Research

The Nordic Subpopulation Research Programme: prediction of treatment outcome in patients with low back pain treated by chiropractors - does the psychological profile matter?

Charlotte Leboeuf-Yde¹ , Annika Rosenbaum² , Iben Axén³ , Peter W Lövgren⁴ , Kristian Jørgensen⁴ , Laszlo Halasz⁵ , Andreas Eklund⁶ and Niels Wedderkopp¹

¹  The Department of Research, the Spine Center, Hospital Lillebælt, University of Southern Denmark, Denmark

²  Private practice, Linköping, Sweden

³  The Karolinska Institutet, Stockholm, Sweden

⁴  Private practice, Stockholm, Sweden

⁵  Private practice, Lund, Sweden

⁶  Private practice, Södertälje, Sweden

author email corresponding author email

Chiropractic & Osteopathy 2009, 17:14doi:10.1186/1746-1340-17-14

Published:	30 December 2009

Abstract

Background

It is clinically important to be able to select patients suitable for treatment and to be able to predict with some certainty the outcome for patients treated for low back pain (LBP). It is not known to what degree outcome among chiropractic patients is affected by psychological factors.

Objectives

To investigate if some demographic, psychological, and clinical variables can predict outcome with chiropractic care in patients with LBP.

Methods

A prospective multi-center practice-based study was carried out, in which demographic, clinical and psychological information was collected at base-line. Outcome was established at the 4^th visit and after three months. The predictive value was studied for all base-line variables, individually and in a multivariable analysis.

Results

In all, 55 of 99 invited chiropractors collected information on 731 patients. At the 4^th visit data were available on 626 patients and on 464 patients after 3 months. Fee subsidization (OR 3.2; 95% CI 1.9-5.5), total duration of pain in the past year (OR 1.5; 95% CI 1.0-2.2), and general health (OR 1.2; 95% CI 1.1-1.4) remained in the final model as predictors of treatment outcome at the 4^th visit. The sensitivity was low (12%), whereas the specificity was high (97%). At the three months follow-up, duration of pain in the past year (OR 2.1; 95% CI 1.4-3.1), and pain in other parts of the spine in the past year (OR1.6; 1.1-2.5) were independently associated with outcome. However, both the sensitivity and specificity were relatively low (60% and 50%). The addition of the psychological variables did not improve the models and none of the psychological variables remained significant in the final analyses. There was a positive gradient in relation to the number of positive predictor variables and outcome, both at the 4^th visit and after 3 months.

Conclusion

Psychological factors were not found to be relevant in the prediction of treatment outcome in Swedish chiropractic patients with LBP.