BACKGROUND: People with chronic obstructive pulmonary disease (COPD) are at increased risk of pneumococcal disease, especially pneumonia, as well as acute exacerbations with associated morbidity and healthcare costs.
OBJECTIVES: To determine the efficacy of injectable pneumococcal vaccination for preventing pneumonia in persons with COPD.
SEARCH METHODS: We searched the Cochrane Airways COPD Trials Register and the databases CENTRAL, MEDLINE and Embase, using prespecified terms. Searches are current to November 2016.
SELECTION CRITERIA: We included randomised controlled trials (RCT) comparing injectable pneumococcal polysaccharide vaccine (PPV) or pneumococcal conjugated vaccine (PCV) versus a control or alternative vaccine type in people with COPD.
DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. For meta-analyses, we subgrouped studies by vaccine type.
MAIN RESULTS: For this update, we added five studies (606 participants), meaning that the review now includes a total of 12 RCTs involving 2171 participants with COPD. Average age of participants was 66 years, male participants accounted for 67% and mean forced expiratory volume in one second (FEV1) was 1.2 L (five studies), 54% predicted (four studies). We assessed risks of selection, attrition and reporting bias as low, and risks of performance and detection bias as moderate.Compared with control, the vaccine group had a lower likelihood of developing community-acquired pneumonia (CAP) (odds ratio (OR) 0.62, 95% confidence interval (CI) 0.43 to 0.89; six studies, n = 1372; GRADE: moderate), but findings did not differ specifically for pneumococcal pneumonia (Peto OR 0.26, 95% CI 0.05 to 1.31; three studies, n = 1158; GRADE: low). The number needed to treat for an additional beneficial outcome (NNTB) (preventing one episode of CAP) was 21 (95% CI 15 to 74). Mortality from cardiorespiratory causes did not differ between vaccine and control groups (OR 1.07, 95% CI 0.69 to 1.66; three studies, n = 888; GRADE: moderate), nor did all-cause mortality differ (OR 1.00, 95% CI 0.72 to 1.40; five studies, n = 1053; GRADE: moderate). The likelihood of hospital admission for any cause, or for cardiorespiratory causes, did not differ between vaccine and control groups. Vaccination significantly reduced the likelihood of a COPD exacerbation (OR 0.60, 95% CI 0.39 to 0.93; four studies, n = 446; GRADE: moderate). The NNTB to prevent a patient from experiencing an acute exacerbation was 8 (95% CI 5 to 58). Only one study (n = 181) compared the efficacy of different vaccine types - 23-valent PPV versus 7-valent PCV - and reported no differences for CAP, all-cause mortality, hospital admission or likelihood of a COPD exacerbation, but investigators described a greater likelihood of some mild adverse effects of vaccination with PPV-23.
AUTHORS' CONCLUSIONS: Injectable polyvalent pneumococcal vaccination provides significant protection against community-acquired pneumonia, although no evidence indicates that vaccination reduced the risk of confirmed pneumococcal pneumonia, which was a relatively rare event. Vaccination reduced the likelihood of a COPD exacerbation, and moderate-quality evidence suggests the benefits of pneumococcal vaccination in people with COPD. Evidence was insufficient for comparison of different pneumococcal vaccine types.
The review highlights the value of the pneumococcal vaccine among patients with COPD to reduce the risk for a COPD exacerbation, but not much else. The limited efficacy in reducing patient-oriented outcomes is important, but given American health care`s focus on vaccination rates as a measure of quality, I`m afraid this article will not change physicians` behaviors around vaccination counseling or vaccine ordering.
This analysis confirms the utility of vaccination against pneumococcus in patients with COPD. It suggests that this should be a standard of care.
This Cochrane meta-analysis shows that the pneumococcal vaccine reduces pneumonia and exacerbations, but not mortality, in COPD patients. It updates a previous review, which also found the effect in pneumonia, but the finding regarding exacerbations is new and important. This removes some uncertainty that had been underlying guideline recommendations regarding pneumococcal vaccination in COPD. While the use of the PPV-23 vaccine in COPD is well-established in practice, it is disappointing that this review did not look at the evidence for the PCV-13 vaccine (alone or in combination with PPV-23), which North American guidelines have recently recommended as well in COPD.