as detailed in our other article) were used to determine the importance of items, while partial correlations were utilized to estimate the dysfunction correlations between functioning variables.

RESULTS

1) A total of 56 ICF items were located in the backbone structure of LBP, among which d430 (Lifting and carrying objects) occupied the most central position, followed by b126 (Temperament and personality functions). 2) In the main component of backbone structure, d430 has moderate dysfunction correlation with looking after one's health (0.6027), social norms, practices and ideologies (0.597), stability of joint functions (0.5759), and emotional functions (0.4078). b126 has moderate dysfunction correlation with basic interpersonal interactions (0.6595).

CONCLUSIONS

d430 and b126 significantly impact the physical and mental well-being of LBP patients. To improve d430, maintaining exercise habits, reducing working hours, enhancing lumbar stability, and overcoming fear-related emotions are recommended. Similarly, improving b126 can be achieved through enhancing interpersonal relationships.

CLINICAL REHABILITATION IMPACT

Through the identification of crucial functioning variables and the associated dysfunctional correlation relationships, graphical model of Comprehensive ICF Core Set for LBP can offer healthcare decision-makers valuable insights into potential treatment targets and pathways aimed at improving the condition of LBP patients.

The prevalence of disability and associated factors among community adults in the baseline of CHCN-BTH Cohort Study

BACKGROUND

Disability was a major public health problem in China. However, the prevalence of disabilities in community-dwelling adults and their relationships to chronic physical conditions were unclear. We aimed to estimate the prevalence of disabilities and associated factors among a large community-based cohort in China.

METHODS

Participants who were local permanent residents aged 18 years or above and completed the disability assessments were selected from the Cohort study on Chronic Disease of Communities Natural Population in Beijing, Tianjin and Hebei (CHCN-BTH) from 2017 to 2019. Disability was assessed using five questions about impairments and activity limitations based on the International Classification of Functioning (ICF), Disability and Health. Univariate, multivariate and multilevel logistic regressions were conducted to estimate the associations between disabilities and associated factors.

RESULTS

Totally, 12,871 community-dwelling adults completed the survey. Among of them, 12.9% (95% CI: 12.3%-13.5%) reported having any disability. The prevalence of any disability was significantly higher in participants who were older age, widowed, retired and smokers, had higher BMI, average monthly income < 5000 RMB, lower education level, lower physical exercise frequency and heavy physical labor. Multilevel logistic regressions showed that there were significant associations between disabilities with chronic physical conditions, especially in the vision impairment with lower back pain, and hearing impairment as well as difficulty walking without special equipment with injuries.

CONCLUSIONS

Many Chinese adults suffered from disabilities. Sustained efforts should be made to develop specific population-based health promotion and prevention programs for disabilities in China.

TRAIL REGISTRATION

ChiCTR1900024725 (25/07/2019).

Longer working hours and musculoskeletal pain: a meta-analysis

Objectives. Musculoskeletal pain is the most common health problem in the workplace, and one of the most important risk factors for this pain is longer working hours. This study aimed to investigate the association between long working hours and musculoskeletal pain. Methods. Based on the keywords, two scientific sources - PubMed and Embase - were reviewed. The time limit search included articles that were published until May 2020 and only studies published in English were eligible. The results of the studies were combined based on random effects and pooled odds ratio (OR) reported. The degree of heterogeneity in all analyses was investigated and reported based on χ² and I² tests. Publishing bias was also measured using statistical tests. Results. Longer working hours are associated with increased musculoskeletal pain with OR = 1.11 and 95% confidence interval (CI) [1.08, 1.14]. The result was OR = 1.52 and 95% CI [1.14, 2.03] in men and OR = 1.11 and 95% CI [1.00, 1.24] in women. Conclusion. Long working hours are an important and threatening factor for musculoskeletal health. Therefore, this issue should be considered in health policy as well as treatment and prevention.

Association of Low Back Pain with Shift Work: A Meta-Analysis

Shift work (SW) is the main working schedule worldwide, and it may cause sleep disorders, breast cancer, and cardiovascular disease. Low back pain (LBP) is a common problem in the workplace; however, the association between LBP and SW remains unclear. Therefore, we conducted a meta-analysis to determine the association between SW and LBP. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed, Embase, and Web of Science databases using a set of associated keywords were queried. The inclusion criteria were as follows: (1) adult employees hired by a company or organization; (2) SW exposure; and (3) the outcome of LBP according to examination or assessment. A total of 40 studies were included that met the inclusion criteria for the meta-analysis. SW was significantly associated with LBP (odds ratio [OR]: 1.31, 95% confidence interval [CI]: 1.18−1.47, p < 0.00001). Furthermore, it was observed that LBP was significantly associated with night shift (NS) (OR: 1.49, 95% CI: 1.24−1.82, p < 0.0001) but not with rotating shift (RS) (OR: 0.96, 95% CI: 0.76−1.22, p = 0.49). Moreover, LBP was significantly associated with SW in health care workers (HCWs) (OR: 1.40, 95% CI: 1.20−1.63, p < 0.0001) but not in non-HCWs (OR: 1.19, 95% CI: 0.94−1.50, p = 0.14). SW was significantly associated with LBP. Furthermore, the subgroup analysis showed that NS, but not RS, was associated with LBP. Compared with SW in non-HCWs, SW in HCWs was significantly associated with LBP.

