Prevalence and characteristics of breakthrough pain in patients receiving opioids for chronic back pain in pain specialty clinics.

OBJECTIVE

We sought to assess the prevalence and characteristics of breakthrough pain (BTP) in patients with chronic back pain.

DESIGN

Researchers utilized a telephone survey using a pain assessment algorithm. This report represents a subset of patients from a larger survey of 228 patients with chronic pain unrelated to cancer.

PARTICIPANTS

This study employed 117 subjects taking opioids for a primary diagnosis of back pain and receiving care at geographically dispersed pain treatment centers. Subjects had pain lasting at least six months and had "controlled" baseline pain.

RESULTS

Eighty-seven subjects (74 percent) experienced 93 types of BTP. The median number of BTP episodes per day was two; median time to maximum intensity was 10 minutes, and median duration was 55 minutes. Onset could not be predicted for 46 percent of pains. Eighty-three percent of subjects used shorter-acting opioids for BTP. Other medications used for pain included NSAIDs, antidepressants, anticonvulsants, skeletal muscle relaxants, intrathecal local anesthetics, and transdermal local anesthetics.

CONCLUSIONS

These patients with opioid-treated chronic back pain commonly experienced BTP, which often had a rapid onset and a relatively short duration and was difficult to predict. Opioids were the mainstay of pharmacologic therapy, but nonopioid analgesics and adjuvant analgesics were commonly used.