Exploring lower back pain related cardiovascular deconditioning in a working population

Abstract

Over the past few decades, the deconditioning paradigm proved to be a useful theoretical research model on low back pain (LBP). Physical deconditioning is not only seen as caused by LBP, but it also as a contributor to its chronicity. It is thought that deconditioned patients have decreased physical fitness such as a lower cardiovascular capacity. In the mechanism of deconditioning catastrophizing plays an important role. Experienced pain reinforces catastrophizing attitudes and avoidance behaviour, leading to deconditioning. However, evidence that people with LBP are showing deconditioning compared to age-matched controls is conflicting. Therefore it was our aim to analyse the relationship between LBP, catastrophizing and cardiovascular capacity (VO2peak). Subjects were employees from the Utrecht Police force, the Netherlands who were tested in a two year interval (N=825). Of the entire population two separate cohorts were analysed. The first cohort (N=116) consisted of subjects who reported LBP at baseline and either reported pain or no pain at follow-up. The second cohort (N=26) included subjects without LBP at baseline, but who reported LBP at follow-up; the ‘pain at follow-up group’. They completed questionnaires on LBP, pain catastrophizing (Pain Catastrophizing Scale, PCS), physical activity (the Short Questionnaire to Assess Health-enhancing physical activity, SQUASH) and completed two maximal exercise tests. Paired samples T-tests showed no changes in VO2peak over time in both cohorts. Student’s unpaired T-tests showed no differences in VO2peak between healthy subjects and subjects with LBP. Regression analysis yielded associations between VO2peak and gender, age, weight, PCS and SQUASH. Spearman’s correlations showed correlations between high intensity physical activity and pain and pain catastrophizing. It can be concluded that in LBP, pain and pain catastrophizing have a negative impact on high intensity PAL. However, this relationship did not significantly affect cardiovascular capacity in our population. Therefore, it is thought that staying active in the working process helps prevent cardiovascular deconditioning.