Psychological, surgical, and sociodemographic predictors of pain outcomes after breast cancer surgery: a population-based cohort study.

Chronic postsurgical pain (CPSP) is a common postoperative adverse event affecting up to half of women undergoing breast cancer surgery, yet few epidemiological studies have prospectively investigated the role of preoperative, intraoperative, and postoperative risk factors for pain onset and chronicity. We prospectively investigated preoperative sociodemographic and psychological factors, intraoperative clinical factors, and acute postoperative pain in a prospective cohort of 362 women undergoing surgery for primary breast cancer. Intraoperative nerve handling (division or preservation) of the intercostobrachial nerve was recorded. At 4 and 9months after surgery, incidence of chronic painful symptoms not present preoperatively was 68% and 63%, respectively. Univariate analysis revealed that multiple psychological factors and nerve division was associated with chronic pain at 4 and 9months. In a multivariate model, independent predictors of CPSP at 4months included younger age and acute postoperative pain (odds ratio [OR] 1.34, 95% confidence interval [CI] 1.12 to 1.60), whereas preoperative psychological robustness (OR 0.70, 95% CI 0.49 to 0.99), a composite variable comprising high dispositional optimism, high positive affect, and low emotional distress, was protective. At 9months, younger age, axillary node clearance (OR 2.97, 95% CI 1.09 to 8.06), and severity of acute postoperative pain (OR 1.17, 95% CI 1.00 to 1.37) were predictive of pain persistence. Of those with CPSP, 25% experienced moderate to severe pain and 40% were positive on Douleur Neuropathique 4 and Self-Complete Leeds Assessment of Neuropathic Symptoms and Signs pain scales. Overall, a high proportion of women report painful symptoms, altered sensations, and numbness in the upper body within the first 9months after resectional breast surgery and cancer treatment.

Changes in chronic pain severity over time: the Chronic Pain Grade as a valid measure.

Our understanding of the natural history of chronic pain in the community is limited. This is partly due to the lack of a validated measure of chronic pain severity known to be responsive to change over time. The Chronic Pain Grade questionnaire has been shown to be valid and reliable for use in a general population as a self-completion questionnaire. However, its reliability and validity for use in longitudinal studies and its responsiveness to change over time has not yet been assessed. We undertook a postal survey designed to test the responsiveness and the validity of the Chronic Pain Grade questionnaire over time. A random sample of 560 chronic pain patients, aged 25 years and over was drawn from an existing cohort and stratified for age, gender and chronic pain severity. Subjects were re-surveyed by a postal self-completion questionnaire consisting of the Chronic Pain Grade and the SF-36 general health questionnaire, which is known to be responsive to change in health over time. To test whether changes in CPG scores correlated with changes in SF-36 scores, Spearman's rank correlation coefficients were calculated. A response rate of 86% was achieved for the follow-up study. The majority of SF-36 scores changed in the hypothesized directions. Changes in CPG scores were significantly correlated with changes in most of the SF-36 domains. We concluded that the CPG is a useful and valid objective instrument for measuring change in severity of chronic pain over time and could be used in longitudinal studies of chronic pain severity.