Occupational status and self-reported low back pain by gender: a nation-wide cross-sectional study among the general population in Japan

Background

We aimed to examine the cross-sectional association between occupational class and self-reported low back pain (LBP) in a representative sample of the Japanese general population.

Methods

We used anonymized data from a nationwide survey (31,443 men and 35,870 women aged ≥ 20). Occupational class variables included working status, occupation, employment status, and company size (number of employees). Covariates included age, socio-economic status, lifestyle, and comorbidities. Poisson regression models stratified by gender were used to estimate adjusted prevalence ratio (APR) and 95% confidence interval (CI) for self-reported LBP.

Results

The prevalence of self-reported LBP was 11.7% in men and 14.2% in women. After adjustment for covariates and mutual adjustment for all occupational class variables, among both genders, agricultural/forestry/fishery workers and non-workers had a significantly higher prevalence of self-reported LBP: APR (95% CI) of agricultural/forestry/fishery was 1.36 (1.08–1.70) in men and 1.59 (1.30–1.93) in women; that of non-workers was 1.42 (1.18–1.70) in men and 1.23 (1.08–1.40) in women. Among men, non-regular employees were more likely to have self-reported LBP than regular employees: APR (95% CI) was 1.25 (1.07–1.46) in part-timers and casual staff and 1.18 (1.03–1.35) in other types of non-regular employees. Moreover, compared to men working at companies with ≥ 100 employees, men working at companies with 30–99 employees had a significantly higher prevalence of self-reported LBP (APR 1.17; 95% CI, 1.03–1.34). Among women, professionals and technicians (1.26; 1.11–1.43) and sales workers (1.22; 1.04–1.43) had a significantly higher prevalence of self-reported LBP than clerks. Neither employment status nor company size was associated with self-reported LBP in women. After stratified analyses by age group, similar patterns were observed in participants aged 20–64, but not in those aged ≥ 65.

Conclusion

Our results suggest that self-reported LBP is highly prevalent among agricultural/forestry/fishery workers and the unemployed, regardless of gender, and that there are also gender differences in the association of occupational class factors with self-reported LBP. It is necessary, therefore, to take preventive measures against LBP based on gender and occupational class factors in Japan.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12199-021-01031-2.

Effectiveness of fitness for work interventions for workers with low back pain: A systematic review

OBJECTIVES

Safety at work is important for workers with low back pain (LBP). This requires good job design that considers both worker capacities and work requirements, a concept called "Fitness for Work." This systematic review aimed to evaluate the effects of fitness for work interventions on workers with LBP.

METHODS

We searched PubMed, the Cochrane Library, and Scopus from 2000 through 2020, using relevant terms.

RESULTS

We reviewed nine randomized controlled trials (RCTs) out of 3052 unique references. All studies were RCTs conducted in Western countries. Some RCTs reported positive findings that fitness for work interventions were effective for LBP in facilitating shorter return to work time and reducing short-term sick leave. However, the results of the reviewed studies were inconsistent; therefore, there is insufficient evidence to draw firm conclusions about the effectiveness of fitness for work interventions. Furthermore, the interventions were not effective in reducing long-term sick leave over a 24-month period. There were consistent findings that fitness for work interventions were no more effective than control interventions on pain intensity, disability, and work ability of workers with LBP.

CONCLUSIONS

These results suggest that fitness for work interventions may be somewhat effective in facilitating return to work and preventing short-term recurrence in workers with LBP. However, workers need to carefully manage their condition to prevent long-term recurrence.

Lifestyle and subjective musculoskeletal symptoms in young male Japanese workers: A 16-year retrospective cohort study

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The SN/S and LBP risk was higher in the PL than in the GL group.

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Four positive predictors (life satisfaction, hours of sleep, exercise habits, physical fitness) are important factors.

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Health staff should advise on workers’ individual lifestyle.

