Breakthrough pain in patients referred to pain clinics: the Italian pain network retrospective study.

Introduction: Despite breakthrough pain (BTP) being one of the most severe forms of pain, there are no definitive data on its prevalence.

Methods: The authors performed a retrospective survey of the prevalence of BTP in consecutive patients in four Italian pain clinics, subsequent to application of an Italian law mandating detailed clinical records on pain characteristics, treatment, and results. Mean pain intensity was assessed with a numerical rating scale from 0 to 10.