Prospective Study of 3-Year Follow-Up of Low-Dose Intrathecal Opioids in the Management of Chronic Nonmalignant Pain
Pain Medicine, 08/01/2012
Hamza M et al. – Low–dose intrathecal (IT) opioid can provide sustained significant improvement in pain and function for long–term follow–up in chronic noncancer pain.Methods
- This is a prospective, cohort long–term outcome study.
- The intervention was the implantation of DDS.
- A total of 61 consecutive patients (60% females, 40% males) with a mean age of 59.2 years and a mean duration of symptoms prior to implant of 6.2 years were referred for implant of DDS for severe intractable noncancer pain.
- After adequate patient evaluation, each underwent a trial with IT opioids. Three patients failed the trial and 58 patients were implanted.
- Follow–up was 36 months, with intervals at 6, 12, 18, 24, and 36 months.
- The Brief Pain Inventory was used for follow–up assessment criteria at baseline prior to implant as well as throughout the duration of the study.
- Outcome measures included self–reported pain scores (worst and average), functional improvement, and IT dose, and oral opioid consumption.
- The authors observed a statistically significant reduction in both worst and average pain from baseline (8.91 and 7.47 at baseline) throughout the duration of the study (4.02 and 3.41, respectively, at 36 months) (P = 0.012 and P < 0.001, respectively).
- The authors also documented a statistically significant improvement in physical and behavioral function.
- All subjects showed a significant reduction in the oral opioid consumption. The dose of IT opioids remained low and virtually unchanged for 36 months of follow–up: 1.4 morphine equivalent/day at 6 months and 1.48 at 36 months.
- Oral opioid averaged 128.9 mg of morphine equivalent/patient/day at baseline to 3.8 at 3 month and remained at the same level throughout the study.