In persons with a diagnosis of chronic obstructive pulmonary disease (COPD), the trivalent seasonal influenza vaccine (TIV) and the 23-valent pneumococcal polysaccharide vaccine (PPSV23) can reduce the risk of hospitalization for acute exacerbations of COPD (AECOPD), pneumonia, and related illnesses, according to study findings published recently in the journal Respirology.
The study authors found similar results whether the vaccines were administered separately or together.
As context for their research, investigators from the National Immunization Program, Chinese Center for Disease Control and Prevention, Beijing, China, point to the gap in research looking at the efficacy of the 2 vaccines, alone or combined, against poor outcomes in COPD.
Using a self-controlled, before-and-after design, the researchers first recruited patients from hospitals in Tangshan City of Hebei Province in China during September 2018. Eligibility required a diagnosis of COPD and a postbronchodilator forced expiratory volume in 1 second-to-forced vital capacity (FEV1/FVC) ratio of <0.70.
Participants were self-selected into 3 groups based on vaccinations between October 31, 2019, and November 15, 2019: TIV, PPSV23, or both vaccines.
The final cohort numbered 474 patients who had received at least 1 vaccine. The median age of the patients was 66 years and 285 (60.13%) were aged ≥65 years. The majority (78.48%) were men, and investigators noted that 73.8% were coal miners or former coal miners. COPD was diagnosed most commonly as moderate or severe.
The vaccine groups were as follows: TIV, n=109; PPSV23, n=69; both, n=296.
During the 2-year follow up period, there were 427 outcome-related events. Of those AECOPD, pneumonia, and hospitalizations accounted for 30.91%; AECOPD and pneumonia, 8.43%; AECOPD and hospitalization, 36.77%; pneumonia and hospitalization, 3.04%; AECOPD, 19.20%; and pneumonia, 1.64%.
Number of AECOPD, pneumonia, and related hospitalization outcomes before and after vaccination for each group were, respectively:
Decrease in incidence density for AECOPD, pneumonia, and related hospitalization for each group was, respectively
The largest decrease in incidence density was seen for AECOPD. In addition, incidence densities were greater for older participants (aged ≥65 years) vs younger and were reported to be lower among women.
Vaccine efficacy. After multivariable adjustment for age, gender, occupation, COPD severity, smoking status, and underlying disease, the effectiveness of each vaccine and of the combination for preventing AECOPD, pneumonia, and related hospitalization was, respectively:
TIV: 70% (95% CI, 49%-82%), 59% (95% CI, 11%-81%), and 58% (95% CI, 26%-76%)
PPSV23: 54% (95% CI, 26%-71%), 53% (95% CI, 8%-76%), and 46% (95% CI, 8%-69%)
TIV + PPSV23: 72% (95% CI, 62%-79%), 73% (95% CI, 58%-83%), and 69% (95% CI, 57%-77%)
The authors report, also, that vaccine effectiveness was found higher for all 3 variables outside of the nonpharmaceutical intervention period of the COVID-19 pandemic.
They conclude that TIV and PPSV23 vaccines effectively reduced the risk of AECOPD, pneumonia, and related hospitalizations, with the greatest impact in reducing AECOPD.
“Considering consistency of our results with similar studies, we infer that the effectiveness of both vaccines together is superior to effectiveness of TIV alone and that TIV is more effective than PPSV23 alone,” the authors wrote.
They also note several study limitations. Group allocation was by self-selection, which could lead to bias in group composition, limiting the ability to generalize the findings. In addition, they speculate that vaccine effectiveness may have been influenced by nonpharmaceutical intervention due to the COVID-19 pandemic (eg, masking, social distancing).
Reference: Li Y, Zhang P, An Z, et al. Effectiveness of influenza and pneumococcal vaccines on chronic obstructive pulmonary disease exacerbations. Respirol. Published online June 15, 2022. doi:10.1111/resp.14309