Arch Phys Med Rehabil. 2008 Jun;89(6):1011-5.
The relationship between repeated epidural steroid injections and subsequent opioid use and lumbar surgery.
Friedly J, Nishio I, Bishop MJ, Maynard C.
OBJECTIVES: To evaluate whether the use of epidural steroid injections (ESIs) is associated with decreased subsequent opioid use in patients in the Department of Veteran's Affairs (VA) and to determine whether treatment with multiple injections are associated with decreased opioid use and lumbar surgery after ESIs.
DESIGN: VA patients undergoing ESIs during the study period for specific low back pain (LBP) diagnoses were identified, and lumbar surgery and opioid use were examined for 6 months before and after
ESI. SETTING: National VA administrative data.
PARTICIPANTS: U.S. veterans (retrospective data analysis).
INTERVENTIONS: Not applicable.
MAIN OUTCOME MEASURES: Opioid use and lumbar surgery after ESIs.
RESULTS: During the 2-year study period, 13,741 different VA patients underwent an ESI for LBP. The majority of patients were using opioids before their ESIs (64%), as were the majority after their ESIs (67%). Of patients not on opioids before the ESIs, 38% were prescribed opioids afterward, whereas only 16% of people on opioids before the ESIs stopped using opioids afterward. Patients who received more than 3 injections were more likely than patients receiving fewer injections to start taking opioids after ESIs (19% vs 13%, P<.001) and to undergo lumbar surgery after ESIs (8.7% vs 6.3%, P=.003).
CONCLUSIONS: Opioid use did not decrease in the 6 months after ESIs. In this population, patients who received multiple injections were more likely to start taking opioids and to undergo lumbar surgery within the 6 months after treatment with ESIs. These findings are concerning because our data suggest that ESIs are not reducing opioid use in this VA population.
No no, it's much better than that -
1) It doesn't make clear, and therefore I am assuming, these were both blind and fluoroscopically guided epidurals
2) It doesn't distinguish between transforaminal, interlaminar, or caudal procedures
3) It compares >3 vs 3 or less, within a 2 year period, but does not discuss whether these were done in a series, or over time. One series of three which then needed an additional injection is thus lumped in the same category as patients that had one injection every six months
4) 35% of patients who were not on opioids pre-procedure received opioid prescriptions after - were these short term, post-procedure prescriptions, or were they chronic opioid users - they do not distinguish.
5) They measured those who d/c'd their opioid use, but did not look at whether opioid use was decreased, even if not discontinued.
6) If a patient got better after one or two injections, you would expect them to stop using opioids, right? You would expect that THEY would be the ones more likely to not need surgery, right? Not these guys - they expect that, if you needed more than three injections, you should reduce your opioid use, and so were surprised when that population was more likely to go onto surgery.
Admittedly, if you didn't get better after either one or a series of three injections, you would also probably need opiods or surgery, but to me, that just belies the basic problem of the premise of the study - the assumptions they made, definitions they used, and methods they chose to employ to answer their questions, were imprecise (I am being kind).
What is really interesting is that, despite what a mess this paper is, it was published. Now each time you get turned down for an ESI, this is yet another horrendously flawed study that is going to be included in ACOEM, ODG, etc, and you are going to have to take time to explain to the medical director of the insurance carrier why they should not pay attention to "peer reviewed literature". Better still, some genius is going to include this nonsense in a meta-analysis, and tell you that 30 out of 42 published articles on ESI's show they don't work (I am making those numbers up).
You can thank the Dr. Friedly, The PM&R Department at The University of Washington, the
Archives, and the Academy for adding to both of those particular headaches.