Is Heat an Antidepressant?

The historian in me says, wait a minute...

Posted May 15, 2016

In the attached blog, you’ll see two very astute psychiatrists cast doubt on a recent study in JAMA Psychiatry – a  prestigious mental-health journal – on research helmed by Clemens Janssen, at the University of Wisconsin-Madison, showing that hyperthermia seems to be an antidepressant: Putting depressed patients in a heat-box for a period of time had a beneficial effect on their mood disorder. They became clearly less depressed than a control group that received only mild, presumably non-therapeutic heat.

This blog piece represents science at its best: looking at a startling new finding very closely to see if it realty does establish what it purports to. Most observers, myself included, would be inclined to doubt this new finding: putting people with depression in a hot-box is therapeutic, really?

But what if it’s true (even though the authors made a big statistical error)?

In psychiatry today, the only two therapies considered worthwhile are psychotherapy and pharmacotherapy. Both are relatively recent. Psychotherapy took off only in the 1920s as Freud’s psychoanalysis became the great vogue (although psychotherapy does begin in the 1880s). And pharmacotherapy became the mainstay of psychiatric treatment only in the 1950s – and it took decades for drugs to knock Freud off the pitcher’s mound.

But before these two recent therapies there was a third therapeutic tradition in psychiatry – and it involved heat. And it was very successful.

It was the so-called “physical-dietetic therapies” that were administered in spas and in the private nervous clinics of the big cities. In those days, “spa” meant not a place where you went to lose weight and eat kale leaves but clusters of small luxury hotels on top of hot springs. Sarasota Springs in the US, Baden-Baden in Germany: these were spas.

The patients who went to them had largely what we would call “depression,” although it was known in the day as “nervous illness” or “psychoneurosis.”  And they were treated by clinicians who today would be psychiatrists, although, again in the day, they were known as neurologists and spa-specialists (psychiatrists were found only in asylums).

At the spas, there was lots of heat therapy: the warm springs fed hydrotherapy installations where you could soak for hours at a time. There were hot sprays, hot rubs and packs.

The attached blog piece contains a photo of a hot-box used in Janssen’s research. But the spas had hot-boxes too, cabinets lined with electric light bulbs where you would sit, your head poking out, and get your temperature stoked up.

All this was very successful. The psychiatry of the day had no effective drugs (aside from the barbiturate sedatives, introduced around 1900). But who needed to be drugged when you could sit in a hot pool and then have a lovely lunch afterwards served in one of the hotel restaurants with a nice linen tablecloth, gleaming table silver, and the spa orchestra playing nearby on the local green.

This, too, is effective antidepressant therapy, and it does not involve such side effects as losing your sex life, constipation, or blurred vision.

And then, all of a sudden, we lost track of this third therapeutic tradition, the tradition of spa therapy and physical therapy in psychiatry. The psychopharmacologic revolution of the 1950s made it appear quaint; the talk therapy of psychoanalysis made spa therapy sound useless, raising your body temperature instead of lying on the couch free-associating; and the poverty and destitution of the war years in Europe wiped out much of the middle class, so that people could no longer afford to spend two weeks at a time getting hydrotherapy.

Psychiatrists today know nothing of this tradition; specialists of physical therapy are vaguely familiar with it, although it has vanished in North America, and hangs on by a thread in Germany, France and northern Italy, where family memories linger of summering in Vichy or Bad Kissingen. Indeed, physical therapy might be added to the list of things that psychiatry has forgotten but shouldn't have, and that list includes effective drugs that are no longer prescribed, diagnoses that correspond to natural disease entities, and the now abandoned tradition of treating psychiatry and neurology as a single discipline.

So, I’m totally willing to join the chorus of dubiety about hyperthermia today, except that the historian in me says, wait a minute . . . .