One-year trend in pain and disability relief recall in acute and chronic ambulatory low back pain patients.

Clinicians use patients' recall of pain and disability relief as indicators of therapeutic effectiveness. Recall can change over time, however, and is influenced by factors other than true relief, including current health status. We have determined the trend in the relative contribution of current pain/disability and actual relief (current-baseline score) to relief recall over the course of 1 year. Self-referred patients (n=1182) seeking treatment from primary-care medical doctors and chiropractors in community-based clinics were asked to record present pain and disability, as well as perceived relief at five follow-up time points from 2 weeks to 12 months after initial consultation for acute and chronic low back pain (LBP). Multiple regression analysis was performed at each time point and over the five follow-up time points. We found a clear logarithmic time trend of increasing dependence of pain relief recall on present pain (P<0.0001) and a concomitant pattern of decreasing dependence on actual pain relief (P<0.0001). The patterns are fairly consistent for acute and chronic patients. The principal independent predictor of perceived pain/disability relief appears to be present pain/disability with actual relief playing a smaller role at all time points (P<0.0001) except for disability relief recall at 2 weeks (P=0.103). The findings are robust in LBP sufferers. Complaint characteristics including LBP chronicity, sciatica, LBP history, and comorbidity; psychosocial variables including stress, depression, and well being; sociodemographics; and treating provider type are not important independent predictors of pain and disability relief recall in ambulatory LBP patients. Perceived relief is too weakly related to present pain and disability to be accurate enough for use as a clinical assessment tool for individual patients. Physicians may need to use objective relief data to give the patient a realistic idea of actual improvement.