Depression, anxiety, catastrophising, and fear-avoidance beliefs are some of the so-called “yellow flags” that predict a poor outcome in back patients. Many surgeons have difficulty assessing yellow flags, perhaps due to the complexity of existing instruments and time constraints during consultations. We developed a brief tool to allow the systematic evaluation of core flags. Data from 4 questionnaires (ZUNG depression (N=399); Hospital Anxiety and Depression Scale (Anxiety-subscale) (N=308); Pain Catastrophising (N=766); Fear Avoidance Beliefs (N=736)) were analysed to identify the respective single item that best represented the full scale score. The 4 items formed the “Core Yellow Flags Index” (CYFI). 1'768 patients completed CYFI and a Core Outcome Measures Index (COMI) preoperatively, and COMI 3 and 12mo later (FU).Background
Methods
Most people experience low back pain (LBP) at least once in their lifetime. A minority goes on to develop persistent LBP causing significant socioeconomic costs. Aim of this study was to identify factors that influence the progression of acute to persistent LBP at an early stage (Hilfiker et al. 2007). Prospective inception cohort study of patients attending a health practitioner for their first episode of acute LBP or recurrent LBP after a pain free period of at least six months. Patients were assessed at baseline addressing occupational and psychological factors as well as pain, disability, quality of life and physical activity, and followed up over six months. Baseline and follow-up questionnaires were based on the recommendations of the Multinational Musculoskeletal Inception Cohort Study (MMICS) Statement (Pincus et al. 2008). Variables were combined to the three indices ‘working condition’, ‘depression and maladaptive cognitions’ and ‘pain and quality of life’. The index ‘depression and maladaptive cognitions’ comprising of depression, somatisation, a resigned attitude towards the job, fear-avoidance, catastrophizing and negative expectations on return to work was found to be a significant baseline predictor for persistent LBP up to six months (OR 5.1; 95%CI 1.04–25.1). The diagnostic accuracy of the predictor model had a sensitivity of 0.54 and a specificity of 0.90. Positive likelihood ratio was moderate with 5.3, negative likelihood ratio 0.5. Overall predictive accuracy of the model was 81%. The area under the curve in receiver operating characteristic (ROC) analysis of the index was 0.78 (CI95% 0.65–0.92), demonstrating a satisfactory quality of discrimination. Psychological factors in patients with acute LBP in a primary care setting correlated with a progression to persistent LBP up to six months. The benefit of including factors such as ‘depression and maladaptive cognition’ in screening tools is that these factors can be addressed in primary and secondary prevention.
