Can we treat psychological disorders by treating the physical symptoms of the disorder? That’s an interesting question, but it is a complicated matter to scientifically demonstrate a confident answer. Some therapists are bypassing the science and specifically endorsing such an interpretation for an “emerging” treatment for post-traumatic stress disorder (PTSD) – Dual sympathetic reset or block.
“Emerging” is in quotes for that is often a euphemism for a treatment that lacks sufficient evidence to demonstrate efficacy. When a treatment is described as “emerging” it seems to me that two things are being acknowledged. The first is that the treatment is unproven, or else it wouldn’t be an emerging treatment, it would be an established or proven treatment. The second is an assumption – that future evidence will support it. It’s similar to the optimistic use of the word “yet”, as in, this treatment has not been proven “yet”. That implies that it will be.
Language matters, and a neutral and more scientific approach would be to call it exactly what it is – experimental. If a treatment has not yet been studied scientifically, then it’s “untested”. It is important to recognize that experimental treatments, in the end, may not work – that’s why we are doing experiments. In fact, most experimental treatments do not ultimately work. This is a fact critical to science-based medicine.
Most such treatments have supporters who treat scientific research as a mere inconvenience, a box that needs to be checked on the inevitable path to widespread use. They often give away their bias by stating that the treatment is being studied to show “that” it works, or “how” it works rather than “if” it works. “If” a treatment works is the only important question until you demonstrate scientifically that it does.
When discussing that scientific research you also have to keep a lookout for similar euphemisms. The research for treatments that have not yet been adequately demonstrated to work is often called “encouraging”. My concern here is not so much that it’s not true – positive preliminary evidence is encouraging – but rather that “encouraging” is often presented as “inevitable” when in reality most preliminary encouraging research turns out to be wrong.
I also find it problematic when explanations are offered to explain “how” a treatment works (often with the phrase “thought to” – the treatment is thought to work through this mechanism) before we know if they work. I find it especially problematic when hand-waving explanations are given that are based on metaphors or simplistic neuroscientific notions.
The risk here is that an emerging treatment with encouraging preliminary evidence and semi-plausible mechanism of action will be prematurely adopted, creating a group of providers who now have a vested interest in the treatment, and patients convinced by what may be nothing more than placebo effects. This becomes a self-sustaining ecosystem that can thrive in the absence of scientific evidence. Research is then steered into pragmatic studies that are not designed to actually test efficacy. When evidence for lack of efficacy emerges, it is dismissed.
I have concerns that this is exactly the path that Dual Sympathetic Reset for PTSD is taking. Promoters are talking about the treatment as if it is fully established. The idea is to use a dual sympathetic block (dual sympathetic reset), a nerve block procedure involving the stellate ganglion, to treat anxiety and PTSD. This is an established procedure for some types of facial pain. The claim is that people who suffer from PTSD are hypervigilant and have an exaggerated startle response because their sympathetic “fight or flight” system is stuck in the on position. Blocking the stellate ganglion can “reset” or “reboot” the sympathetic nervous system back to its normal function.
That’s a nice story, but it is completely unproven. I find it a bit simplistic. It is also a setup for maximal placebo effects – an invasive procedure that may have some symptomatic relief. It is not surprising that the vast majority of “studies” of this treatment are little more than case reports or case series – purely anecdotal.
A 2023 review of the published evidence concluded:
“Despite the encouraging results, we remain cautious in interpreting the benefit of the technique due to the lack of sufficient standardized clinical trial data, heterogeneity in reported results, and the potential for bias in reporting. Future studies should focus on evaluating and addressing the technique’s effectiveness, safety, tolerability, and indications.”
Another review found only two randomized placebo controlled trials for dual sympathetic blocks for PTSD, one study was positive and the other study was negative. Both studies were small and should be considered preliminary.
Clearly what is needed is registered trials with randomized, double-blind, placebo-controlled design and with the power and rigor to address the main question of efficacy. I can be convinced there is a useful clinical effect here (even if I would not jump to the simplistic “reset” explanation) with that level of evidence, if it reliably replicates. But we are no where near that threshold of evidence.
Language used by responsible professions should reflect reality – this is an experimental treatment, and it should be treated that way. That means it should only be used with proper informed consent indicating its experimental nature, and ideally within the context of a clinical trial. What we are mostly seeing instead is the treatment being promoted as if its efficacy is established, based entirely on anecdotes.