Independent effect of physical workload and childhood socioeconomic status on low back pain among health care workers in Denmark

Physical activity, fear avoidance beliefs and level of disability in a multi-ethnic female population with chronic low back pain in Suriname: A population-based study

BACKGROUND

Chronic low back pain (CLBP) is an important cause for reduced daily physical activity (PA) and loss of quality of life, especially in women. In Suriname, a middle-income country in South America, the relationship between PA and CLBP is still unknown.

AIMS

To assess the level of PA in women with CLBP of different ethnicity, and to identify whether fear avoidance beliefs (FAB), disability, co-occurring musculoskeletal pain sites and various sociodemographic and lifestyle factors were associated with self-reported PA.

METHODS

A cross-sectional community-based house-to-house survey was conducted between April 2016 and July 2017. The survey followed the Community Oriented Program for Control of Rheumatic Diseases methodology. Selection criteria were being female of Asian-Surinamese, African-Surinamese or of Mixed ethnicity and aged 18 or older, living in an urban area, and reporting CLBP. Data was collected on PA, FAB, disability, co-occurring musculoskeletal pain sites, CLBP intensity and sociodemographic and lifestyle factors.

RESULTS

Urban adult women with current CLBP (N = 210) were selected. Nearly 57% of the population met the WHO recommendation on PA, with work-related PA as the largest contributor to total self-reported PA. Most women showed low FAB scores (FABQ-Work ≤34 (96.2%) and FABQ-PA ≤14 (57.6%)) and low disability levels (Oswestry Disability Index ≤20 (62.4%)). An inverse association between total PA and FABQ-Work (OR = 0.132, CI: 0.023; 0.750) was found. In contrast, total PA had a significant, positive association with disability (OR = 2.154, CI: 1.044; 4.447) and workload (OR = 2.224, CI: 1.561; 3.167). All other variables showed no association with total PA.

CONCLUSION

This was the first study in Suriname reporting that 43.3% of urban adult women with CLBP were physically inactive. Total self-reported PA is influenced by FABQ-Work, average to heavy workload and moderate to severe disability. In this study, PA-Work was the major contributor to total PA. Therefore, future longitudinal studies should evaluate different types and aspects of PA in relation to CLBP management.

Socioeconomic status and occurrence of chronic pain: a meta-analysis

OBJECTIVE

To examine the association between socioeconomic status (SES) and the occurrence of chronic pain, defined as pain that persists or recurs for >3 months.

METHODS

We performed a structured search in Medline, Embase, WHO Global Index Medicus and Conference Proceedings Citation Index-Science databases to identify cohort and case-control studies on chronic pain and SES and its subgroups (SES combined index, educational level, income and occupational status). We extracted study characteristics, outcome measures and measures of association and their 95% CIs. Literature search, data extraction and risk of bias assessment were conducted by two independent researchers. We performed main and subgroup meta-analyses using random-effects model, and formally assessed heterogeneity and publication bias.

RESULTS

A total of 45 studies, covering a population of ∼175 000 individuals, were meta-analysed, yielding a pooled Odds Ratio (OR) of 1.32 (95% CI: 1.21, 1.44) and 1.16 (95% CI: 1.09, 1.23) for low and medium SES levels, respectively, compared with high level. We obtained similar results in all the subgroup analyses. Heterogeneity was generally moderate to high across strata, and some evidence of publication bias for low socioeconomic status was found.

CONCLUSION

Our results support a moderate increase in the risk of chronic pain for low and medium SES when compared with high SES, a feature that remained constant in all measures of exposure or outcome used. Further prospective research on populations from developing countries are needed to confirm our findings as the studies available for this meta-analysis were carried out exclusively in developed countries.

Childhood overweight and obesity and back pain risk: a cohort study of 466 997 children

OBJECTIVES

To assess the association between age, sex, socioeconomic group, weight status and back pain risk in a large general population cohort of children.

DESIGN AND SETTING

A dynamic cohort of children aged 4 years in the Information System for Research in Primary Care (SIDIAP) electronic primary care records data in Catalonia. Multivariable Cox models were fitted to explore the association between back pain and weight status categories according to the WHO 2007 growth reference groups (body mass index for age z-score). Models were adjusted for age, sex, socioeconomic status and nationality.

