Success rates soared to 75% for patients who waited less than two years for a spinal cord stimulator implant, compared with 15% for patients whose who received implants 20 years after the onset of pain, according to a retrospective analysis. The length of time patients waited for a referral also varied by specialty, as shown in a scientific poster presented at the 30th Annual Meeting of the American Academy of Pain Medicine.
The study authors placed their findings in context by noting that fewer than 50% of patients currently report long-term success with spinal cord stimulator in the treatment of chronic pain. Improving wait times could significantly improve success rates, says lead author Krishna Kumar, Regina General Hospital in Regina, Saskatchewan, Canada.
“The success of spinal cord stimulation is time sensitive, in that as wait times decline, long-term outcomes with spinal cord stimulation are enhanced,” Kumar says.
Kumar cites barriers to referral that included lack of uptake and awareness among healthcare providers, patients and payers; ongoing reimbursement concerns; and fragmentation of pain-care delivery. Moreover, Kumar cites return to employment as a metric that has been unfairly employed to curtail access to spinal cord stimulation, a tactic he said downplays benefits of spinal cord stimulation for quality of life, pain and depression.
The study included 443 patients who received spinal cord stimulators. Beginning with the initial pain diagnosis, investigators examined points of delay to referral for implantation by primary care physicians and specialists. The effects on pain duration of gender, age, referring specialty, and their interactions were analysed using a two-way ANOVA. A multiple linear regression model that incorporated patient demographic characteristics and components of wait times was developed to predict factors responsible for delays in spinal cord stimulator implantation.
Patients first saw a physician an average of 3.4 months after developing a pain syndrome. Family physicians managed patients for 11.9 months. Specialists then took over management for an additional 39.8 months on average.
The mean time to implantation from symptom onset was 5.12 years. Neurosurgeons were quickest to make a referral, whereas, non-implanting anaesthetists were most likely to delay implantation. In fact, referral for spinal cord stimulator treatment took 2.15 years longer if a non-implanting anaesthetist vs. a neurosurgeon referred the patient.