This longitudinal study was conducted from 2002 to 2018 and aimed to investigate predictive lifestyle factors for the occurrence of subjective musculoskeletal symptoms. The participants came from several employers in Japan. Setting 2002 as the baseline, we performed logistic regression analyses using lifestyle questionnaire items as explanatory variables and Stiff neck/shoulders (SN/S) and Lower back pain (LBP) as objective variables (n = 16,748). Workers who responded positively to good lifestyle items with an odds ratio < 1.0 and those who did not were classified in the Good (GL) and Poor lifestyle groups (PL), respectively. The survival period between the groups was compared using the log-rank test and Cox hazard regression analysis with propensity score matching (n = 3,593). Based on the Cox hazard regression analysis results, the risk of SN/S was about 2.54 (95% confidence interval [CI]: 1.80–3.59) times higher for PL than for GL (p < 0.001). Similarly, after propensity score matching, the risk was about 2.33 (95% CI: 1.07–5.10) times higher for PL than for GL (p < 0.05). Further, LBP risk was about 2.45 (95% CI: 1.67–3.58) times higher for PL than for GL (p < 0.001). Similarly, after propensity score matching, the risk was about 3.50 (95% CI: 1.60–7.68) times higher for PL than for GL (p < 0.01). This study highlighted that workers with four good lifestyle factors (life satisfaction, hours of sleep, exercise habits, and physical fitness) presented reduced risk of subjective musculoskeletal symptom occurrence. To prevent musculoskeletal symptoms, physicians and occupational health staff should advise on workers’ individual lifestyle.

Preventive factors against work-related musculoskeletal disorders: narrative review

Musculoskeletal disorders (MSDs) are major causes of morbidity among workers. They comprise several signs and symptoms, as e.g. pain, paresthesia, fatigue and limited range of motion, which can be related to work tasks. Workplace-related factors include physical, psychological, social and biomechanical hazards. The main kinetic factors associated with MSDs include repetitive movements, exerting excessive force, awkward postures, compression and mechanical vibration. Accurate knowledge of epidemiological aspects, evaluation of ergonomic hazards and musculoskeletal symptoms, and workplace exercise may help reduce the occurrence of MSDs. The aim of the present review is to analyze the applicability of preventive strategies against MSDs among workers. We performed a narrative review based on a survey of databases PubMed and BIREME and included studies published in English, Spanish or Portuguese. We found that workplace exercise is beneficial for both employers and workers. Risk analysis of MSDs is essential for early identification of occupational hazards and to prevent health consequences and costs associated with absenteeism.

Sleep disturbances and back pain : Systematic review and meta-analysis

BACKGROUND

In today's society, sleep disturbances and back pain are both common problems which threaten health. Although some studies have focused on the effects of sleep disturbances on back pain, no meta-analysis has been done. The purpose of this study is to systematically review and perform a meta-analysis on the effects of sleep disturbances on back pain.

METHODS

A literature search in PubMed, Scopus and EMBASE with keywords until June 2019 was performed. The eligible articles were evaluated qualitatively and the results were pooled using random effects. The publication bias and the degree of heterogeneity were examined.

RESULTS

In all, 21 studies were included in the meta-analysis. Sleep disturbances were associated with back pain (odds ratio 1.52; confidence interval [CI] 1.37-1.68; P < 0.001). In men, the odds ratio was 1.49 (CI 1.34-1.65; P < 0.001). In women, the odds ratio was 1.56 (CI 1.33-1.81; P < 0.001). Begg's test (P = 0.856) and Egger test (P = 0.188) did not show any publication bias. A funnel plot and trim-and-fill method showed publication bias, and heterogeneity was also high.

CONCLUSIONS

Sleep disturbance is associated with risk of back pain. Improving sleep can be a deterrent against back pain. Therefore, interventions to reduce sleep disturbances can help to improve health. On the other hand, the relationship between sleep disturbances and back pain can be two-sided, and back pain can also lead to sleep disturbances. Not only in view of the lifetime prevalence and the multifactorial impairments of those affected, but also in consideration of social and economic burdens, this issue will remain of considerable importance.

The relationship between spinal pain and temporomandibular joint disorders in Korea: a nationwide propensity score-matched study

BACKGROUND

Patients with temporomandibular joint disorder (TMD) often complain of pain in other areas. Several studies have been conducted on spinal pain in TMD patients, but have contained only limited information. Therefore, this study analyzed the relationship between TMD and spinal pain in greater detail by using nationwide data.

METHODS

A total of 12,375 TMD patients from the Korean National Health Insurance Review and Assessment database were analyzed. Controls were selected using propensity score-matching. The McNemar test, chi-square test, and paired t-test were used to compare the prevalence and severity of spinal pain between cases and matched controls. Logistic regression and linear regression models were used to analyze factors affecting the prevalence and severity of spinal pain in patients with TMD.

