This news release focuses on a recent article published in the journal PLOS ONE, reporting that the use of the corticosteroid dexamethasone and avoiding “deep” or “profound” anesthesia during surgery can reduce the incidence of post-operative cognitive dysfunction (POCD) in older patients. However, the release does not give readers any context for understanding the reduced incidence of cognitive dysfunction after anesthesia, and does not discuss costs or potential harms associated with dexamethasone use.
POCD is not uncommon. A 2014 literature survey paper found that 41.4 percent of patients age 60 or older who had major surgery (other than cardiac surgery) were exhibiting symptoms of POCD when discharged from the hospital. Three months later, 12.7 percent of those older adults were still experiencing POCD. But older adults aren’t the only ones affected; more than 30 percent of adults under the age of 60 also experience POCD after major surgeries. And in addition to being fairly common, POCD can have a significant impact on a patient’s health, quality of life and recovery. A major issue for older adults who have cognitive issues after surgery is their ability to care for themselves. All of these factors make POCD prevention a subject of public interest. However, as with any health-related research news, the costs, benefits and risks need to be clearly outlined. And that’s missing here.
The release doesn’t discuss cost at all, which is somewhat surprising given that dexamethasone has been on the market for many years with various clinical applications. It’s not that dexamethasone is especially expensive (it isn’t — though the cost isn’t necessarily negligible), but that cost needs to be addressed. Readers are simply given no information about cost.
The release explains that the overall pool of 140 patients was split into four groups: Group One did not receive dexamethasone and was under “deep” anesthesia; Group Two did not receive dexamethasone and was under “superficial” anesthesia; Group Three received dexamethasone before surgery and was under “deep” anesthesia; Group Four received dexamethasone before surgery and was under “superficial” anesthesia. Got all that? The release tells readers that patients in Group Four had a 15.3 percent incidence rate of POCD immediately after surgery, and that none of the Group Four patients had POCD six months after surgery. We’re glad that the release provides a specific, quantified benefit. However, the release does not give readers the information they need to understand what that number means. For example, what was the POCD incidence rate for any of the other groups immediately after surgery? What was the incidence rate for other groups after six months? What does the literature have to say about how common POCD is for patients in this age range and receiving this type of surgery? Without any of that information, it is impossible for readers to determine whether a 15.3 percent incidence rate of POCD is good or bad.
While the release refers in general to the risks inherent with both deep and superficial anesthesia, it does not mention any of the potential side effects associated with its recommended intervention, dexamethasone. And there is no shortage of information on dexamethasone available. According to the U.S. National Library of Medicine’s Medline Plus page on dexamethasone, the drug’s side effects range from vomiting to insomnia to depression. The page indicates that dexamethasone may also interact with a variety of other widely-used drugs. In addition, giving patients steroids, of which dexamethasone is one, increases the risk of infection or worsening severity of existing infections. We don’t expect a release to provide an exhaustive list of side effects, but acknowledging that there are known risks associated with the drug is important.
The release explains that “The researchers evaluated 140 patients aged between 60 and 87 who underwent surgery under propofol-induced general anesthesia at the Central Institute of Hospital das Clínicas, FM-USP’s teaching hospital, in most cases for removal of gallstones.” The release further explains that patients were divided into four groups (as we described above, under the Benefits section), and defines what constitutes “deep” anesthesia and “superficial” anesthesia. Those are all good things. However, the release would have been much stronger if it had done three things. First, it should have made clear that all of the surgeries were non-cardiac, non-neurological surgeries. Given how common these surgeries — particularly cardiac ones — are for older patients, this is an important point. Second, the release should have made it more clear that the benefits observed were based on one group (i.e., Group Four) of only 32 patients. This is a preliminary finding, and that needs to be stressed. Third, while the release tells readers that the anesthetic used was propofol, it doesn’t tell readers how common or widely-used this drug is as a surgical anesthetic. That would be valuable context.
The release does not engage in disease mongering.
The release does not explicitly note who funded the study. However, the study does not appear to have received any external funding. According to the ClinicalTrials.gov page for the study, the work was sponsored primarily by the University of São Paulo and Duke University (where the authors work), with additional support from the Fundação de Amparo à Pesquisa do Estado de São Paulo (or São Paulo Research Foundation), which is public. It’s not unusual for universities to avoid mentioning funding for projects that they funded themselves. But it would have been a stronger release if it didn’t leave readers wondering who paid for the work.
Frankly, there’s not a lot of research out there on steps to pro-actively reduce rates of cognitive dysfunction after anesthesia, and we’re not aware of alternative interventions designed to do so.
It’s clear from the release that the relevant tools involved in this particular intervention — the use of dexamethasone and avoidance of “deep” anesthesia — are currently available. However, as noted above, this is a relatively small study, and we suspect that more research would be needed before this approach was considered for widespread clinical practice. Since we already dinged it for that point earlier, we’ll give it a satisfactory here.
It’s clear from the release that this is a new (and, ergo, novel) approach addressing a well-established problem.
The release uses responsible language to discuss the findings, although it could have been more clear about the preliminary nature of the work. A larger study is almost certainly called for on this intervention.
We do have some concerns over the use of the acronym “POCD” to describe cognitive dysfunction following anesthesia. It appears to be a coined medical term that few clinicians use.