Around 20 percent of primary care patients report having persistent pain. Although pain is one of the most common reasons for consultation with a physician, the condition is difficult to treat, and patients frequently are dissatisfied with conventional medical care. Legal regulations, prejudice, and continuing ignorance limit use of the most effective agents in cancer pain management—opioids. Studies in patients with cancer have found better pain control and improved quality of life with transdermal fentanyl compared to sustained-release oral morphine. Allan and colleagues compared transdermal fentanyl to sustained-release oral morphine in patients with noncancer chronic pain in a large, multicenter, two-way, crossover trial.
Patients requiring continuous potent opioids to treat chronic noncancer pain were recruited from 35 specialist pain clinics in seven countries. Standardized assessments of pain and quality of life were completed after each treatment and at the end of the study as part of the comprehensive assessment. The 256 patients were randomly assigned to initial treatment with sustained-release oral morphine or transdermal fentanyl in individualized doses calculated from the requirement for opioid immediately before the patient entered the trial. After four weeks, the treatments were reversed for a second treatment period of four weeks.
Data were available for 212 patients who completed the study. Transdermal fentanyl was preferred, or very much preferred, by 138 patients (65 percent) compared with 59 patients (28 percent) who preferred oral morphine. Average pain intensity scores were significantly lower during fentanyl treatment. A significantly higher proportion of patients reported good or very good pain control during fentanyl treatment (35 percent compared with 23 percent). The type of pain did not influence the results.
Patients also reported higher quality of life scores during fentanyl therapy in the overall scores, and in categories such as bodily pain, vitality, social functioning, and mental health. The incidence of adverse effects was similar in both groups, with more than 70 percent of patients reporting adverse effects. Serious adverse effects were less common during fentanyl therapy; nausea was more common and constipation less common during fentanyl therapy than during morphine treatment. More patients withdrew during fentanyl therapy than during morphine therapy. The percentage withdrawing because of adverse effects (11 percent) during fentanyl therapy was double that during morphine therapy.
The authors conclude that transdermal fentanyl therapy provides superior pain relief and is associated with enhanced quality of life compared to oral morphine in patients with chronic noncancer pain.