Predicting long-term disability in a sample of patientes with back pain: A 2-year prospective follow-up study

The predictive power of the Fear-Avoidance Model is well established. This paper presents a 2year prospective follow-up study with the aim of investigating whether back-pain-related disability was predicted by the following variables which were measured when back pain was acute: a) the initial level of pain-related disability; b) Perceived Pain Intensity; c) Depression; d) FearAvoidance Beliefs; e) Anxiety Sensitivity; f) Resilience; and g) Experiential Avoidance. With the same aim, two time-variant variables were measured when pain was chronic: a) Pain FearAvoidance; and b) Chronic Pain Acceptance. CONCLUSIONS METHOD INTRODUCTION The findings of the present study indicate that Pain-Related Disability over the 2-year period was significantly predicted by the level of Disability and Fear-Avoidance Beliefs at pain onset, as well as by changes in Pain Fear-Avoidance over this period. According to the results, although Perceived Pain Intensity at pain onset was initially included in the model, it ceased to be significant when Pain FearAvoidance was entered in the model. Thus, Perceived Pain Intensity was not significantly associated with pain-related Disability. This finding contradicts the results of previous studies that emphasized that pain itself is a threatening condition which can elicit escape and avoidance responses. According to this result, initial functional disability played a more prominent role than pain intensity in the transition from acute to chronic pain. Pain-related Disability over time was significantly predicted by Fear-Avoidance Beliefs. These results support the "socialbeliefs approach" which proposes that avoidance behavior can happen when normative fear-avoidance beliefs are present. Resilience was included in the present study as a predictive variable. In contrast to predictions and previous evidence showing that resilience may buffer the negative impact of pain, Resilience did not predict pain-related Disability over time. It must be taken into account that evidence on the protective role of resilience comes from cross-sectional studies alone or from studies in which the patients already had chronic pain; thus it may be the case that resilience plays a protective role once pain has become chronic, although it does predict disability at pain onset. In contrast to the results of several prospective studies, Chronic Pain Acceptance did not predict pain-related Disability over time. It must be emphasized that Chronic Pain Acceptance and Pain Fear-Avoidance were highly negatively correlated (r2 = -.85; r3= -.84, r4 = -.75; r4 = -.81). Both constructs — at least as measured in this study — seem to represent two sides of the same coin; thus, when both are included in the analysis it not surprising that one of them is excluded from the model. In Sum, the results highlighted the predictive power of the Fear-Avoidance Model. According to the results, Pain FearAvoidance —composed of Pain Catastrophizing, Pain Vigilance, and Pain Anxiety— significantly predicted Disability over time. Also, initial functional disability played a more prominent role than pain intensity in the transition from acute to chronic pain. These results showed that nonpsychopathological fear-avoidance beliefs grounded in the social health culture can account for disability across time. RESULTS PREDICTING LONG-TERM DISABILITY IN A SAMPLE OF PATIENTS WITH BACK PAIN: A 2-YEAR PROSPECTIVE FOLLOW-UP STUDY R. Esteve, C. Ramírez-Maestre, R. Bendayan, A. E. López-Martínez, G.T. Ruíz-Párraga & E. R. Serrano EFIC IX Table 1. Means (M), standard deviations (SD), and Pearson correlation coefficients for all predictor variables. Note.*P<.05; **P<.01. Table 2. Final model predicting disability (95 individuals, 374 observations) Note. S.E.: standard error. A sample of patients treated at 5 primary care centres was assessed when they were experiencing an acute back pain episode and subsequently at 6, 12, 18 and 24 months. INSTRUMENTS • The Resilience Scale (RS) • Anxiety Sensitivity Index (ASI) • Acceptance and Action Questionnaire (AAQ) • Pain Catastrophising Scale (PCS) • Pain Vigilance and Awareness Questionnaire (PVAQ) • Pain Anxiety Symptoms Scale (PASS) • Hospital Anxiety and Depression Scale (HADS) • Fear-Avoidance Belifes Questionnaire (FABQ) • Chronic Pain Acceptance Questionnaire (CPAQ), • Pain Intensity Index • RolandMorris Questionnaire (RMQ) To investigate the change in the outcome variable, linear mixed models (LMMs) were conducted using SAS PROC MIXED software package. REASONS FOR ATTRITION •35.54% did not reply to the phone calls •36.36% “had no time” •14.05% refused participation •9.91% Did not attend the appointments 4 times •3.31% moved away •0.83% died. The participants who completed the five assessment sessions were compared to those who did not complete follow-up; there were no significant differences. The final model summarized in Table 2 included the following variables: Disability1, Fear-Avoidance Beliefs and Pain Fear-Avoidance. Perceived Pain Intensity, Depression, Anxiety Sensitivity, Resilience, Experiential Avoidance, and Chronic Pain Acceptance were not significant and were therefore excluded from the model. [email protected]s