PARTICIPANTS

Children seen at age 4 years at paediatric primary care clinics between 1 January 2006 and 31 December 2013 and followed up until 31 December 2016 or age 15 years.

OUTCOME MEASURES

Incident back pain registered by paediatricians at primary care using the International Statistical Classification of Diseases and Health Related Problems, 10th Edition code M54.

RESULTS

466 997 children were followed for a median 5.0 years (IQR 5.1). In multivariable models, overweight and obesity increased back pain risk, with adjusted HRs of 1.18 (95% CI 1.09 to 1.27) and 1.34 (95%CI 1.19 to 1.51) for overweight and obesity, respectively. Females were at greater risk of back pain than males with adjusted HR 1.40 (95%CI 1.35 to 1.46). Adjusted HR was 1.43 (95%CI 1.33 to 1.55) for back pain in children from the most deprived socioeconomic groups compared with the least deprived socioeconomic groups.

CONCLUSIONS

Maintaining a healthy weight from an early age may reduce the prevalence of back pain in both children and adults. Overweight female children from deprived socioeconomic groups are at greatest risk of back pain and represent a target population for intervention.

A comparison of standard and compositional data analysis in studies addressing group differences in sedentary behavior and physical activity

BACKGROUND

Data on time spent in physical activity, sedentary behavior and sleep during a day is compositional in nature, i.e. they add up to a constant value. Compositional data have fundamentally different properties from unconstrained data in real space, and require other analytical procedures, referred to as compositional data analysis (CoDA). Most physical activity and sedentary behavior studies, however, still apply analytical procedures adapted to data in real space, which can lead to misleading results. The present study describes a comparison of time spent sedentary and in physical activity between age groups and sexes, and investigates the extent to which results obtained by CoDA differ from those obtained using standard analytical procedures.

METHODS

Time spent sedentary, standing, and in physical activity (walking/running/stair climbing/cycling) during work and leisure was determined for 1-4 days among 677 blue-collar workers using accelerometry. Differences between sexes and age groups were tested using MANOVA, using both a standard and a CoDA approach based on isometric log-ratio transformed data.

RESULTS

When determining differences between sexes for different activities time at work, the effect size using standard analysis (η² = 0.045, p < 0.001) was 15% smaller than that obtained with CoDA (η² = 0.052, p < 0.001), although both approaches suggested a statistically significant difference. When determining corresponding differences between age groups, CoDA resulted in a 60% larger, and significant, effect size (η² = 0.012, p = 0.02) than that obtained with the standard approach (η² = 0.008, p = 0.07). During leisure, results based on standard (age; η² = 0.007, p = 0.09; sex; η² = 0.052, p < 0.001) and CoDA (age; η² = 0.007, p = 0.09; sex; η² = 0.051, p < 0.001) analyses were similar.

CONCLUSION

Results and, hence, inferences concerning age and sex-based differences in time spent sedentary and in physical activity at work differed between CoDA and standard analysis. We encourage researchers to use CoDA in similar studies, to adequately account for the compositional nature of data on physical activity and sedentary behavior.

What Is the Effect on Obesity Indicators from Replacing Prolonged Sedentary Time with Brief Sedentary Bouts, Standing and Different Types of Physical Activity during Working Days? A Cross-Sectional Accelerometer-Based Study among Blue-Collar Workers

Introduction

The aim of the study was to investigate if (a) substituting total sedentary time or long sedentary bouts with standing or various types of physical activity and (b) substituting long sedentary bouts with brief sedentary bouts; is associated with obesity indicators using a cross sectional isotemporal substitution approach among blue-collar workers.

