Pain trajectories and possible predictors of a favourable course of low back pain in patients consulting musculoskeletal physicians in The Netherlands

Contextual factors in persistent severe back pain: A longitudinal analysis among German employees

BACKGROUND

Chronic back pain in employees compromises participation in social and daily activities, as well as work.

OBJECTIVES

To examine the severity of back pain after 2 years and identify factors predicting stagnation at this level of pain.

METHODS

Data were derived from a prospective cohort study with randomized sampling of insurants in the German Pension Insurance using a questionnaire at baseline and follow-up after 2 years. The sample consisted of middle-aged employees (45-59 years) with strong limitations due to back pain (Chronic Pain Grade III or IV), who had not applied for disability pension and did not use medical rehabilitation in the previous 4 years before baseline. Stepwise multivariable logistic regression models with backwards selection were used to identify relevant contextual factors in the stagnation of severe back pain.

RESULTS

Of 1208 persons with severe back pain at baseline, 48% had stagnated at that pain level after 2 years. Predictors of persistent severe back pain were older age, poorer general health, more additional disabling conditions, more depressive symptoms, caregiving burden, less pain-related self-efficacy and more fear avoidance beliefs.

CONCLUSIONS

In a high-risk subgroup with several co-existing conditions, this analysis highlights (mental) health, social and personal (contextual) factors associated with long-term unfavourable back pain progression.

SIGNIFICANCE

Back pain is a condition that often has a chronic or recurrent course, threatening participation in many areas of life. In this study it was found that the unfavourable condition of severe back pain can remain stable for long periods of time in a significant proportion of sufferers. Contextual factors (self-efficacy, fear-avoidance beliefs, caregiving burden) as well as additional health problems should be considered when identifying persons with stagnating pain courses.

The association of the STarT Back Screening Tool and type of leg pain with low back pain disability trajectories: a prospective cohort study

BACKGROUND

Multiple factors influence the recovery process of low back pain (LBP). The identification and increased knowledge of prognostic factors might contribute to a better understanding of the course of LBP. The purpose of this study is to investigate the association of the STarT Back Screening Tool (SBST) risk score and the type of leg pain (non-radiating LBP, referred non-radicular, and radicular radiating leg pain) with the disability trajectory (at baseline, the slope, and recovery at one year) in adults with low back pain.

METHODS

This is a prospective cohort study in 347 patients with low back pain who sought physiotherapy care at three primary care practices in the Netherlands. Linear mixed models were estimated to describe the association of the SBST risk score and the type of leg pain with disability at baseline, the slope in the disability trajectory, and at twelve months follow-up.

RESULTS

A medium/high risk score on the SBST is associated with higher baseline disability scores on the Oswestry Disability Index (ODI), faster initial recovery, and still a higher disability ODI score at 12 months follow-up. Non-radicular referred and radicular radiating leg pain were associated with worse baseline disability ODI scores in LBP. This association was not present for the initial recovery or at the 12 months follow-up.

CONCLUSION

The SBST is associated with the LBP recovery trajectory. The SBST might be a useful tool to predict the disability trajectory in a heterogeneous group of people with low back pain in primary care and might, therefore, be recommended in future clinical practice guidelines. The type of leg pain was not associated with the recovery trajectory of LBP. Future research might focus on evaluating different types of leg pain.

TRIAL REGISTRATION

Clinicaltrials.gov: 109,643.

Responsiveness and Minimal Important Change of the PROMIS Pain Interference Item Bank in Patients Presented in Musculoskeletal Practice

We evaluated the responsiveness of the Patient Reported Outcome Information System Pain Interference item bank in patients with musculoskeletal pain by testing predefined hypotheses about the relationship between the change scores on the item bank, change scores on legacy instruments and Global Ratings of Change (GRoC), and we estimated Minimal Important Change (MIC). Patients answered the full Dutch-Flemish V1.1 item bank. From the responses we derived scores for the standard 8-item short form (SF8a) and a CAT-score was simulated. Correlations between the change scores on the item bank, GRoC and legacy instruments were calculated, together with Effect Sizes, Standardized Response Means, and Area Under the Curve. GRoC were used as an anchor for estimating the MIC with (adjusted) predictive modeling. Of 1,677 patients answering baseline questionnaires 960 completed follow-up questionnaires at 3 months. The item bank correlated moderately high with the GRoC (Spearman's rho 0.63) and with the legacy instruments (Pearson's R ranging from .45 to .68). It showed a high ES (.97) and Standardized Response Means (.71), and could distinguish well between improved and not improved patients based on the GRoC (Area Under the Curve .77). Comparable results were found for the derived SF8a and CAT-scores. The MIC was estimated to be 3.2 (CI 2.6-3.7) T-score points. PERSPECTIVE: Our study supports the responsiveness of the PROMIS-PI item bank in patients with musculoskeletal complaints. Almost all predefined hypotheses were met (94%). The PROMIS-PI item bank correlated well with several legacy instruments which supports generic use of the item bank. MIC for PROMIS-PI was estimated to be 3.2 T-score points.