Summary: It works, better than a placebo, but at least right now there's no way most folks can pay for it .
In response to several requests, here is an essay about transcranial magnetic stimulation on the occasion of its new FDA indication. This is adapted from a letter I wrote to a colleague who was writing an essay on this FDA step.
As you know, rTMS is not new (repetitive Transcranial Magnetic Stimulation -- the "repetitive" is designed to distinguish this approach from the way it is used in research settings for other purposes, where the exposure is more brief) . Indeed, it has been under research as a treatment for depression for at least a decade. The "new news" here is that it just received an FDA indication. It has been in use in
for several years. Canada
Indeed, about seven years ago I requested and received a letter from the FDA confirming my impression that it could be used "off label" for the treatment of depression even back then. At that time, it had just been shown to be equivalent to ECT (electroconvulsive therapy) without the risks and side effects. That was very exciting. I was actually gearing up to buy a machine, for around $25,000, and add that to our services at the hospital where I was working at the time.
However, I am glad that I did not. I continued to watch the literature on this technique. For one thing, it has now been associated in case reports with the potential for inducing hypomania/mania. This was recently reviewed by Xia and colleagues (link) who noted that in the aggregate, those who received TMS, versus those who received sham treatment, showed no statistically greater likelihood of switching into hypomania. However, that is the same result we have seen in studies of antidepressants versus placebo, and this is not enough to let go of that concern. The case reports are relatively convincing that at least in a few individuals this could be a risk. (Light therapy appears to carry a similar risk, for comparison).
So that was the first problem: the IE the risk of this treatment being no better than antidepressants (in terms of risk) in bipolar disorder. The second problem is actually a much larger issue: how much is this going to cost? Until insurance companies decide to pay for it, the cost will come out of people's pockets. At first it doesn't look so bad: a 30 minute treatment. But in most research studies it was done every day or every other day, generally for at least many days if not several weeks. So the cost of this is going to be extremely high, certainly in the ballpark of ECT. That is pretty much out of reach for most working people, I think.
Therefore, one of the very unfortunate effects of this hoopla about the FDA indication is that it will raise hopes of a "new treatment" before people discover that it is completely unavailable to them because of cost. As you know, insurance companies will wait for years labeling a new treatment "experimental" so as not to have to pay for it. This is still the case with light boxes for light therapy, despite years of research and a virtually unequivocal acceptance of the method as a treatment for seasonally associated mood change. So we can expect that insurance companies will try to avoid paying for this as well, probably for years. Note that they are still not paying for VNS (vagus nerve stimulation), a very similar circumstance with a new technique that costs a lot of money.
You can imagine how this is going to work. A psychiatrist who is tired of the hard work of managing medication side effects while trying to get them to work is going to buy this new machine for $30,000 (or whatever it is going to cause now; probably more, with this new indication), and then restrict his or her practice to patients who can afford to pay $5,000 -$10,000 or more for a course of treatment with rTMS. It may well work. What then? more money? So far no one has shown that this treatment will lead to a lasting change. And most people with highly recurrent or severe depression antidepressants are generally continued for six months to one year at minimum, and in patients with highly recurrent depression, antidepressant treatment is ongoing. When ECT in such people is effective, it often must be continued on a "maintenance" basis, one session of ECT every month or so to prevent recurrence. At this point it appears likely that rTMS will require similar ongoing treatment, and thus additional expense.
What if insurance companies were forced, somehow, to pay for this? Can our medical care system afford that? The technique sounds great: almost no risk (the seizure issue is a very minor concern at this point, it appears); almost no side effects (the headache problem is really minor); and good results (no better than existing treatments, mind you, such as ECT, but at least better than a placebo; in some of the more recent studies, it did not perform as well as ECT). But already we cannot afford our health care system. Already our patients cannot get some of the most expensive treatments because attempts by payers to limit access. The advent of rTMS will not help that circumstance, and in my view could make it worse, by raising alarm about how much treatment for depression could cost.
I do think this technique actually works, mind you. The research studies over the years do seem compelling. It's the practicalities that are the problem. At this point, I don't think the technique is so clearly better than what we already have as to warrant me or any of my colleagues going out to buy the device and start offering it to patients. Now, if it was free, that would be a different story...
So, overall, what is happening right now is little more than a press release, which means that the real news right now is that a company is ready to make money. I know that sounds pretty cynical. Let's wait and see if someone comes up with some way to make this practical.