Methods

A total of 692 workers from transportation, manufacturing and cleaning sectors wore an Actigraph GT3X+ accelerometer on the thigh for 1–4 working days. The sedentary (sit and lie), standing, walking, and moderate to vigorous physical activity (MVPA) time on working days was computed using validated Acti4 software. The total sedentary time and uninterrupted sedentary time spent in brief (≤5 mins), moderate (>5 and ≤30 mins), and long (>30mins) bouts, were determined for the whole day and during work and non-work time separately. The obesity indicators, BMI (kg/m²), waist circumference (cm) and fat percentage were objectively measured. Isotemporal substitution modelling was utilized to determine the linear association with obesity indicators of replacing 30 min of total sedentary time or long sedentary bouts with standing, walking or MVPA and separately replacing 30 min of long sedentary bouts with brief sedentary bouts.

Results

Workers [mean (standard deviation, SD); age = 45.1 (9.9) years, BMI = 27.5 (4.9) kg/m², %BF = 29.6 (9.5), waist circumference = 94.4 (13.0) cm] sat for 2.4 hours (~32% of the measured time, SD = 1.8 hours) across the day during work period and 5.5 hours (~62% of the measured time, SD = 1.5 hours) during non-work period. Most of the sedentary time was accrued in moderate bouts [work = 1.40 (SD = 1.09) hours] during work and in long bouts during non-work [2.7 (SD = 1.4) hours], while least in long sedentary bouts during work [work = 0.5 (SD = 0.9)] and in brief sedentary bouts [0.5 hours (SD = 0.3)] during non-work. Significant associations with all obesity indicators were found when 30 min of total sedentary time or long sedentary bouts were replaced with standing time (~1–2% lower) or MVPA (~4–9% lower) during whole day, work, and non-work periods. The exception was that a statistically significant association was not observed with any obesity indicator when replacing total sedentary time or long sedentary bouts with standing time during the work period. Significant beneficial associations were found when replacing the long sedentary bouts with brief sedentary bouts (~3–5% lower) during all domains.

Conclusion

Replacing total sedentary time and long sedentary bouts, respectively, not only with MVPA but also standing time appears to be beneficially associated with obesity indicators among blue-collar workers. Additionally, replacing long sedentary bouts with brief sedentary bouts was also beneficially associated with obesity indicators. Studies using prospective design are needed to confirm the findings.

Organizing workplace health literacy to reduce musculoskeletal pain and consequences

Background

Despite numerous initiatives to improve the working environment for nursing aides, musculoskeletal disorders (pain) is still a considerable problem because of the prevalence, and pervasive consequences on the individual, the workplace and the society. Discrepancies between effort and effect of workplace health initiatives might be due to the fact that pain and the consequences of pain are affected by various individual, interpersonal and organizational factors in a complex interaction. Recent health literacy models pursue an integrated approach to understanding health behavior and have been suggested as a suitable framework for addressing individual, organizational and interpersonal factors concomitantly. Therefore, the aim of the trial is to examine the effectiveness of an intervention to improve health literacy (building knowledge, competences and structures for communication and action) at both the organizational and individual level and reduce pain among nursing aides.

Methods/design

The intervention consists of 2 steps: 1) Courses at the workplace for employees and management in order to organize a joint fundament of knowledge and understanding, and a platform for communication and action about pain prevention in the organization. 2) Organizing a fixed 3-weekly structured dialogue between each employee and her/his supervisor, with particular focus on developing specific plans to prevent and reduce pain and its consequences. This enables the workplace to generate knowledge about employee resources and health challenges and to act and convey this knowledge into initiatives at the workplace.

Discussion

Previous studies to improve health literacy have primarily targeted patients or specific deprived groups in health care or community settings. Recently the idea of the workplace as an arena for improving health literacy has developed emphasizing the organizational responsibility in facilitating and supporting that employees obtain basic knowledge and information needed to understand and take action on individual and occupational health concerns. The literature about workplace health literacy is very limited but points at the importance of educating employees to be able to access, appraise and apply health information and of organizing the infrastructure and communication in the organization. This study suggests a concrete operationalization of health literacy in a workplace setting. Results are expected published in 2016.

