This news release from Case Western Reserve University sets out to describe a relatively small study designed to further previous evidence for an observed link between gum disease and prostatitis (inflammation of the prostate). The study focuses on the likely common denominator of a body-wide biological process that releases inflammatory cytokines into blood and tissue, along with other possibilities; and on the clear possibility that non-surgical dental treatment will help. The study report in the journal Dentistry goes to some lengths to caution readers about the very shaky nature of this evidence and the fact that the study was not designed to establish a cause-and-effect relationship between periodontitis (the fancy name for inflammatory gum disease) and high PSA levels in the blood of men with prostatitis symptoms. The study authors also lay out several caveats and limitations of their study, including the small number of participants and lack of a control group. Alas, the release fails to exercise that same wise caution. It misleadingly refers to PSA reductions that were not statistically significant, and states flatly that “Treating gum disease reduced symptoms of prostate inflammation.” This overstates the value of the evidence presented in the study.
Both periodontal disease and prostate disease (inflammation, tissue and tooth loss, and cancer) are widespread and have serious health consequences. Indeed, as the release and study point out, the suspected inflammatory process involved in both has also been linked to some forms of heart disease and autoimmune forms of arthritis. As a result, promoting dental care for gum disease as a means of reducing PSA levels and prostatitis (potential precursor signs of prostate cancer) poses a tantalizing means of controlling real health problems. Promoting evidence that supports the value of dental therapy in this context, however, should be accompanied by caution about the well-known debates over the meaning of high or low PSA levels (especially in younger men and with only a single PSA test); and caution as well about the limitations of self-reported symptoms of prostatitis in a study with no control group. The authors of the study provide important context on these issues; we wish the news release had followed that lead.
The release and the study both suggest that treating periodontal disease might be a “required approach” to reducing prostate inflammation and possibly prostate cancer.” So the release probably should have said something about the social and financial costs of untreated gum disease and prostatitis, and the costs of providing dental care to what is likely a substantial percentage of the population. It’s likely that if further studies do in fact demonstrate the value of dental treatment that money might be saved in terms of downstream treatment of prostatitis, prostate cancer, and dental disability. Dental care is not cheap in the United States, and insurance coverage, even where it exists, usually pays for only a fraction of the care.
Also, not mentioned anywhere is that PSA testing as a routine cancer screen is not recommended anymore. Unnecessary testing is costly.
The journal article that’s the basis for the release provided quantitative data about the percentage of reduction of gum disease and PSA levels, as well as reports of reduced symptoms.
The release, however, sticks to generalities, noting “reduced symptoms,” quoting the principal investigator about “improved” symptoms of prostatitis in those treated for gum diseases, and noting “significant improvement” for those with the “highest level” of inflammation. The release includes no quantification.
In addition, the release mentions that PSA levels dropped in 21 of the 27 men who received periodontal treatment, but this is a misleading claim. A closer look at the study data shows that the reductions in PSA levels were not statistically significant. And in the participants who had low levels of inflammation at baseline, the mean PSA level actually went up.
The release clearly assumes readers will understand there is potential harm from untreated gum or prostate disease and that is probably reasonable. It might have described the risks and limitations of repeated PSA screening and biopsies (which can lead to false-positive results and unecessary treatment), but we don’t think that was an essential part of this analysis. Nonsurgical treatment of periodontal disease has a low potential for harm, something the release could have mentioned. The release does point out the risk to heart patients and pregnant women of untreated periodontal disease.
As noted above, the study report is quite self-critical with respect to the limitations of its findings, which include the small size of the study and the lack of a control group, among other things. But we’d note that the study’s title — “Periodontal Treatment Improves Prostate Symptoms and Lowers Serum PSA in Men with High PSA and Chronic Periodontitisis” — does not reflect that uncertainty, so the study author themselves should certainly share some responsibility for the fact that their findings have been miscommunicated.
We’d add that not knowing how gingivitis was treated (no information about this is included in either the study or release) hinders any assessment of the findings. The treatments presumably included such things as root planing, tooth scaling, flossing and the use of mouth rinses. But if the treatment involved antibiotics, for example, this could have affected prostatitis symptoms and PSA levels. The release includes none of this context.
The release actually offers no incidence or prevalence data at all, and as a consequence, makes no overstatements about either gum disease or inflammatory disorders that are linked to it.
The release doesn’t discuss funding, but the paper says that the study was sponsored by the authors’ departments at the university. There’s really no harm in leaving this information out, so we’ll rule this Satisfactory.
How is prostatitis currently treated? How do the results reported here compare with those treatments? The release doesn’t say.
The release suggests that dental care should probably be a routine part of efforts to control prostate disease, but doesn’t address the issue of financial barriers to such care, particularly for the uninsured. But we’re inclined to overlook this because of the nature of the study: it’s a pilot; it was designed to add to evidence for a relationship between gum and prostate disease via an inflammatory process; and the dental care involved is widely available and commonly provided to those who have regular dental care.
The release does a good job of noting that this is not the first time a link has been suggested between gum and prostate disease and refers to previous studies by the research group.
The study that’s the basis for this news release clearly states that no cause and effect relationship can be inferred from this very limited data. And yet the news release leads with a statement that “Treating gum disease reduced symptoms of prostate inflammation.” That’s simply not justifiable.