Ineffectiveness of Pneumococcal Vaccination in Cardiovascular Prevention: The CAPAMIS Study

Study Questions:

What is the effectiveness of pneumococcal polysaccharide vaccine (PPV23) against community-acquired pneumonia (CAP), acute myocardial infarction (AMI), and stroke among the general population 60 years or older?

Methods:

This was a closed, population-based prospective cohort study including 27,204 individuals 60 years or older assigned to nine primary care centers (PCCs) inTarragona, Spain, who were prospectively followed from December 2008 until November 2011. The PCC’s electronic clinical record system was used to classify cohort members by their pneumococcal vaccination status, as well as to identify baseline characteristics and underlying conditions of the cohort at study start. Primary outcomes were hospitalization for CAP, AMI, and ischemic stroke. Cox regression models were used to assess the association between having received PPV23 and the time to the first outcome.

Results:

In the primary analyses, PPV23 vaccination did not substantially alter the risk of CAP (hazard ratio [HR], 0.94; 95% confidence interval [CI], 0.80-1.12; p = 0.51), AMI (HR, 1.01; 95% CI, 0.82-1.25; p = 0.92), or ischemic stroke (HR, 1.03; 95% CI, 0.83-1.28; p = 0.81). After propensity and multivariate adjustments, PPV23 vaccination remained unassociated with the outcomes studied.

Conclusions:

The authors concluded that PPV23 does not provide any clinically relevant benefit against overall CAP, AMI, or stroke among the general population older than 60 years.

Perspective:

Overall, the study data do not support a cardiovascular protective role of PPV23, and refute prior data reporting a protective effect. The study findings show an increased short-term risk of acute thrombotic events among patients with CAP (2.8% and 0.7% of them developed AMI or ischemic stroke within 30 days after a CAP diagnosis, respectively), but vaccination did not reduce these risks. More effective antipneumococcal vaccination strategies using conjugated and/or protein-based pneumococcal vaccines for adults may be indicated.

Keywords: Risk, Stroke, Myocardial Infarction, Pneumonia, Vascular Diseases, Community-Acquired Infections, Pneumococcal Vaccines, Proportional Hazards Models, Spain, Confidence Intervals, Primary Health Care


< Back to Listings