By Carol A. Kemper, MD, FACP

Clinical Associate Professor of Medicine, Stanford University, Division of Infectious Diseases, Santa Clara Valley Medical Center

Dr. Kemper reports no financial relationships relevant to this field of study.

Risk Behavior and Toxoplasma

SOURCE: Johnson SK, Fitza MA, Lerner DA, et al. Risky business: Linking Toxoplasma gondii infection and entrepreneurship behaviors across individuals and countries. Proc Biol Sci 2018;285(1883).

Recent studies purport various links between the human biome and latent infections. These range from viruses to parasites, to everything from overall human health and well-being, academic performance, atopy and asthma, to host immunity and even to attractiveness to the opposite sex.

The authors of this study examined the relationship between latent infection with Toxoplasma gondii and an interest in business and other entrepreneurial behaviors. Other studies have suggested a negative correlation between the prevalence of T. gondii infection and avoidance risk behavior — meaning that people who generally are risk takers are more likely to have serologic evidence of latent T. gondii infection. Why this may be the case is not at all clear. Is this, in fact, some variant of the tall height/large feet “causality,” or is there something to the emotional and psychological nature of people who are more likely to take risks and, therefore, are more willing to start a business along with a risk of parasitic infection? Or does latent infection with certain parasitic infections influence behavior through hormonal or neurological changes?

The researchers performed two studies: The first examined 1,495 students at a large university within the United States, comparing T. gondii IgG antibodies (detected via indirect competition saliva-based immunoenzyme assay [ELISA]) and their major areas of study (i.e., business-oriented majors vs. non-business majors), including such areas of study as marketing, finance, and accounting. Of these students, 22% tested positive for T. gondii IgG antibodies. While controlling for sex and grade point average, the researchers found that positive antibody status significantly correlated with majoring in business-related fields (P < 0.005). Among 1,293 students with either positive or negative results (excluding those with indeterminate results), 31% of business majors compared with 22% of non-business majors tested positive for T. gondii IgG antibody. Further, those students with interest in establishing their own business or demonstrating management and entrepreneurial tendencies were 1.7 times more likely to have T. gondii antibodies compared to those in other business areas.

A second study was conducted with 197 individuals attending entrepreneurial events who offered to provide a saliva sample and answer a brief questionnaire. Once again, the presence of T. gondii antibody positively predicted an interest in business and entrepreneurship. Antibody-positive individuals were 1.8 times more likely to have started a business successfully than those who tested negative.

The authors admitted that any relationship between behavior and parasitic infection probably is complex and influenced by myriad unknown variables. Could this be as simple as people who love business also travel abroad more frequently, have a tendency to eat more undercooked red meat, or love to hunt elk or deer and make their own sausage? A direct effect of parasitic infection seems less likely than a behavioral link.

Embolic Risk and Vegetation Size

SOURCE: Mohananey D, Mohadjer A, Pettersson G, et al. Association of vegetation size with embolic risk in patients with infective endocarditis. A systematic review and meta-analysis. JAMA Intern Med 2018;178:502-510.

In studies of infective endocarditis (IE), researchers have observed an increased risk of embolic events with echocardiographic evidence of larger vegetations, although it is recognized that certain bacteria have a propensity for early and more frequent embolism. As a result, consideration of surgical options, in addition to medical therapy, has been recommended for aortic or mitral valve vegetations greater than 10 mm in size.

To better assess the effect of vegetation size on embolic risk, Mohananey et al performed a meta-analysis involving available observational studies of randomized clinical trials of endocarditis and embolic risk. Only those studies based on two-dimensional transthoracic or transesophageal echocardiography in which vegetation size was measured and clearly specified and an odds ratio (OR) of embolic risk was determined were included in the analysis. Studies of IE involving prosthetic valves or cardiac devices were excluded unless they also included cases of IE involving native valves.

A total of 21 unique studies published from 1983 to 2016 were identified, encompassing a total of 6,646 patients with IE, for which vegetation size was clearly specified in 5,116. Using Mantel-Haenszel statistical testing (which gives weight to the individual ORs based on the weight of the study), the overall OR of an embolic event for those with valve vegetation size 10 mm or greater was 2.28 compared to those with vegetation size 10 mm or less (P < 0.001; range of OR varied from 0.19-15.22). In addition, investigators observed an increase in all-cause mortality for those with vegetation size greater than 10 mm compared to those with smaller vegetations (OR 1.63; P = 0.009).

Multiple subgroup analyses were performed. When studies performed from 1983 to 1999 were pooled, an increased risk of embolic events with vegetation size greater than 10 mm was observed but did not meet statistical significance. However, in those studies published from 2000 to 2016, a statistically significant increased risk of an embolic event was observed for larger vegetations. The authors suggested this may be the result of improvements in echocardiography, leading to more accurate identification and measurement of smaller vegetations. They also examined studies based on the use of Duke or modified Duke criteria compared to those that did not, and found similar results. Further, using various vegetation size cut-offs from 5 mm to 15 mm, the authors found the odds of an embolic event using a cut-off of 5 mm was similar to that observed using a cut-off of 10 mm.

While it is recognized that certain bacterial pathogens, such as Staphylococcus aureus and the HACEK organisms, are more likely to cause “more friable” vegetations with an increased risk of embolism, there were insufficient microbiologic data to include in the analysis. Their analysis of the percentage of S. aureus infection among the studies analyzed did not show a clear trend. In addition, while the authors attempted to focus their analysis on native valve IE, 14 of the 21 studies in the analysis included some number of prosthetic valves, ranging from 2% to 30% of reported cases. A subgroup analysis suggested these cases did not significantly affect the overall results.

