Fear of pain in patients with advanced cancer

Pain is one of the most prevalent symptoms in patients with advanced cancer and, according to anecdotal evidence, perhaps the most feared. Surprisingly, fear of pain has been the subject of little research within cancer care. On the other hand, there is a large literature in the area of chronic non-malignant pain that is relevant to this issue. It suggests that fear of pain contributes to pain severity and to limitations in daily activities in various populations with chronic non-malignant pain. However, little is known about the extent to which such findings might generalize from patients with chronic nonmalignant pain to those with chronic cancer pain. Therefore, this research examined the extent to which fear of pain is associated with functional limitations in patients with advanced cancer. In particular, this study compared patients with chronic cancer and non-cancer pain on measures of fear of pain and other related constructs. The primary objective was to investigate, among patients with chronic pain due to advanced cancer, the relationships between fear of pain, catastrophizing, anxiety sensitivity, depression, physical symptoms, pain severity, and limitations in function. A secondary objective was to compare the relationship observed in cancer patients to those observed in patients experiencing chronic non-malignant pain. A total of 235 patients with chronic pain were recruited (117 patients with advanced cancer who received a referral for pain management and 118 patients with a primary complaint of chronic non-malignant pain). Participants completed self-report questionnaires. Findings revealed similarities between the groups for fear of pain, catastrophizing, anxiety sensitivity, physical symptoms, and limitations in function however, they differed on level of depression and pain severity. Fear of pain and catastrophizing independently predicted disability in both groups fear of pain predicted pain severity in patients with non-malignant pain. Catastrophizing predicted pain severity in both groups. Fear of pain mediated the relationship between anxiety sensitivity and limitations in function. This study provides an empirical perspective on fear of pain and other psychological constructs among patients with advanced cancer it integrates the literature on cancer and non-cancer chronic pain, and confirms the value of psychological adjuncts to pain management in cancer.