A cross-sectional study on prevalence of pain and breakthrough pain among an unselected group of outpatients in a tertiary cancer clinic.

PURPOSE: Systematic knowledge about the prevalence and the treatment effects of cancer pain in patients attending a general oncology outpatient department is limited. The purpose of this study was to investigate the prevalence of pain in a large representative cohort of patients attending a general oncology outpatient department in order to guide further screening, classification, and treatment of pain.
MATERIAL AND METHODS: A cross-sectional study among patients visiting the outpatient clinic with histologically verified cancer, age≥18 years, adequate cognitive function, and no surgical procedures last 24 h were included. Pain was assessed by the Brief Pain Inventory and the Alberta Breakthrough Pain Assessment Tool.
RESULTS: Three hundred five patients were included. The mean age was 60 years, 94% had a WHO performance status of 0-1 and 59% received oncological treatment with a curative intent. The mean score for average pain last 24 h (numerical rating scale, 0-10) and current pain was 1.84 and 1.08, respectively. Twenty-two percent reported pain score of ≥4 as their average pain in the previous 24 h. Twenty-one percent reported breakthrough pain (BTP). In multivariate analyses, sleep, BTP, age, treatment intent, and comorbidity was significantly associated with mean average pain in the previous 24 h and explained 29% of the variability of average pain in the previous 24 h.
CONCLUSION: Of the patients at an oncology outpatient clinic, 22% reported clinically significant pain. These findings indicate that all patients are candidates to be screened for pain and, if present, a more detailed pain diagnosis should be established before any interventions can be recommended.