RESULTS

The annual period prevalence of TMD was 1.1%. The prevalence was higher in younger individuals than in individuals of other ages and was higher in women than in men. The medical expenditure for TMD per person was $86. Among TMD patients, 2.5% underwent surgical procedures and 0.3% were hospitalized. The prevalence of spinal pain in patients with TMD was 48%, whereas that in the control group was 34%. Increased severity of TMD was associated with an increased probability of spinal pain. The medical expenditure, mean number of visits, and lengths of treatment for spinal pain were greater for patients with TMD than for controls ($136 vs. $81, 4.8 days vs. 2.7 days, 5.5 days vs. 3.3 days). Higher TMD grade was associated with greater differences in average medical expenditure, number of visits, and lengths of treatment for spinal pain between cases and controls. Additionally, for women, living in a rural area and having an older age and more severe TMD were associated with a greater probability of spinal pain and higher medical expenditure related to spinal pain.

CONCLUSION

A strong association was observed between the presence of TMD and the presence of spinal pain. The association became stronger as the severity of TMD increased, indicating a positive correlation between the severity of TMD and spinal pain.

Assessment of risk factors for non-specific chronic disabling low back pain in Japanese workers-findings from the CUPID (Cultural and Psychosocial Influences on Disability) study

The majority of patients with non-specific low back pain (LBP) suffer from chronic pain. Psychosocial factors play an important role in the chronicity of LBP. To explore the risk factors for chronic disabling LBP in detail, we assessed its various risk factors in Japanese workers, using data from the Cultural and Psychosocial Influences on Disability (CUPID) study. Data were drawn from a 1 yr follow-up of 20‒59 yr-old workers who participated in the CUPID study. A self-administered questionnaire assessed various factors, including individual characteristics, ergonomic work demands, and work-related or other psychosocial factors. Logistic regression analyses were performed to assess the associations between these factors and chronic disabling LBP. Of 198 participants, 35 (17.7%) had chronic disabling LBP during the 1 yr follow-up. Multivariate logistic regression analysis revealed that the interaction effect of the two factors, expectation of LBP problems and excessive working hours (≥ 60 h per week), was associated with chronic disabling LBP. Chronic disabling LBP was present in 42.5% of participants with both of these two risk factors, whereas it was present in 11.8% of participants without these risk factors. In conclusion, among various factors, the combination of two psychosocial factors was particularly associated with chronic disabling LBP.

Occupational Characteristics of Low Back Pain Among Standing Workers in a Japanese Manufacturing Company

Low back pain (LBP) is a major public health problem that adversely affects the quality of life (QOL) of workers. The etiology of LBP is considered to be multi-factorial with individual, physical, and psychosocial factors contributing to its development and persistence. Although prevention of LBP in workers in the workplace is very important, only a small number of studies have assessed the risk factors and epidemiology of LBP among Japanese factory workers who stand as part of their job. This cross-sectional study investigated the prevalence of LBP in 691 factory employees who conducted their work while standing. Health-related QOL was evaluated using the Roland-Morris Disability Questionnaire (RDQ) to quantify the severity of LBP with the aim of identifying risk factors for LBP among workers who stand as part of their work in an electronics manufacturing company. We observed that the prevalence of LBP lasting for at least 48 hours within a week was 20.0% among participants, with female employees and those with a prior history of LBP having a significantly increased risk of developing LBP. The distribution of the RDQ score showed a negative regression curve among the employees, which was different from the normal distribution pattern reported previously in Japanese patients with LBP. These findings suggest that prolonged standing among factory workers poses an increased risk for LBP.

Predictors for Nonspecific Low Back Pain in Rubber Farmers: A 1-Year Prospective Cohort Study

High prevalence of low back pain (LBP) has been reported among farmers. A number of contributing factors have been associated with LBP. However, predictors for LBP in this population are unknown. This longitudinally designed study aimed to identify the predictors of LBP in a sample of rubber farmers whose work involves heavy manual labor. Three hundred and twenty-seven rubber farmers, aged 18 to 70 years who reported no LBP in the previous year, were face-to-face interviewed and examined physically. The incidence of LBP was assessed monthly. The 12-month incidence of LBP in the cohort was 35%. Having a history of LBP (hazard ratio = 1.55, 95% confidence interval = 1.05-2.30) and an active job (hazard ratio = 1.98, 95% confidence interval = 1.16-3.40) were the predictors for the new onset of LBP in this sample. These 2 factors could therefore potentially be targeted to prevent or reduce the incidence of LBP in rubber farmers.

Subliminal (latent) processing of pain and its evolution to conscious awareness

By unconscious or covert processing of pain we refer to nascent interactions that affect the eventual deliverance of pain awareness. Thus, internal processes (viz., repeated nociceptive events, inflammatory kindling, reorganization of brain networks, genetic) or external processes (viz., environment, socioeconomic levels, modulation of epigenetic status) contribute to enhancing or inhibiting the presentation of pain awareness. Here we put forward the notion that for many patients, ongoing sub-conscious changes in brain function are significant players in the eventual manifestation of chronic pain. In this review, we provide clinical examples of nascent or what we term pre-pain processes and the neurobiological mechanisms of how these changes may contribute to pain, but also potential opportunities to define the process for early therapeutic interventions.