The Burden of Cardiac Complications in Patients with Community-Acquired Pneumonia

In a study to determine risk factors for cardiac complications among 3068 patients with CAP, Griffin et al applied a purposeful selection algorithm to a list of factors with reasonable potential to be associated with the 376 patients who actually had a cardiac complication [27]. After multivariate logistic regression analysis, hyperlipidemia, an infection with Staphlococcus aureus or Klebsiella pneumoniae, and the PSI were found to be statistically significant. In contrast, statin therapy was associated with a lower risk of an event.

In 2014, a validated score similar to the PSI and using the same database was derived to predict short-term risk for cardiac events in hospitalized patients with CAP [28]. It attributes points for age, 3 preexisting conditions, 2 vital signs and 7 radiological and laboratory values, with a point scoring system that defines 4 risk stratification classes. In the derivation cohort, the incidence of cardiac complications across the risk classes increased linearly (3%, 18%, 35%, and 72%, respectively). The score was validated in the original publication with a separate database but has not been evaluated since. The score outperformed the PSI score in predicting cardiac complications in the validation cohort (proportion of patients correctly reclassified by the new score, 44%). Potentially, the rule could help identify high-risk patients upon admission and could assist clinicians in their decision making.

Strategies to Prevent Cardiac Complications During CAP

It is now well established that there is a heavy burden of long-lasting cardiac complications among patients with CAP; therefore, preventing CAP should be a priority. This can be accomplished by counseling patients to refrain from alcohol and smoking and by administering influenza ( Table 2 ) and pneumococcal vaccines ( Figure 2 ). Since the 7-valent protein-polysaccharide conjugate pneumococcal vaccine (PCV-7) was released for children in 2000, there have been fewer hospitalizations in the United States [27] and improved outcomes globally; for instance, fewer hospitalizations among children < 14 years of age in Uruguay [29], and decreased invasive pneumococcal disease among children < 5 years of age in Taiwan [30]. Furthermore, a decrease in invasive pneumococcal disease by 18% in persons aged > 65 years in the US and Canada decreased with the introduction of PCV-7 to children. Although this showed a beneficial indirect effect (herd immunity) in unvaccinated populations [31,32], there have been no randomized controlled trials in adults demonstrating a decrease in pneumococcal pneumonia or invasive pneumococcal disease which were vaccinated with PCV-13. The Food and Drug Administration approved PCV-13 for children in 2010 and for adults in 2012. Although it included fewer serotypes, it did include serotype 6A, which has a high pathogenicity and is not in 23-valent pneumococcal polysaccharide vaccine (PPSV-23). The criteria for vaccinating adults for pneumococcal infection were recently published [33]. A study of patients with invasive pneumococcal disease, which also determined pneumococcal serotypes, included 5 patients who had CAP as well [34]. Those patients had serotypes 6A, 7C, 14, and 23F (2 patients). The patient who had serotype 14 (higher pathogenicity) died and the other 4 lived. Serotypes 14 and 23F are in both vaccines while serotype 7C is in neither. Vaccination status was not provided in the study. At this time, there is evidence to support vaccinating patients for both S. pneumoniae and influenza virus.