Autobiographical memory predicts postsurgical pain up to 12 months after major surgery

Recent cross-sectional studies have identified differences in autobiographical memory (AM) among individuals with chronic pain, but the temporal relationship between the 2 is unknown. Moreover, AM has yet to be studied in patients undergoing major surgery. This study addressed these gaps by conducting a prospective, longitudinal study of memory performance, postsurgical pain, and psychosocial factors in 97 adult participants scheduled for major surgery. Memories were evaluated using the Autobiographical Memory Test before and one month after surgery when participants were asked to recall personal events related to positive and pain-related word cues. Responses were coded for level of specificity, emotional valence, and surgery-related content. Questionnaires assessing presence/absence of pain and psychological functioning were administered before and at 1-, 3-, 6-, and 12-month follow-ups. Generalized estimating equations modelled pain at each postsurgical time point with memory variables as predictors. As hypothesized, higher numbers of specific pain memories recalled before surgery predicted lower odds of pain across all time points (OR = 0.58, 95% CI [0.37-0.91]). Participants who took longer to recall pain memories before surgery (OR = 2.65, 95% CI [1.31-5.37]) and those who produced more surgery-related content at the one-month assessment (OR = 1.31, 95% CI [1.02-1.68]) had greater odds of reporting postsurgical pain up to 12 months later. These findings indicate that presurgical AM biases are risk factors for development and maintenance of postsurgical pain. To the extent that these biases are causal, presurgical interventions that modify the quality and content of patients' memories may prove to be promising strategies in the prevention of chronic postsurgical pain.