The nature of cancer pain: Comparisons of malignant and non-malignant pain

Jan Earl Warner, Purdue University

Abstract

Evidence is presented that indicates the Multiaxial Pain Inventory (MPI), (Kerns, Turk & Rudy, 1985) is a valid measure of pain severity and general affective distress in cancer pain patients. Comparing cancer pain outpatients with consecutive referrals of non-malignant pain outpatients, cancer pain patients are significantly older, have less intense pain, shorter duration of pain, less affective distress, less interference and a lower general activity level. Most of the differences found between the cancer pain group and the younger non-malignant pain group were also found in the comparisons between the cancer pain group and an age-matched non-malignant pain group. However, when comparing age- and severity-matched cancer pain and non-malignant pain groups, most of the differences between cancer and non-malignant pain groups became non-significant. Operant variables predict approximately one third of the variance of pain severity and interference from pain in both non-malignant pain groups and in a group of cancer pain patients with duration of pain of at least one year. Operant variables predict very little of the variance of intensity and interference in the cancer pain group with a shorter mean duration. Results suggest there is a link between duration of pain and relevance of operant variables to pain behavior. The results also suggest that distracting responses to pain, as measured by the MPI, may positively reinforce pain behaviors. Results from cancer pain and non-malignant pain groups are consistent with the cognitive-behavioral theory of pain proposed by Rudy, Kerns and Turk (1988). In this model perceived control and interference with activities mediate the relationship between pain severity and affective distress. Perceived control is the best predictor of affective distress in all groups. Relative to perceived control, pain severity, social support and duration of pain are relatively poor predictors of affective distress and quality of life in pain patients. Overall, results suggest that comparisons between cancer pain patients and non-malignant pain patients reveal few differences in the multidimensional nature of pain, when methodology controls for pain severity and duration of pain.

Degree

Ph.D.

Advisors

Swensen, Purdue University.

Subject Area

Psychotherapy|Mental health

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