Breakthrough cancer pain: prevalence and characteristics in patients in Catalonia, Spain.

Breakthrough pain (BTP), a transitory exacerbation of pain superimposed on a background of persistent, usually adequately controlled pain, has been reported to occur in 50% to 75% of cancer patients. However, a 23% prevalence of BTP was recently reported in a study of Spanish patients with advanced cancers, showing probably a low detection rate of this clinical problem. The purpose of the present study was to determine the prevalence of BTP among oncology patients managed by palliative care teams in Catalonia, Spain, and to characterize the frequency, intensity, and treatment of BTP episodes. Sixty-two teams studied 397 patients on a predetermined index day. BTP was reported by 163 (41%) patients, with a total of 244 episodes (mean 1.5 episodes/patient/day). Mean (SD) intensity of BTP episodes was 7.3 (2.0), compared with 2.9 (2.7) for persistent pain (both 0-10 scales). Morphine was used to treat 52% of BTP episodes, while 25% were untreated. These findings indicate that BTP remains underrecognized and undertreated in Spain.