Recertification: Is There a Better Way?

SOURCES: Gray B, Vandergrift J, Landon B, et al. Associations between American Board of Internal Medicine maintenance of certification status and performance on a set of healthcare effectiveness data and information set (HEDIS) process measures. Ann Intern Med 2018;169:97-105.

Goldman L. Maintenance of certification: Glass not entirely empty? Ann Intern Med 2018;169:124-125.

The American Board of Internal Medicine (ABIM) has taken heat lately for its stringent certification requirements that go well beyond what is required for state licensure or hospital privileges as well they should. In short, there is no good evidence that Maintenance of Certification (MOC) status and the requirements of a rigorous closed-book examination independently correlate with better physician performance. MOC is time-consuming, detracts from and disrupts usual clinical practice, soaks up valuable remaining family time, and imposes a burden on colleagues and it’s expensive. Fulfilling MOC requirements for a general internist is estimated to cost $17,000 per physician every 10 years, at a time when many physicians are shuttering their practices because of lower reimbursements, increasing regulation, and increased costs. And who benefits from this expense? The very organization that requires it and there are no alternative certifying options. Simply signing up for the ABIM MOC program costs $2,600, which does not include the cost to attain the actual required MOC credits. Further, the ABIM seems to have a lock on what satisfies MOC credit. I was stunned to learn that only a fraction of the CME credit earned attending IDWeek 2016 qualified for MOC.

The authors of a recent Annals article attempted to confirm whether MOC status correlates with any meaningful clinical measure of performance as a general internist. The investigators examined older internists who initially certified in 1991 and who provided care to Medicare patients between 2005 and 2012. These were grouped by MOC status and how often they met current standards for hemoglobin A1c testing, annual lipid-cholesterol screening, and three other diabetes standards of care. After multiple adjustments to their model, between those physicians who maintained certification and those who did not, the authors successfully confirmed that MOC status correlated with small but measurable differences in these five Healthcare Effectiveness Data and Information Set (HEDIS) standards. By way of example, MOC physicians more frequently provided annual lipid-cholesterol measurements than non-MOC physicians (83.1% vs. 80.5%; confidence interval [CI], 0.6-4.1; P = 0.008). Biennial mammography also was performed more often in patients of MOC physicians than of non-MOC physicians (79.4% vs. 77.4%; P = 0.032). Comparing MOC vs. non-MOC physician results, hemoglobin A1c testing was obtained in 58.4% vs. 54.4% of their patients.

Requirements for accreditation should not be based on such meager differences in outcomes. As the authors of an accompanying editorial pointed out, these small differences could be explained by a myriad of cofactors. Any small confounder with a relative risk of 1.2 could easily explain away these differences anything from the type of computer system to which physicians have access to the patient group they serve. Our computer system includes best practice alerts for hemoglobin A1c; I don’t even have to think about it, I just click the button. Does this make me a better physician?

What was not clearly explained in this article was that rates below 50% for hemoglobin A1c testing warrant a grade of F according to HEDIS standards, suggesting that MOC certification might raise up some physicians from an F to an F+ or D-. The authors of an accompanying editorial suggested that any certification that lets you, as the consumer, know that a physician has a slightly better F than his colleague down the road is not really meaningful.

Since the ABIM is holding physicians accountable, let’s make the ABIM accountable. If there are requirements, let’s make them meaningful and cost-effective.

Now that a year has passed since I was forced to recertify in infectious disease (and I am not spitting as many nails), I will share my own experience. Shortly before my 59th birthday, I was informed by my employer that I was “out of compliance” with board certification. I initially certified in infectious disease in 1991, just months after the cut-off for non-requirement, but was under the misapprehension that further recertification was not required. I recertified voluntarily in 2005 because I thought it would be fun and interesting. It turns out my new employer, who had purchased our group, apparently required current subspecialty certification. Worse, I was informed that if I did not sign up for MOC immediately and pass the exam, I would lose my job. (I could continue to work per diem with no benefits or healthcare.) During my 27 years of experience, I have written this column for 22 of those, have maintained state licensure and CME credit, and I am a fellow of the American College of Physicians and the Infectious Diseases Society of America (IDSA).

I cleared my schedule, spent every weekend from February to April studying, took two weeks of vacation and I memorized. I went over and over material, I completed several of the IDSA modules (which I thought were good), I tried to review old textbooks (which were out of date), and, finally, at a colleague’s suggestion, I signed up for an online ID review course (which cost $1,100). And I memorized. The sheer amount of material you have to remember is daunting material that I usually know where to reach for when needed.

The examination was brutal: 10 hours locked in a room, walled up in a cubbyhole; allowed only three breaks totaling no more than 1.5 hours (not even a bathroom break). The questions were dizzyingly difficult and tricky. I barely finished one of the sections in time. Of course, throughout, I knew if I didn’t pass, I was going to lose my job. I admit, I was traumatized for weeks. Of course, I passed. That’s not the point.

Did I gain anything from the experience, other than keeping my job? In all honesty, I enjoyed indulging in the long hours of study. I loved the slide shows and images of diseases, bugs, and worms. I loved listening to Dr. John Bennett (such a treat!) and other experts speak. I admit, I filled in some gaps in my knowledge, especially about newer antibiotics and HIV medications. However, I could have accomplished the same result by completing a one-week board review course and an open book exam, with far less anxiety, time, and expense.