Prevalence and characterization of breakthrough pain in patients with cancer in Spain: the CARPE-DIO study

We aimed to evaluate the prevalence, characteristics and impact of breakthrough pain (BTP) in patients with cancer attending the main specialties involved in the diagnosis and management of BTP in Spain using a multicenter, observational, cross-sectional, multidisciplinary study. Investigators had to record all patients seen at the clinic during 1 month, determine whether the patients had cancer pain, and apply the Davies algorithm to ascertain whether the patients were suffering from BTP. Of the 3,765 patients with cancer, 1,117 (30%) had cancer-related pain, and of these patients, 539 had BTP (48%, 95%CI:45–51). The highest prevalence was found in patients from palliative care (61%, 95%CI:54–68), and the lowest was found in those from hematology (25%, 95%CI:20–31). Prevalence varied also according to sex and type of tumor. According to the Alberta Breakthrough Pain Assessment Tool duration, timing, frequency, location, severity, quality, causes, and predictability of the BTP varied greatly among these patients. BTP was moderate (Brief Pain Inventory [BPI]-severity median score = 5.3), and pain interference was moderate (BPI-interference median score = 6.1) with a greater interference with normal work, general activity, and enjoyment of life. Patients with BTP showed a mean ± standard deviation score of 28.5 ± 8.0 and 36.9 ± 9.5 in the physical and mental component, respectively, of the SF-12 questionnaire. In conclusion, prevalence of BTP among patients exhibiting cancer-related pain is high. Clinical presentation is heterogeneous, and therefore, BTP cannot be considered as a single entity. However, uniformly BTP has an important impact on a patient’s functionality, which supports the need for early detection and treatment.