Papers of the Week

Up to 40% of individuals who undergo total knee arthroplasty (TKA) experience some degree of pain following surgery Presurgical insomnia, has been identified as a predictor of postsurgical pain; however, modifiable presurgical behaviors related to insomnia have received minimal attention. The present study developed a 2-item sleep and pain behavior scale (SP2) to investigate a maladaptive sleep and pain behavior and is a secondary analysis of a larger, parent study. Patients (N = 109) completed SP2 at baseline and 12 months and questionnaires assessing sleep and pain at baseline (pre-TKA), 6-weeks, 3-, 6-, and 12-months post-TKA. SP2 demonstrated adequate preliminary psychometric properties. As hypothesized, even after controlling for baseline insomnia, pain, anxiety and other covariates, baseline SP2 predicted insomnia symptom severity at 6 weeks (β = 2.828), 3 (β = 2.140), 6 (β = 2.962), and 12 months (β = 1.835) and pain at 6 weeks (β = 6.722), 3 (β = 5.536), and 6 months (β = 7.677) post-TKA (ps < .05). Insomnia symptoms at 6-weeks post-TKA mediated the effect of presurgical SP2 on pain at 3 (95%CI: .024-7.054), 6 (95%CI: .495-5.243), and 12 months (95%CI: .077-2.684). This provides preliminary evidence that patients who cope with pain by retiring to their bed and bedroom have higher rates of post-surgical insomnia and pain and supports efforts to target this maladaptive sleep and pain behavior to reduce postsurgical pain.