Pain related recall predicts future pain report

Abstract

It is frequently necessary for patients to undergo multiple painful medical interventions as part of their diagnosis and care. Predictors of future pain report have yet to be established although initial pain level, affect, and memory of the procedure are often implicated. The purpose of this research was to establish a predictive model of future pain reporting using a standardized experimental pain stimulus. Forty-three healthy subjects completed an initial forehead cold pressor task (Session 1) and an identical task nine months later (Session 2). Subjects also provided retrospective pain evaluations six months after Session 1. Hierarchical regression was used to identify predictors of Session 2 maximum pain intensity. Fifty-six percent of the total variance (p < .01) was accounted when Session 1 maximum pain intensity, Session 1 negative affect, and remembered maximum pain intensity were loaded together in the model. Only 1% of the variance was uniquely accounted by Session 1 maximum pain intensity (p = .38) while remembered maximum pain intensity uniquely accounted for 25% of the variance (p < or = .01) and Session 1 negative affect uniquely accounted for 17% of the variance (p < or = .01). An additional 13% of the variance was shared between Session 1 maximum pain intensity and remembered maximum pain intensity. The level of remembered Session 1 pain was significantly exaggerated from the initial pain report (p < or = .05) but not significantly different from the level of pain reported at Session 2. These findings provide strong evidence for a post-pain modulation phenomenon in which cognitive processes influence both pain recall and future pain reporting.