The release reports on a study that tested a new type of implanted device for the treatment of chronic back and leg pain. It uses high-frequency electrical pulses, delivered directly to the spinal cord via implanted leads. The study compared this high-frequency form of spinal cord stimulation (SCS) to a more traditional approach that uses lower-frequency pulses. The main advantage of the new approach, according to the release, is that patients don’t feel an annoying tingling or buzzing sensation that’s associated with the traditional approach.
The release faithfully reports the outlines of the study in broad strokes and provides some of the outcomes in user-friendly terms. But there a lot of missing context that any reporter relying on the release should have been given. Notably, this was a company funded study run by investigators with close ties to the manufacturer of the device. The surgery required to implant the device can cause harms that weren’t mentioned. Finally, it’s not clear if this device is approved for use and if so, how much would it cost to have it implanted and would insurance cover that cost?
Many people have chronic pain that isn’t satisfactorily addressed with existing approaches. If a new device can improve on those existing therapies as is claimed in this release, many people would be interested to know about it. But along with offering the good news about potential benefits, release writers have an obligation to provide context that cuts the other way — whether that’s possible harms from the device, conflicts of interest among the researchers, or limitations to the study design. They also owe it to readers to present a full array of potential alternatives. This release sets up what seems to be a false choice between SCS and either surgery or narcotics. Patient can also try yoga, exercise, NSAIDS, and behavioral modifications — treatments that can work and have little cost and risk.
The news release doesn’t address the costs of newer, high-frequency SCS vs. traditional SCS. Since traditional SCS seems to be commonly used, it should be possible to provide some estimate of what the device and the implantation procedure cost. It would be nice if the release had also addressed potential insurance coverage for either device.
The release does a good job of putting some numbers on the potential benefits. For example, the release gives us the absolute number of pain patients in each group who experienced a 50% or greater reduction in symptoms.
“At three months, 85 percent of back pain and 83 percent of leg pain patients in the HF10 therapy group experienced a 50 percent reduction in pain or greater. Conversely, only 44 percent of back pain and 56 percent of leg pain patients in the traditional SCS group experienced a 50 percent reduction in pain.”
Of course, it’s worth noting that these are the findings after 3 months, and the study lasted for 12 months. However, it doesn’t look like the benefits were diminished too greatly with longer-term use of the device, so we’ll award a Satisfactory grade — even though it would have been preferable to also see the findings after a full year of use.
The story doesn’t address harms except to note that the high-frequency group had no paresthesia. The study that’s the basis for the release noted that “non-serious” study-related adverse events occurred in about 30% of patients in both groups. These included implant site pain and lead migration resulting in “surgical revision” (i.e. a second operation). But that begs the question: How can a second surgery be considered “non-serious”?
The release provides some details, noting that the researchers examined 171 patients with chronic back or leg pain who were implanted at 10 comprehensive pain treatment centers. We’re also told the study was the first long-term comparison of the two approaches. But the release skimps on some important information. On the one hand, the release never tells us that this was a randomized study — one of the strongest study designs for comparing the effectiveness of two treatments. But on the other, the release doesn’t acknowledge the fact that the study wasn’t blinded, which is a very serious limitation in a study to assess pain. The patients knew which treatment they were getting and the study researchers also knew which patients were getting high-frequency vs. traditional SCS. This knowledge has the potential to bias the results of the study. Moreover, the non-blinded researchers were free to change patient pain medicines as they saw fit, and neither the release nor the study gives data on these changes: this sort of thing is very likely to lead to spurious results.
We’re not saying the release needed to go into detail on every possible limitation of this study, but readers need some sense that there are limitations and drawbacks to a study such as this. The release didn’t provide that context.
The release succumbs to exaggeration, noting that “More than 1.5 billion people worldwide suffer from chronic pain, with lower back pain being the most frequent condition affecting 23 to 26 percent of the population.” The release should’ve kept the discussion limited to back and leg pain and the specific kind of patients who would be candidates for this device — not every person in the world who suffers from chronic pain. By throwing out such numbers, the release takes on a promotional tone — as if its purpose is to increase interest in the procedure from anyone with chronic back pain.
The release does not tell readers that the study was funded by the Nevro Corporation, which makes the device that was studied, nor that the study authors had ties to the company and other medical device makers.
The release mentions traditional SCS, opioids, and back surgery as other approaches to back pain, and notes that they have “limited effectiveness and commonly known side effects.” But we don’t think this is enough for a Satisfactory grade here. The options for treatment of back pain are much more diverse than just surgery, narcotics, and an implanted spinal cord stimulator, and so in a sense the release is offering a false choice. Other less invasive components of multimodal pain management strategy include exercise, physical therapy, yoga, NSAIDS (e.g. ibuprofen), and behavioral counseling.
It’s not clear from the release if this device is approved and available. It appears that it is.
The release says, “This is the first long-term study to compare the safety and effectiveness of high frequency and traditional SCS therapy for back and leg pain.”
Nothing over-the-top here. We’ve already commented on exaggeration in the Disease Mongering criterion above.