Background & Aims

The crucial role of patients’ treatment expectations in influencing treatment outcomes is increasingly recognized. Nevertheless, the role of treatment expectations in treatment outcomes of interdisciplinary multimodal pain therapy (IMPT) for chronic low back pain (CLBP) remains incompletely understood. Evidence suggests that higher positive treatment expectations entail better outcomes regarding pain intensity and disability in CLBP.1,2,3 However, existing knowledge is incomplete and research considering treatment expectations in dependence of other psychological variables, especially of depression as a common comorbidity, is lacking. The aim of the present prospective study was to elucidate whether individual treatment expectations were associated with pain intensity and disability, while exploring the role of depression as a putative mediator, as well as to assess if treatment expectations predict these therapy outcomes at three-month-follow-up in patients suffering from CLBP.

Methods

200 patients (68.5% female, 60.23+12.99 years of age) with CLBP undergoing an IMPT filled in a comprehensive questionnaire battery at admission (T0), at the end of the therapy (T1), and at a 3-month-follow-up (T2). Sociodemographic variables and clinical pain characteristics, especially pain intensity and disability, were assessed with the German Pain Questionnaire.4 Therapy expectations were recorded with the Therapy Expectation Questionnaire (TEX-Q).5 Depression was assessed with the Beck Depression Inventory Fast Screen (BDI-FS).6 Based on TEX-Q total scores, three subgroups were generated by a cluster analysis, yielding groups with low, moderate, and high expectations. To investigate the influence of therapy expectations and depression as a covariate on pain and disability, we conducted analyses of (co-)variance with repeated measures. The predictive value of treatment expectations for changes within pain outcomes was investigated by regression analyses.

Results

For pain intensity, analyses revealed a significant “group x time” interaction (p = 0.026). Post-hoc-tests indicated significant standardized mean differences (SMD) between groups. The group with low expectations differed from the group with high expectations at T1 (SDM = 9.73, p = 0.003) as well as at T2 (SDM = 11.99, p = 0.007), indicating that the low expectation group experienced higher pain intensity. Since 43% of patients reported clinically relevant depressive symptoms, depression was included as a covariate. The interaction remained significant, and depression had a significant effect (p < 0.001), in contrast to the group differences. For disability with the significant covariates pain intensity T0 and depression, no interaction, and no main effects for time or group were found. Regression analyses revealed that improved pain intensity (adj. R² = 0.16, p < 0.001) and disability (adj. R² = 0.29; p < 0.001) were significantly predicted by therapy expectation and depression.

Conclusions

Treatment expectations within the psychosocial treatment context demonstrably shape the experience of pain and contribute to interindividual differences in treatment outcomes. The present analysis is the first to identify treatment expectations as a significant predictor of improvements in disability in consideration of depressive symptoms in a routine inpatient IMPT clinic setting. Results of the present study suggest that treatment expectations in patients suffering from CLBP play an important role as significant predictors of treatment outcomes. High positive expectations were associated with better pain outcomes. Comorbid depressive symptoms emerged as a significant predictor, which explained more variability in outcomes than treatment expectations and thus play a major role in the treatment of pain patients. Results are the basis and have the potential for optimizing treatment expectations regarding personalized therapy.

References

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2.Kamper SJ, Kongsted A, Haanstra TM, Hestbaek L. Do recovery expectations change over time? Eur Spine J 2015a;24:218-26.
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4.Petzke F, Hüppe M, Kohlmann T, Kükenshöner S, Lindena G, Pfingsten M, Schneider K, Nagel N. [Handbook German Pain Questionnaire]. 2022.
5.Alberts J, Löwe B, Glahn MA, Petrie K, Laferton J, Nestoriuc Y, Shedden-Mora M. Development of the generic, multidimensional Treatment Expectation Questionnaire (TEX-Q) through systematic literature review, expert surveys and qualitative interviews. BMJ Open 2020;10:e036169.
6.Beck AT, Steer RA, Brown GK. BDI-FastScreen for Medical Patients. Manual. San Antonio, TX: The Psychological Corporation, A Harcourt Assessment Company, 2000.
7.Colloca L, Miller FG. Role of expectations in health. Curr Opin Psychiatr 2011; 24:149-55.
8.Vaegter HB, Thinggaard P, Høj Madsen C, Hasenbring M, Bloch Thorlund J. Power of words: Influence of preexercise information on hypoalgesia after exercise – randomized controlled trial. Med Sci Sports Exer 2020; 52(11):2373-79.

Presenting Author

Claudia G. Levenig

Poster Authors

Claudia Levenig

Dr.

Ruhr University Bochum

Lead Author

Topics

  • Specific Pain Conditions/Pain in Specific Populations: Low Back Pain