Childhood socioeconomic position and adult leisure-time physical activity: a systematic review

Regular leisure-time physical activity (LTPA) benefits health and is thought to be less prevalent in lower socioeconomic groups. Evidence suggests that childhood socioeconomic circumstances can impact on adult health and behaviour however, it is unclear if this includes an influence on adult LTPA. This review tested the hypothesis that a lower childhood socioeconomic position (SEP) is associated with less frequent LTPA during adulthood. Studies were located through a systematic search of MEDLINE, Embase, PsycINFO, CINAHL and SPORTDiscus and by searching reference lists. Eligible studies were English-language publications testing the association between any indicator of childhood SEP and an LTPA outcome measured during adulthood. Forty-five papers from 36 studies, most of which were European, were included. In most samples, childhood SEP and LTPA were self-reported in midlife. Twenty-two studies found evidence to support the review's hypothesis and thirteen studies found no association. Accounting for own adult SEP partly attenuated associations. There was more evidence of an association in British compared with Scandinavian cohorts and in women compared with men. Results did not vary by childhood SEP indicator or age at assessment of LTPA. This review found evidence of an association between less advantaged childhood SEP and less frequent LTPA during adulthood. Understanding how associations vary by gender and place could provide insights into underlying pathways.

Is objectively measured sitting time associated with low back pain? A cross-sectional investigation in the NOMAD study

Background

Studies on the association between sitting time and low back pain (LBP) have found contrasting results. This may be due to the lack of objectively measured sitting time or because socioeconomic confounders were not considered in the analysis.

Objectives

To investigate the association between objectively measured sitting time (daily total, and occupational and leisure-time periods) and LBP among blue-collar workers.

Methods

Two-hundred-and-one blue-collar workers wore two accelerometers (GT3X+ Actigraph) for up to four consecutive working days to obtain objective measures of sitting time, estimated via Acti4 software. Workers reported their LBP intensity the past month on a scale from 0 (no pain) to 9 (worst imaginable pain) and were categorized into either low (≤5) or high (>5) LBP intensity groups. In the multivariate-adjusted binary logistic regression analysis, total sitting time, and occupational and leisure-time sitting were both modeled as continuous (hours/day) and categorical variables (i.e. low, moderate and high sitting time).

Results

The multivariate logistic regression analysis showed a significant positive association between total sitting time (per hour) and high LBP intensity (odds ratio; OR=1.43, 95%CI=1.15-1.77, P=0.01). Similar results were obtained for leisure-time sitting (OR=1.45, 95%CI=1.10-1.91, P=0.01), and a similar but non-significant trend was obtained for occupational sitting time (OR=1.34, 95%CI 0.99-1.82, P=0.06). In the analysis on categorized sitting time, high sitting time was positively associated with high LBP for total (OR=3.31, 95%CI=1.18-9.28, P=0.03), leisure (OR=5.31, 95%CI=1.57-17.90, P=0.01), and occupational (OR=3.26, 95%CI=0.89-11.98, P=0.08) periods, referencing those with low sitting time.

Conclusion

Sitting time is positively associated with LBP intensity among blue-collar workers. Future studies using a prospective design with objective measures of sitting time are recommended.

Musculoskeletal disorders and occupational exposures: How should we judge the evidence concerning the causal association?

Musculoskeletal disorders (MSDs) affecting the back, upper and lower extremities are widespread in the general population, implying a variety of causal factors. Multiple causes are not mutually exclusive, and a high background rate does not preclude associations with specific factors that are uncommon in the general population. MSDs have well-documented associations with occupational ergonomic stressors such as repetitive motion, heavy lifting, non-neutral postures, and vibration. Organizational features of the work environment, such as time pressure and low decision latitude, may also play a role, at least by potentiating the effects of physical loading. Numerous systematic reviews have mostly concurred with these overall findings. Nevertheless, some continue to debate whether MSDs are sometimes work-related, even for those performing jobs with repetitive and routinized tasks, heavy lifting, and/or pronounced postural strain. This article discusses (1) some epidemiologic features of MSDs that underlie that debate; and (2) the question of what should appropriately be considered a gold standard for scientific evidence on an etiological question such as the health effects of a non-voluntary exposure, such as an occupational or environmental agent. In particular, randomized clinical trials have little relevance for determining the health effects of non-therapeutic risk factors.