Björklund M.1,2, Svedmark Å.1, Wahlström J.3, Sommar J.4, Häger C.4
1Umeå University, Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå, Sweden, 2University of Gävle, Centre of Musculoskeletal Research, Gävle, Sweden, 3Umeå University, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine, Umeå, Sweden, 4Umea University, Umeå, Sweden
Background: Long-term neck pain is a common problem implying high societal costs. The evidence is only modest for any treatment and the relapse rate of neck pain is high. Therefore it is crucial to increase the understanding of potential risk factors. These include aspects of both physical and psychosocial workload, but the knowledge is so far scarce on how these factors are interrelated, how they influence potential treatment effects and relate to relapse of neck pain.
Purpose: The aim of the present study was to evaluate the effect of physical and psychosocial workload factors and perceived stress on treatment outcomes after an intervention period. A secondary aim was to determine whether the results differed between groups.
Methods: Ninety-seven working women, age 20-65 years, with long-term work-related neck pain participated in a treatment programme (Svedmark et al. 2016). They received 11 weeks of either tailored or non-tailored physiotherapy (pooled for the purpose of the present analysis) or treatment-as-usual in a randomized controlled trial with follow-ups at 3, 9 and 15 months. At follow-ups, we evaluated the impact of workload factors and stress on the trial outcomes pain intensity (Numeric Rating Scale, 0-10), neck disability (Neck Disability Index, 0-100) and quantity and quality of work performance (0-10). An ergonomist assessed physical workload factors at the 3-month follow-up using the Quick Exposure Check (QEC) assessment tool for neck and shoulder/arm work exposure. Psychosocial workload factors were assessed with seven subscales of the Nordic questionnaire for psychological and social factors at work (QPS Nordic). Perceived stress at work was assessed by a question from the QEC assessment (3 months) and by a complementary question of stress last month (all follow-ups). The associations of workload factors and stress with trial outcomes were analyzed with univariate regression (3 months), linear mixed model (3, 9 and 15 months, including group effects) and multivariate regression (3, 9 and 15 months). Factors with univariate associations of p 0.25 were included in multivariate analyses. Potential confounders (age, pain duration, BMI and physical activity) were included as covariates in the multivariate analyses.
Results: At the 3-month follow-up (univariate analyses) reduced decision control and work pace control (QPS Nordic) were associated to reduced work performance and increased disability, and decision control was also negatively related to pain. Stress at work and stress last month were associated to increased pain and neck disability, while stress last month was also negatively related to quality of work performance. The only physical variable associated with a negative outcome (reduced work performance) was shoulder work exposure. Multivariate longitudinal analyses are under way.
Conclusion(s): Psychosocial workload factors and perceived stress clearly influence the results of neck pain treatment intervention. Future studies on neck pain rehabilitation should therefore pay more attention to these factors in order to increase the likelihood of sustainable treatment results.
Implications: The findings imply that assessment of psychosocial workload and perceived stress are important to consider in the care of working women with neck pain.
Funding acknowledgements: Swedish Council for Working Life and Social Research (2009-1403), AFA Insurance (090288) and The Centre for Environmental Research (1152383).
Topic: Musculoskeletal: spine
Ethics approval: This study has been approved by the Regional Ethical Review Board, Uppsala, Sweden, March 2011 ref: 2011/081.
All authors, affiliations and abstracts have been published as submitted.
