Objective. To investigate the efficacy, safety, and impact on quality of life of long-term administration of OROS hydromorphone ER (8–128 mg) in patients with chronic low back pain.
Design. A total of 113 adults with chronic low back pain who completed a 6-week open-label study were enrolled in this 6-month extension study.
Outcome Measures. The primary end point was the daily pain relief rating obtained during monthly study visits. Secondary end points included Investigator and Patient Global Evaluations, Brief Pain Inventory scores obtained at monthly study visits, and quality-of-life measures (Medical Outcomes Study Questionnaire and 36-Item Short-Form Health Survey score) obtained at monthly intervals.
Results. Mean ± SD change from baseline in pain relief with OROS hydromorphone ER for the Month 6 visit was 0.9 ± 2.55 (P = 0.0007) and for the last assessment of the extension study was 0.9 ± 2.53 (P = 0.0002). At the Month 6 visit, 81.3% of investigators and 71.0% of patients rated their satisfaction of pain relief with OROS hydromorphone ER treatment as good, very good, or excellent. Changes on the 36-item Short Form Health Survey, a quality-of-life measure, were statistically significant for the physical composite scores for all extension phase time points, including Month 6 (2.1 ± 5.34; P < 0.0001) and the last assessment (2.4 ± 5.56; P < 0.0001) and mental composite scores for all extension phase time points, including Month 6 (3.3 ± 9.52; P = 0.0006) and the last assessment (3.1 ± 9.5; P = 0.0008). Treatment with OROS hydromorphone ER also resulted in significant improvement in sleep disturbances. Adverse events included gastrointestinal and central nervous system symptoms.
Conclusions. The results support the long-term use of OROS hydromorphone ER in managing chronic moderate to severe low back pain.