Do statistics have a use by date?

The website of Mental Health America (“the nation’s leading community-based non-profit dedicated to helping all Americans achieve wellness by living mentally healthier lives”) has a page on electroconvulsive therapy (ECT).

“Today, ECT is administered to an estimated 100,000 people a year, primarily in general hospital psychiatric units and in psychiatric hospitals.”

Mental Health America is by no means alone in using that figure of 100,000. “Today, as many as 100,000 people in the U.S. receive ECT each year to treat these mental illnesses” says Windmoor Healthcare. “Today, an estimated 100,000 people across the U.S. choose to be treated with ECT each year” says UTHealth (the University of Texas Medical School). And so on. Today, they say, not yesterday or a few years ago or 25 years ago, but today an estimated 100,000 people are being given ECT in the United States. But who came up with the estimate and, more importantly, when? Here is a rare example of the figure of 100,000 being more or less correctly quoted (on the UpToDate website): “A practice survey from 1988-89 estimated that at least 100,000 patients in the United States received ECT annually” (although I don’t think the original survey contained that “at least”).

That statistic may still be valid for 1988-89, unless someone comes up with a major objection to the methodology of the survey. But it is an estimate of how frequently ECT was used then – over 25 years ago – and not today. In fact it was probably out of date by the time it was published in 1995. The amount of ECT used can change significantly over a period of 25 years. In England, for example, its use has declined by over two-thirds since 1988-89.

Are there any more recent estimates of how frequently ECT is used in the United States? One recently published article (Indicators for electroconvulsive therapy among patients hospitalized for depression by M.A.K. Suri et al. in the Psychiatric Annals) looked at data from the National Inpatient Sample (NIS) from 2009 to 2010 and came up with a figure of 20,251 patients hospitalized with a primary diagnosis of major depression undergoing ECT. That figure of 20,251 is not of course the total number of people undergoing ECT in the United States today. It was, for example, already five years out of date by the time it is published. It refers only to people being treated for depression, while a minority of ECT patients are being treated for schizophrenia and other disorders. I don’t know if there are places in the United States that use ECT and are not part of the NIS, or indeed how reliable the NIS statistics are, or whether, for example, they include ECT given on an out-patient basis. But at least the statistic could form a starting point for an estimate of the numbers of people undergoing ECT. And it is, incidentally, much more in line with statistics from Texas, one of the few states to collect and publish statistics on ECT, than the 100,000 figure.

The authors of the recent study found that women who were admitted to hospital with depression were more likely than men to be prescribed ECT. Surveys of ECT use in Western countries have consistently found that women account for the majority of patients, usually between 60 and 70 per cent. Psychiatrists explain this by saying that women are more likely to become depressed than men. But explaining why, once admitted to hospital, women are more likely than men to be given ECT is more difficult.

The recent study found that ECT patients had an average age of 41 years (compared to 57 for those who did not receive ECT). This is a lot lower than the average age of ECT patients in, for example, the UK. It is also in line with the Texas statistics, which show patients getting younger over recent years, and with a 2013 article that found that the recent decline in ECT use was “driven by dramatic declines among elderly persons” (Declining use of electroconvulsive therapy in United States general hospitals by B.G. Case et al. Biological Psychiatry 2013 Jan 15;73(2):119-26). That makes it even more bizarre for Mental Health in America, one of the websites I quoted at the beginning of this post, to say: “During the last decade, the “typical” ECT patient has changed from low-income males under 40, to middle-income women over 65.” That may perhaps have had a grain of truth to it some 40 or 50 years ago, but not today.

This entry was posted in ECT worldwide, Gender ECT. Bookmark the permalink.

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