Publications of the Week, August 28

2017-08-28

Preventing CDI with timely probiotic administration

Shen NT, Maw A, Tmanova LL, et al. Timely Use of Probiotics in Hospitalized Adults Prevents Clostridium difficile Infection: A Systematic Review With Meta-Regression Analysis. Gastroenterology. 2017 Jun;152(8):1889-1900.e9. doi: 10.1053/j.gastro.2017.02.003. Epub 2017 Feb 10. Review. PubMed PMID: 28192108.

Among hospitalized patients treated with antibiotics, use of probiotics reduces the risk of Clostridium difficile infection (CDI) by about half. The effect may depend on timing of probiotic use (sooner rather than later).

In this meta-analysis the authors included 19 studies enrolling over 6200 patients. The risk of CDI in the control group ranged from 0% to 40% with a median of about 4%, and in the probiotic group, from 0% to 11%. The use of probiotics resulted in the risk of CDI decreased by more than a half, from about 3.9% to about 1.6% (relative risk [RR], 0.42; 95% confidence interval [CI], 0.30-0.57). In the studies where probiotics were given within 2 days of antibiotics use, the reduction in risk appeared larger (RR, 0.32; 95% CI, 0.22-0.48). Delayed probiotic administration seemed less effective (RR, 0.70; 95% CI, 0.40-1.23).

The authors were not able to detect effects of intervention dependent on unique probiotic formulations, delivery method (liquid, capsule), or doses. They point, however, to low-confidence positive trends associated with the use of Lactobacillus alone, in combination with Streptococcus, or in combination with both Streptococcus and Bifidobacterium.

ICDs, mortality reduction, and CAD

Shun-Shin MJ, Zheng SL, Cole GD, Howard JP, Whinnett ZI, Francis DP. Implantable cardioverter defibrillators for primary prevention of death in left ventricular dysfunction with and without ischaemic heart disease: a meta-analysis of 8567 patients in the 11 trials. Eur Heart J. 2017 Jun 7;38(22):1738-1746. doi: 10.1093/eurheartj/ehx028. PubMed PMID: 28329280; PubMed Central PMCID: PMC5461475.

Implantable cardioverter defibrillators (ICDs) reduce total mortality among patients with left ventricular dysfunction (LVD) by about a quarter irrespective of the presence or absence of coronary artery disease (CAD).

This meta-analysis of 11 randomized trials addressed the efficacy of ICDs in patients with LVD. Most primary studies included patients with left ventricular ejection fraction of 35% or less and with a New York Heart Association class III or class II; 5 studies included patients with class I. Among the included patients, over 3100 had no evidence of CAD, whereas in over 5400 CAD was present.

The mean age of patients across trials was 63 years. Among patients with LVD but without CAD, the annualized mortality rate was 5.4%. The implantation of ICDs resulted in lowering of total mortality by about a quarter (hazard ratio [HR], 0.76; confidence interval [CI], 0.64-0.90), which translates into slightly over 1% of the absolute difference in mortality per year. The relative results among people with underlying CAD who received ICDs during a procedure separate from revascularization bypass (excluding one study where both procedures were performed) were very similar (HR, 0.76; 95% CI, 0.60-0.96) with a higher baseline mortality rate (11.3%) and therefore likely larger absolute benefit. The inclusion of the study where the ICD was inserted at the time of bypass surgery was associated with a loss of overall statistical significance of the meta-analysis (relative risk, 0.81; 95% CI, 0.65-1.03).

Lectures in medical education: a thing of the past?

Schwartzstein RM, Roberts DH. Saying Goodbye to Lectures in Medical School - Paradigm Shift or Passing Fad? N Engl J Med. 2017 Aug 17;377(7):605-607. doi: 10.1056/NEJMp1706474. PubMed PMID: 28813217.

In this perspective/opinion paper, the authors point to the phenomenon of a decreasing use of lectures in medical education and explore some of the known and unknown reasons and effects of such a trend.

Some areas considered by the authors include the rise of problem-based learning, self-directed learning, team-based learning, easy access to factual information at the time of its volume increasing beyond human memory capacity, and need for lifelong learning and continuing professional development. The authors point out the potential difference between what is covered in a lecture and what is taught by the lecturer versus what is learned by the students. At the same time, they point towards a compromise: large group sessions with interactions, with questions directed to the audience and with time a for group discussions.

See also

We would love to hear from you

Comments, mistakes, suggestions?