An observational study of health-related quality of life and pain outcomes in chronic low back pain patients treated with fentanyl transdermal system.

BACKGROUND: The analgesic effect of long-acting opioids, such as transdermal fentanyl, has been demonstrated in patients with cancer, neuropathic pain and chronic low back pain (CLBP). However, the broader effect of long-acting opioids on the patient's health-related quality of life (HRQoL) is less well known.

OBJECTIVE: To evaluate HRQoL outcomes in CLBP patients treated with transdermal fentanyl.

RESEARCH DESIGN AND METHODS: An observational study was conducted at 17 clinical centers in the US. Eligible patients had CLBP diagnosis for at least 3 months and were taking short-acting opioids chronically, and then initiated transdermal fentanyl treatment. Patients completed the Treatment Outcomes in Pain Survey (TOPS), which includes the SF-36 Health Survey, at baseline and > or = 9 weeks of treatment. The HRQoL burden of CLBP was determined by comparing CLBP patients' SF-36 scores to the general US population and low back pain patient norms. HRQoL outcomes were determined by comparing baseline and follow-up TOPS and SF-36 scores. Additionally, HRQoL outcomes were evaluated across patient groups stratified by changes in pain intensity ratings as measured by an 11-point numerical rating scale.

RESULTS: At baseline CLBP patients (N = 131) scored one-to-two standard deviations (SD) below age and gender adjusted SF-36 general population norms (MANOVA F = 127.1, p < 0.0001) and significantly lower than low back pain norms (MANOVA F = 125.3, p < 0.0001). At follow-up, significant improvement (p < 0.05) was observed on six of the SF-36 scales and both SF-36 summary measures and five of the six TOPS pain-related scales. The magnitude of change in scores in effect size units among these scales ranged from 0.17 to 0.80, which are considered small to large effect size changes. HRQoL score improvement was greatest among patients experiencing the greatest pain relief.

CONCLUSION: CLBP patients who chronically used short-acting opioids showed tremendous HRQoL burden. Favorable HRQoL outcomes were observed among patients who reported pain relief.